preface - universitas brawijaya...13.00 - 13.30 invited a/prof. dann mallet investigating chlamydia...
TRANSCRIPT
The Third Basic Science International Conference - 2013 i
Preface
All praises are due to Allah, God Almighty, Who made this annual event of successful. The “3rd
Annual Basic Science International Conference (BaSIC-2013)” is an annual scientific event organized
by the Faculty of Mathematics and Natural Sciences, Brawijaya University. As a basic science conference,
it covered a wide range of topics on basic science: physics, biology, chemistry, mathematics and statistics.
In 2013, the conference took a theme of “Basic Science Advances in Energy, Health and Environment”
as those three aspects of life are hot issues.
The conference in 2013 was the continuation of the preceding conferences initiated in 2011 as the
International Conference on Basic Science (ICBS), where it was a transformation from the similar
national events the faculty had organized since 2004. What also changed in year 2013 was the use of the
ISSN for the conference proceedings book, instead of an ISBN used in previous proceedings books. The
change was based on the fact that BaSIC is an annual event, and, therefore, the use of ISSN is more
appropriate. The proceedings book was also divided into four books: Physics, Biology, Chemistry and
Mathematics, each with a different ISSN. The proceedings were also published in electronic forms that can
be accessed from BaSIC website. I am glad that for the first time both types of publication can be realized.
This event is aimed to promote scientific research activities by Indonesian scientists, especially
those of Brawijaya University, in a hope that they may interact and build up networks and collaborations
with fellow overseas counterparts who participated in the conference. This is in line with university vision
as a World Class Entrepreneurial University.
I am grateful to all the members of the program committee who contributed for the success in
framing the program. I also thank all the delegates who contributed to the success of this conference by
accepting our invitation and submitting articles for presentation in the scientific program. I am also
indebted to PT Semen Gresik and PT PLN (Persero) for their support in sponsoring this event.
I wish for all of us a grand success in our scientific life. And I do hope that the coming conferences
will pick up similar success, and even better.
Malang, April 2013
Johan Noor, Ph.D.
Conference Chairperson
The Third Basic Science International Conference - 2013 ii
Foreword by the Rector of Brawijaya University
First of all I would like to congratulate the Organizing Committee for the success in organizing this
amazing event. I believe all dedicated time and efforts will contribute to the advancement of our beloved
university.
I would like to welcome all participants, domestic and overseas, especially the distinguished invited
speakers, to Malang, to the conference. An international conference is a good means to establish and build
relationships and collaborations among participants. So, I hope this conference will facilitate all of you, the
academicians and scientists, to setup a network of mutual and beneficial collaboration. As a university with
a vision to be “A World Class Entrepreneurial University”, Brawijaya University will support all efforts to
realize that dream.
Finally, I do hope that the conference will run smoothly and nicely and is not the last one. I would
like to thank all parties who have lent their hands in making this conference happened.
Malang, April 2013
Prof. Dr. Yogi Sugito
Rector, Brawijaya University
The Third Basic Science International Conference - 2013 iii
Table of Contents
Preface .............................................................................................................................................................. i
Foreword by the Rector of Brawijaya University ........................................................................................... ii
Table of Contents ........................................................................................................................................... iii
Program Committee ......................................................................................................................................... v
Scientific Program ........................................................................................................................................ viii
Scientific Papers
Invited Papers
Cluster Dynamics by Ultra-Fast Shape Recognition Technique.................................................... I01
Nanotechnology Development Strategy for Supporting National Industry in Indonesia .............. I02
Role of Atomic Scale Computational Research in the Nanoscale Materials ................................. I03
Paeonilorin(PF) Strongly Effects Immuno System ........................................................................ I04
Investigating Chlamydia trachomatis using mathematical and computational .............................. I05
Recent Trends in Liquid Chromatography for Bioanalysis ........................................................... I06
Submitted Papers
Input-Output Decoupling Problem for Descriptor System: Transfer Function Matrix ApproachM01
A cellular automata model to investigate immune cell-tumour cell interactions in growing tumours
in two spatial dimensions ............................................................................................................. M02
On The Structural Properties of Latin Square in Max-Plus Algebra ........................................... M03
On Uniform Convergence of Trigonometric Series Under p-Supremum Bounded Variation
Condition ...................................................................................................................................... M04
Generalized Dedekind Modules ................................................................................................... M05
Application Random Utility Method for Economic Valuation on Change of Tourism Quality (Case
Study : Gedong Songo Temple & Muncul, Central Java Province) ............................................ M11
The Third Basic Science International Conference - 2013 iv
Application of Statistic Non Parametric-Friedmen Test In Taste Testing Snack ........................ M13
Exploring the Metacognitive Skills of Secondary School Students' Use During Problem Posing
...................................................................................................................................................... M15
Role of Teacher and Mathematical Concept to Build Student's Character by Using 'Everyone is
Teacher' Method ........................................................................................................................... M16
Object Representation on Geometry Learning using Augmented Reality Approach .................. M17
Higest Posterior Density for Identifying Differences in Gene Expression Microarray Experiments
...................................................................................................................................................... M18
Estimation in Measurement Error Models on Cases of Malnutrition in the Province of East Java
...................................................................................................................................................... M21
Non-Trend Fourier Series Estimator in Heteroscedastic Nonparametric Regression .................. M22
On the Confidence Band of Local Likelihood Estimates in Generalized Poisson Regression Model
...................................................................................................................................................... M23
Prediction of Hourly Rainfall using Bayesian Neural Network with Adjusting Procedure ........ M24
Vector Auto-Regressive Control Chart and Its Application in Industry ...................................... M25
Application of the Peak Over Threshold Method for Extreme Rainfalls Modeling in Malang
Regency ........................................................................................................................................ M26
Bayesian Confidence Interval for Smoothing Spline in Nonparametric Multivariable Regression
Model ........................................................................................................................................... M28
Full Conditional Distribution Investigation of Bayesian Poisson Lognormal 2-Level
Spatiotemporal for Analyzing DHF Risk ..................................................................................... M29
On the View of the Modeling Interregional Migration in East Java: Selected Models ............... M30
Generalized Linear Model for Estimating AIDS Cases in Indonesia .......................................... M31
Determining Teaching Quality of Lecturer Based on Questioner Using Multinomial Distribution &
Objective Bayesian....................................................................................................................... M33
Spatial Interpolation Comparison in Estimating A Coal Deposit in Kabupaten Hulu Sungai Utara,
South Kalimantan, Indonesia ................................................................................................... PSM14
Author List ............................................................................................................................................... AU-1
Acknowledgement .................................................................................................................................. ACK-1
The Third Basic Science International Conference - 2013 v
Program Committee Patrons
Rector, Universitas Brawijaya
Dean, Faculty of Mathematics and Natural Sciences, Universitas Brawijaya
Advisory Boards
Associate Deans 1, 2 and 3, Faculty of Mathematics and Natural Sciences, Universitas Brawijaya
Chairperson
Johan A.E. Noor, Ph.D.
Deputy-Chair
Dr. Suharjono
Secretary
Agus Naba, Ph.D.
Treasurers
Mrs. Sri Purworini
Mrs. Rustika Adiningrum
Mr. Surakhman
Secretariat & Registration
Dr. Masruroh
dr. Kusharto
Mr. Sugeng Rianto
Mr. Gancang Saroja
Conference Web
Agus Naba, Ph.D.
Publication & Proceedings
Arinto Y.P. Wardoyo, Ph.D.
Mr. Wasis
Public Relations & Sponsorship
Chomsin S. Widodo, Ph.D.
Mr. Moch. Djamil
Mrs. Firdy Yuana
Venue
Mr. Ahmad Hidayat
Dr. Ahmad Nadhir
Mr. Sunariyadi
Mr. Purnomo
Mr. Karyadi Eka Putra
Accommodation & Hospitality
Ms. Siti J. Iswarin
Mrs. Lailatin Nuriyah
The Third Basic Science International Conference - 2013 vi
Mrs. Nur Azizah
Mr. Robi A. Indrajit
Mrs. Trivira Meirany
Master of Ceremony
Himafis
Transportation, Excursion & Social Events
Djoko Santjojo, Ph.D.
Dr. Sukir Maryanto
Mr. Wahyudi
Mrs. Arnawati
Workshop, Poster & Scientific Exhibitions
Hari Arief Dharmawan, Ph.D.
Mr. Pudji Santoso
Mr. Sahri
Mr. Murti Adi Widodo
Documentation
Mauludi A. Pamungkas, Ph.D.
Mr. Susilo Purwanto
General Supports
Himafis
Scientific Program
Dr. rer.nat. M. Nurhuda
Dr. Sunaryo
Mr. Agus Prasmono
Local Scientific Committees (Reviewers & Editors)
Physics
Dr. rer.nat. Abdurrouf
Adi Susilo, Ph.D.
Mr. Unggul P. Juswono
Dr.-Ing. Setyawan P. Sakti
Biology
Dr. Moch. Sasmito Djati
Dr. Muhaimin Rifai
Dr. Catur Retnaningdyah
Chemistry
Dr. Masruri
Dr. Ahmad Sabarudin
Dr. Lukman Hakim
Mathematics
Dr. Agus Suryanto
Dr. Wuryansari M.K.
Dr. Rahma Fitriani
Dr. Solimun
The Third Basic Science International Conference - 2013 vii
International Scientific Committee and Editors
A/Prof. Lilibeth dlC. Coo, University of the Philippines, the Philippines
Prof. Dr. Gereon Elbers, FH Aachen, Germany
Prof. S.K. Lai, National Central University, Taiwan
Prof. Kwang-Ryeol Lee, Korean Institute of Science and Technology, Korea
A/Prof. Dann Mallet, Queensland University of Technology, Australia
Prof. Lidia Morawska, Queensland University of Technology, Australia
Prof.Dr. Petr Solich, Charles University, Czech Republic
Dr. Michitaka Suzuki, Nagoya University, Japan
Prof. Hideo Tsuboi, Nagoya University, Japan
Prof. Jia-Lin Wang, National Central University, Taiwan
The Third Basic Science International Conference - 2013 viii
Scientific Program
Time Day One – 16 April 2013 Day Two – 17 April 2013
07.30 – 08.00 Registration
08.00 – 08.30 Inaugural Session, Welcome Remarks and
Opening Ceremony Poster Preparation
08.30 – 09.00 Coffee Break
Poster Session (08.30-09.30)
(Majapahit Hall)
09.00 – 09.45
Invited Speaker 1
Prof. Lidia Morawska, Queensland University
of Technology, Australia
Title: “Emissions to the Air: from
Multidisciplinary Science to Applications”
Coffee Break (09.30 – 10.00)
09.45 – 10.30
Invited Speaker 2
Dr. rer. nat. M. Nurhuda, Universitas
Brawijaya
Title: “Towards Energy Security for the Poor”
Parallel Session (start at 10.00)
10.30 – 11.15
Invited Speaker 3
Prof. S.K. Lai, National Central Univ., Taiwan
Title: “Cluster Dynamics by Ultra-Fast Shape
Recognition Technique”
11.15 – 12.00
Invited Speaker 4
Dr. Nurul Taufiqurrochman*, Indonesian
Nanotech Society
Title:”Nanotechnology Development Strategy
for Supporting National Industry in
Indonesia”
12.00 – 13.00 Lunch Break
13.00 – 15.00
Parallel Session Parallel Session
15.00 – 16.30
16.30 – 17.00 Closing Ceremony
17.00 – 19.00 Free Time
19.00 – 22.00 Conference Gala Dinner
The Third Basic Science International Conference - 2013 ix
Parallel Session Day One - 16 April 2013
Room 3: Mathematics
Time Paper
ID Author Title Moderator
13.00 -
13.30 Invited A/Prof. Dann Mallet
Investigating Chlamydia trachomatis
using Mathematical and
Computational Models
13.30 -
14.30
M01 Trisilowati, Scott
McCue, Dann Mallet
A cellular automata model to
investigate immune cell-tumour cell
interactions in growing tumours in two
spatial dimensions.
Edi
Cahyono
M02 Muhammad Syifa'ul
Mufid, Subiono
On the structural properties of Latin
squares in Max-Plus Algebra
M03
Moch. Aruman
Imron, Ch. Rini
Indrati, and Widodo
On Uniform Convergence of
Trigonometric series Under p-
Supremum Bounded Variation
Condition
M04
Erma Suwastika and
Intan Muchtadi-
Alamsyah
Generalized Dedekind Modules
M05 Nelly Oktavia A, S.Si,
MT
Object Representation on Geometry
Learning using Augmented Reality
Approach
Discussion/Questions/Answers
14.30 -
15.20
M06 Edi Cahyono
Temporal Data, Candle Stick
Representation and Temporal
Probability Density Function
Trisilowati
M07
Pasrun Adam, La
Gubu, and Edi
Cahyono
Statistical Characteristics of the
Dynamics of Jakarta Composite Index (JCI) Based on Short Term Data
Represented in Candle Sticks
M08
La Gubu, Jony Puspa
Kusuma, and Edi
Cahyono
Temporal Probability Density
Function of the Dynamics of United
States Dollar Relative to Indonesia
Rupiah
M09
La Ode Saidi, Rasas
Raya, and Edi
Cahyono
A temporal-probability density
function based on candle stick
representation data: The case of the
dynamics of Japan yen relative to
Indonesia rupiah
Discussion/Questions/Answers
The Third Basic Science International Conference - 2013 x
15.20 -
16.10
M11 Sri Subanti
An Application of Random Utility
Method for Economic Valuation on
Change of Tourism Quality (Case
Study : Gedong Songo Temple &
Muncul, Semarang Regency, Central
Java Province)
Mukhsar
M13 Lisa Nesti
APPLICATION OF STATISTIC
NON PARAMETRIC-FRIEDMEN
TEST IN TASTE TESTING OF
SNACK PRODUK
M15 Tony Karnain
Exploring the Metacognitive Skills of
Secondary School Students' Use
During Problem Posing
M16 Muhammad Rifki
Taufik
Role of Teacher and Mathematical
Concept to Build Student's Character
by Using 'Everyone is Teacher'
Method
M17 Nelly Oktavia
Adiwijaya
Object Representation on Geometry
Learning using Augmented Reality
Approach
Discussion/Questions/Answers
The Third Basic Science International Conference - 2013 xi
Parallel Session Day Two - 17 April 2013
Room 3: Mathematics
Time Paper
ID Author Title Moderator
10.00 -
11.00
M18
Ani Budi Astuti, Nur
Iriawan, Irhamah,
Heri Kuswanto
Higest Posterior Density for
Identifying Differences in Gene
Expression Microarray Experiments
Rita Diana
M19 Mukhsar, N. Iriawan,
B.S.S. Ulama, Sutikno
Full Conditional Distribution
Investigation of Bayesian Poisson-
Lognormal 2-Level Spatiotemporal for
Analysing DHF Case
M20
Preatin, Nur Iriawan,
Ismaini Zain, Wendy
Hartanto
Modelling interregional migration in
East Java : Selected Models
M21
Ida Mariati Hutabarat,
Asep Saefuddin,
Hardinsyah, Anik
Djuraidah
Estimation in measurement error
models on Cases of Malnutrition in
the Province of East Java
M22 I Nyoman Budiantara
and Rahmawati Pane
Non Trend Fourier Series Estimator In
Heteroscedastic Nonparametric
Regression
Discussion/Questions/Answers
11.00 -
12.00
M23 I Nyoman Budiantara,
Sony Sunaryo,
Mohamad Dokhi
On the Confidence Band of Local
Likelihood Estimates in Generalized
Poisson Regression Model
Ani Budi
Astuti
M24
K. Fithriasari, N.
Iriawan, B.S.S.
Ulama, Sutikno, H.
Kuswanto
Prediction of Hourly Rainfall using
Bayesian Neural Network with
Adjusting Procedure
M25 J.K. Wororomi, M.
Mashuri, Irhamah and
A. Z. Arifin
Vector Auto-Regressive Control Chart
and Its Application in Industry
M26
Rita Diana, I. Nyoman
Budiantara, Purhadi
and Satwiko Darmesto
Bayesian Confidence Interval for
Smoothing Spline in Nonparametric
Multivariable Regression Model
M31 Herlina Hanum Generalized Linear Model For
Estimating Aids Cases In Indonesia
Discussion/Questions/Answers
Scientific Papers
Invited Papers
The Third Basic Science International Conference - 2013 I01
S.K. Lai1,2
and P.J. Hsu1,2
1Complex Liquids Laboratory, Department of Physics, National Central University, Chungli 320, Taiwan
2Molecular Science and Technology Program
Taiwan International Graduate Program, Academia Sinica,
Taipei 115, Taiwan
The time development of the molecular shapes (configurations) of macromolecules may be generated by
the molecular dynamics simulation and used to calculate for each molecular shape its structural similarity
(with respect to a reference configuration) with the ultra-fast shape recognition technique. This idea of
using the ultra-fast shape recognition technique [1] to track down the motion of atoms stems from our
observation that there are fundamental differences in the dynamics of atoms between a bulk system and a
finite system such as a macromolecule. For concreteness, we test the generality of the technique by
studying disparate metallic clusters. In broad sense, we look upon the metallic clusters as
“macromolecules”. To gain deeper insight into the cluster dynamics, our calculations are carried out in
three steps: pin down firstly individual atoms of the cluster and compute from their instantaneous
configuration a distribution of atomic distances, calculate a shape similarity index parameter, and finally
construct the temperature dependent contours of a probability shape similarity index function. The physical
content of the contours of the latter function presents a new perspective in interpreting the temporal change
of microstates and the bearings they have in revealing microscopic panoramas of pre-melting and melting
transition. Specifically, we found a correlation between the temperature variation of the probability shape
similarity function and the change in cluster dynamics, and hence gaining a more precise picture of
melting-like scenarios. Perhaps most importantly is that the ultra-fast shape recognition technique can be
implemented for understanding the sub-structures of clusters whose characteristic features present the kind
of discernment that proves difficult to extract in laboratory and computer-simulation experiments.
Reference:
[1] P.J. Ballester and W.G. Richards, Proc Roy Soc A Math. Phys. Eng. Sci. 463, 1307 (2007).
Cluster Dynamics by Ultra-Fast Shape Recognition
Technique
The Third Basic Science International Conference - 2013 I02
Nurul Taufiqu Rochman*
Research Center for Metallurgy, Indonesian Institute of Sciences
*Chairman, Indonesian Society for Nano
Kawasan PUSPIPTEK Serpong, Tangerang 15314 Indonesia
E-mail: [email protected]
It is believed that nanotechnology will become the next industrial revolution. Indonesia, a country with
abundant of natural resources (minerals, biodiversities) and 4th
largest in population, has to take advantage
for development of nanotechnology. This required appropriate strategy regarding to Indonesia’s potential
and capability in advancing technology. This study overviews a current status on development and
implementation of nanotechnology in Indonesia. First, a brief story about nanotechnology initiation in
Indonesia is described. National activities including policy, program and funding are then reported and
followed by explanation of several activities in each ministry (Ministry of Research and Technology,
Ministry of National Education, Ministry of Industry, and Ministry of Agriculture). Pictures of
nanotechnology human resources, R & D programs and facilities, and application of nanotechnology in
national industry are also explained in brief. Several research results on nanotechnology at our group are
also highlighted. Finally, activities on standardization, commercialization and building public awareness
are mentioned. In addition, potential areas of cross-country R&D cooperation and collaboration in the field
of nanotechnology also are described. As recommendation, good synergy between academic-
business/industry-government and networking development within regional research institution will
accelerate nanotechnology progress in Indonesia.
Keywords: nanotechnology development strategy, national industry, natural resources
Nanotechnology Development Strategy for Supporting
National Industry in Indonesia
The Third Basic Science International Conference - 2013 I03
Kwang-Ryeol Lee, Ph.D ([email protected])
Director-general, Institute for Multiscale Convergence of Matter,
Korea Institute of Science and Technology, Seoul, Korea
Computational research has been of increasing importance in wide spectrum of modern science and
technology. However, nowhere more so than in nano-bio science where molecular or atomic level
understandings of its structure, dynamics and properties are essential. Center for Computational Science
at KIST is focusing on the computational research in nano and bio technology. We are also
emphasizing the collaboration with experimental research for the synergic effect between experiments
and calculations. In this presentation, I will discuss the most up-to-date research activities of CSC-KIST
with specific examples of the nano-scale surface phenomena in both bulk and low-dimensional
materials, the multi-scale investigation of CNT reinforced composite materials, and the efforts for the
development of nano-TCAD environment.
Role of Atomic Scale Computational Research in the
Nanoscale Materials Science
The Third Basic Science International Conference - 2013 I04
Hideo Tsuboi
Nagoya University, Japan
Abstract
Paeony root (Paeoniae radix; Shakuyaku in Japanese) is one of the most well-known herbs in China, Korea
and Japan and has been used as a medicine for more than 1200 years. Paeoniflorin (PF), a glucoside, is
known to be one of the principle bioactive components of paeony root. PF has been reported to have
immunoregulatory, anti-allergic, anti-inflammatory, cognition-enhancing, neuromuscular-blocking, anti-
convulsant, anti-hyperglycemic, anti-coagulant, and sedative effects. However, the effect to innerceller
signal transduction or the bioactivity in molecular level is still not investigated at all. I have been interested
especially in the effect of PF to our immuno system and its working mechanism. Today, I introduce PF as a
herbal medicine and it's bioactivity from immunological stand point.
Paeonilorin(PF) Strongly Effects Immuno System
The Third Basic Science International Conference - 2013 I05
A/Prof. Dann Mallet
Mathematical Sciences, Queensland University of Technology, Brisbane, Australia
Abstract
Chlamydia trachomatis is the most common sexually transmitted pathogen of humans, with over 90 million
new adult cases occurring worldwide each year. Left untreated, chlamydial infection may result in severe
detrimental effects on reproductive health, especially in women. Infection becomes problematic and
persistent when it progresses from the lower to the upper genital tract, but despite intensive research there
is still debate over the mechanisms by which this progression occurs. This has led to the development of
mathematical models of the spatial changes and dynamics involved in the infection process. Here we
present a brief discussion of C. trachomatis before illustrating the progress to date in mathematical
modeling of the pathogen.
Investigating Chlamydia trachomatis using mathematical
and computational models
The Third Basic Science International Conference - 2013 I06
Petr Solich
Department of Analytical Chemistry, Charles University, Faculty of Pharmacy, Hradec Kralove, Czech
Republic
Abstract
Analytical chemistry – as a part of chemistry - is playing critical roles in the understanding of basic science
to a variety of practical applications, such as biomedical applications, environmental monitoring, quality
control of industrial manufacturing, food analysis, etc. One of the major challenges facing the medicine
today is developing of new therapies that improve human health. To help address these challenges the
utilization of enormous modern analytical technologies and high-throughput automated platforms has been
employed in the last decade, in order to perform more and more experiments in a shorter time frame with
increased data quality.
Liquid chromatography – and chromatography in general as well - is without any doubts the most
important analytical methodology, combining both qualitative and quantitative analysis in one step. In the
last decade various analytical strategies have been established to enhance separation speed and efficiency in
liquid chromatography applications. Current trends in fast liquid chromatographic separations involve
monolith technologies, fused-core columns, high-temperature liquid chromatography (HTLC) and ultra-
high performance liquid chromatography (UHPLC). The high specificity in combination with high
sensitivity makes it an attractive complementary method to traditional methodology used for routine
applications.
Introduction of ultra-high performance liquid chromatography (UHPLC) in 2006 has brought a new
challenge and attract more and more scientists for development of new applications using liquid
chromatography. Together with this new instrumentation, a huge expansion of new stationary phases was
registered during the last decade. Several different technologies in stationary phases - with different
characteristics were introduced into the market. Introduction of sub-2-micro particles brought a new
challenge into laboratories. Extensive decrease of time of analysis and excellent separation efficiency
attracted manufacturers and scientists to look for new applications. Monolithic technology is based on a
unique sorbent material allowing good quality of separations in a minimal time. The main advantages of
monoliths, apart from short analysis time, are long lifetime and immense robustness, in most cases far
exceeding those of particulate columns. This new type of monoliths have at higher efficiency, better peak
symmetry and longer lifetime compared with particulate columns. Core-shell technology using porous shell
and solid core particles broke into market during last 5 years. These columns can be used in common
HPLC instruments as well as in UHPLC systems. This technology promises to increase of resolution and
maximizes throughput, and result in solvent saving and easier method transfer.
Application of UHPLC and various new stationary phases to the mainly bioanalytical analysis, but also to
environmental and pharmaceutical analysis will be discussed and examples of application to analysis of
real samples will be shown.
Recent Trends in Liquid Chromatography for Bioanalysis
Scientific Papers
Submitted Papers
The Third Basic Science International Conference - 2013
M01-1
Abstract—In practical system analysis and control system design,
many system models may be established in the form of the general
descriptor (singular) system, while they cannot be described by the
standard normal system form. Descriptor systems appear in many fields, such as electrical networks, power systems, aerospace
engineering, chemical processes, social economic systems, and so on.
The problem of input-output decoupling is one of the major control
design problems, since it aims to reduce a multi-input/multi-outputsystem to a set of single-input/single-output systems, thus
greatly facilitating the control strategy. In this paper, we study the
problem of the input-output decoupling for descriptor system. The
problem is handled in transfer function matrix setting. The necessary and sufficient conditions for a solution of the decoupling problem are
established and an algorithm for calculation of feedback gains is
presented. Finally, a structural interpretation is also given for
decoupled systems.
Keywords—Descriptor system, input-output decoupling,
transfer function matrix
I. INTRODUCTION
he study of decoupling linear time-invariant multivariable
systems has received considerable attentions in both
control theory and industrial practice for several decades.
It is well known that within a multivariable control systems,
every input affects several outputs resulting in a complicated
input-output relationship. Decoupling control strategies have
been developed for the transformation of coupled input-output
system to equivalent decoupled systems. System decoupling
or noninteracting control is one of the major problems in
multivariable system theory and has been extensively
discussed in a number of papers on linear regular systems[l-
5].Some literature has also appeared on the decoupling of the
descriptor systems [6-9].In this paper, we study the problem of
the input-output decoupling for descriptor system. The
problem is handled in transfer function matrix setting. The
necessary and sufficient conditions for a solution of the
decoupling problem are established and an algorithm for
calculation of feedback gains is presented. Finally, a structural
interpretation is also given for decoupled systems.
Consider the descriptor system defined by
(1)
where , and are the state vector, the
input vector and the output vector, respectively ; ;
; , E is singular. It is well known that the
existence and uniqueness of (classical) solutions to (1) are
guaranteed if (E,A) is regular, i.e., for some
. The system (1) is said to have index at most one
if the dimension of the largest nilpotent block in the
Kronecker canonical form of (E,A) is at most one [10].
Descriptor systems that are regular and of index at most one
can be separated into purely dynamical and purely algebraic
parts (fast and slow modes). If the index is larger than 1, then
impulses can arise in the response of the system if the control
is not sufficiently smooth [9, 10]. Therefore, in the design of
feedback control, one should ensure that the closed-loop
system is regular and of index at most one.
II. FORMULASION OF THE PROBLEM
In this study, an approach for the input-output decoupling
of descriptor system of the form is
presented. Here transfer function matrix approach is used. For
the existence of a solution to system (1), we assume that
, where s is the complex variable associated
with the Laplace Transformation, i.e., is assumed to
be a regular pencil matrix.
Let the transfer function matrix of system (1) be defined
as follows:
(2)
Here, we assume that , i.e., the system has an equal
number of inputs and outputs. Then, it is called single input-
single output decoupled if and only if is diagonal and
nonsingular.
Many feedback laws have been used in the regular system
case in order to achieve decoupling systems. Most commonly
used is the static state feedback law. If we apply state
feedback of the form
(3)
to the descriptor system (1), then the closed-loop system
becomes
(4)
The problem of decoupling the descriptor system (1) by
feedback (3) is to determine a state feedback matrix
and a nonsingular input transformation matrix
such that the pencil (E, A + BF) is regular and of
index at most one, and the closed-loop transfer function matrix
(5)
is nonsingular and diagonal.
III. BASIC CONCEPT
Before studying the input-output decoupling problem for
the descriptor system (1), we summarize the main results on
the input-output decoupling available in the some literature:
The input-output decoupling problem for linear time-invariant
systems of the form
(6)
Input-Output Decoupling Problem for Descriptor System:
Transfer Function Matrix Approach
Arman, Ari Suparwanto, and Salmah
T
The Third Basic Science International Conference - 2013
M01-2
with ; ; and nonsingular
has been investigated extensively over the last three decades
and is still attracting continuing interests [2, 3, 4, 5, 6, 9,
10,21]. In particular, because system (6) is equivalent to
we have the following theorem
Theorem 1(see [11]).
Given system (5) with E nonsingular, let be the ith row of C.
If
for some nonnegative integer j, then set.
j is integer satisfyin
};
Otherwise, set . Define
;
.
Then the input-output decoupling for system (6) is solvable if
and only if the matrix is nonsingular.
In this case, a solution pair ( , ) is given by
The following two lemmas are basic results for matrix pencils
and will be needed in the development to be given in the next
section.
Lemma 2. (See [12, 13])
Given , , and
withn nonsingular
(i). if and only if
, ;
(ii). assume
, .
Then
if and only if
, .
Lemma 3.
Given , , and
(i). ;
(ii). if and are of full row rank, then
The next lemma provides necessary and sufficient conditions
for a matrix pencilto be regular and of index at most one.
Lemma 4. (See [9, 10])
Let . The following statements are equivalent.
(i). is regular and of index at most one.
(ii). , where denotes a matrix
with orthogonal columns spanning the right nullspace of
matrix E.
(iii). .
IV. MAIN RESULTS
The purpose of this section is to present necessary and
sufficient solvability conditions as well as a numerically
reliable algorithm for the input-output decoupling of
descriptor system (1). For this purpose, first we transform the
input-output decoupling problem for descriptor system (1) into
the input-output decoupling problem for a linear time-
invariant system using orthogonal transformations.
Theorem 5. Given system (1), there exist nonnegative
integers and and ortogonal matrices
, and with
(7)
Such that , is
nonsingular, and
(8)
where and are nonsingular, and is of full
column rank for any .
In the following, we give a system interpretation of the form
(8). With respect to the coordinate transformations in the form
(8), the system (1) can be expressed as
(9)
where represents the transformed state vector and the
transformed input.
Let
, (10)
The Third Basic Science International Conference - 2013
M01-3
Then system (9) is equivalent to
(11)
Because is of full column rank for any ,
according to [22], we know
that:
, .
Consequently, is a redundant subsystem
(associated with constrained to be zero). As the redundant
subsystem has a zero trajectory = 0, we can delete this part.
Therefore, (1) is reduced to
• a regular subsystem (with nonsingular )
(12)
• an algebraic subsystem (associated with )
. (13)
The algebraic part of the system results in the algebraic
condition (13), which must be satisfied. This can be taken as
an algebraic constraint on the feasibility of the system (1).
Since is nonsingular, we can always find an input to
ensure that the descriptor system (1) is consistent. If we
consider
as a new input and choose , then
the regular subsystem (12) becomes
(14)
and the algebraic constraint (14) is satisfied.
The following lemma shows that the form (8) can be used to
characterize the existence of a feedback matrix F such that the
pencil (E, A + BF) is regular and of index at most one.
Lemma 6.Given a descriptor system of the form (1), there
exists a matrix F such that the pencil (E, A + BF)is regular and
of index at most one if and only if
, , . (15)
Proof: (see Delin Chu, 2006).
In the next result it will be shown that the input-output
decoupling problem for descriptor system (1) can be reduced
to the input-output decoupling problem for the linear time-
invariant system (14).
Theorem 7.Given a descriptor system (1), the input-output
decoupling problem for system (1) is solvable if and only if
the condition (15) holds and, furthermore, the input-output
decoupling problem for system (15) is solvable; i.e., there
exist matrices Fand Hwith Hnonsingular such that
is nonsingular and diagonal.
Proof. (see Delin Chu, 2006).
We obtain the following result, which presents explicit and
numerically verifiable necessary and sufficient solvability
conditions for the RRDP of system (1).
Theorem 8.Given a descriptor system (1) and assuming that
the forms (8) has been determined, then the following
statements are equivalent:
(i) The input-output decoupling problem for descriptor
system (1) is solvable.
(ii) (a). , , ,
(b). , is nonsingular,
and the input-output decoupling problem for linear
time-invariant system
(16)
is solvable.
(iii) The conditions in (a) and (b) above hold and
where is defined as follows.Let be the i-th row of . If
.
for some nonnegative integer j; then set
is integer satisfying
}
otherwise, set .. Define
. (17)
Theorems 7 and 8 can be used as a basis for devising a
numerically reliable algorithm for solving the RRDP for the
descriptor system (1) as follows.
Algorithm 1.
Input: Matrices E, A,B, and C of the system (1) with E
singular.
Output: Solution (F,H) of the input-output decoupling
problem for system (1) if the solution exists.
Step 1. Compute the form (8); check conditions in (a) of
Theorem 8(ii). If these
The Third Basic Science International Conference - 2013
M01-4
conditions are satisfied, go to Step 2; otherwise, conclude that
―The input-output decoupling problem is not solvable‖ and
stop.
Step 2. Compute the form (32); check condition in (b) of
Theorem 8(ii). If these
conditions are satisfied, go to Step 3; otherwise, conclude that
―The input-output decoupling problem is not solvable‖ and
stop.
Step 3. Verify the solvability conditions of the input-output
decoupling problem for the linear time-invariant system (16)
and compute a solution ( .
Step 4. Solve the 4 linear equations in (59) and (31) to get
(F,H). Output (F,H)and stop.
V. CONCLUSION
The decoupling problem for the descriptor systems by means
of state feedback has been studied using transfer function
matrix approach. The necessary and sufficient conditions for a
solution of the decoupling problem are established and an
algorithm for calculation of feedback gains is given.
REFERENCES
[1] Falb, P.L., and Wolovich, W.A.: ―Decoupling in the
designand synthesis of multivariable control
systems‖,IEEE Trans., 1967,AC-12, pp. 651-659
[2] Gilbert, E.G.: ―The decoupling of multivariable systems
by stateFeedback‖, SIAM J. Control, 1969, I, pp. 5&63
[3] Wonham, W.M., and Morse, A.S.: ―Decoupling and pole
assignment in lineare systems: a geometric approach‖,
SIAM J.Control, 1970.8, pp. 1-18
[4] Silverman, L.M., and Payne, H.J.: ―Input-output
structure oflinear systems with application to the
decoupling problem‖, SIAM J .Control, 1971, 9, pp.
199-233
[5] Paul, C.R.: ―Pole specification in decoupled systems‖,
Int. J .Control, 1972, 15, pp. 651-664
[6] Armentano, V.A. : ―Eigenvalue placement for
generalized linearSystems‖, Systems Control Lett., 1984,
4, pp. 199-202
[7] Christodoulou, M.A.: ―Decoupling in the design and
synthesisof singular systems‖, Automatica, 1986, 22, pp.
245-249
[8] Zhou, Z., Shayman, M.A., and Tarn, T.J.: ―Singular
systems:A new approach in the time domain‖, IEEE
Trans., 1987, AC-32, pp.42-50
[9] Dai, L.: ―Singular control systems - Lecture notes in
control andinformation sciences, 118‖ (Springer-Verlag,
1989)
[10] Bunse-Gerstner, A., . Mehrmann, V, and Nichols, N. K.
―Regularization of descriptor systems by derivative and
proportional state feedback‖, SIAM J. Matrix Anal.
Appl., 13 (1992),
[11] Chen, C.T., Linear System Theory and Design, Holt,
Rinehart and Winston, New York, 1984.
[12] Chu, D and Mehrmann, V., ―Disturbance decoupling
for descriptor systems by state feedback”, SIAM J.
Control Optim., 38 (2000), pp. 1830–1858.
[13] Chu, D and. Tan, R.,―Numerically reliable computing for
row by row decoupling problem with stability‖, SIAM J.
Matrix Anal. Appl., 23 (2002), pp. 1143–1170.
[14] Chu, D and. Hung, Y.S., ―A matrix pencil approach to
the row by row decoupling problem for descriptor
systems‖, SIAM J. Matrix Anal. Appl., 28 (2006), pp.
682–702.
Arman,
Ph.D student, Mathematics Department, Gadjah Mada University,
Yogyakarta, Indonesia.
Mathematics Department, Haluoleo University, Kendari, Indonesia
Ari Suparwanto
Mathematics Department, Gadjah Mada University, Yogyakarta, Indonesia
Salmah
Mathematics Department, Gadjah Mada University, Yogyakarta, Indonesia
The Third Basic Science International Conference - 2013 M02-1
Trisilowati, Scott McCue, Dann Mallet
Abstract- Cancer is still the leading cause of death worldwide. There is strong evidence in the literature for
the hypothesis that tumour growth is directly influenced by the cellular immune system of the human host
and this hypothesis is now generally accepted. For example, immune cells such as cytotoxic T
lymphocytes, natural killers and dendritic cells can identify and kill tumour cells. In this paper, a hybrid
cellular automata (HCA) model of the interactions between a growing tumour and the host immune system
is developed. While individual cells are modelled using a discrete, cellular automata description, the effect
of chemokines is introduced using a continuous partial differential equation (PDE) to describe the
concentration of chemokines secreted by the tumour. The numerical solution of the PDE model is
combined with a number of biologically motivated automata rules to form the hybrid model. We simulate
the growing tumour using this model in a number of in silico 'cancer patients' and present the results in
various ways including Kaplan-Meier survival-like curves.
A cellular automata model to investigate immune cell-
tumour cell interactions in growing tumours in two spatial
dimensions.
The Third Basic Science International Conference - 2013 M03-1
Abstract— Matrices L of size n × n are called Latin square if
every column and every row of L contain n different numbers.
And, Max-Plus Algebra is algebraic system using two operations,
max and plus. In this paper, we derive some properties of a Latin
square in Max-Plus Algebra and their eigenvalues and
corresponding eigenvector.
Index Terms— Latin square, Max-Plus Algebra, Eigenvalue,
Eigenvector.
I. INTRODUCTION
A Latin square of order n is square matrix of size n × n such
that every row and every column has n distinct numbers. For
convenience, we use n = {1,2,…,n}. The notion of Latin
square is firstly introduced by Leonhard Euler. A Latin square
is in reduced form if first row is [1, 2, 3, …, n] and first
column is [1, 2, 3, …, n]T. If numbers in both diagonals also
distinct then we called it by Latin square-X. An example of
Latin square and reduced Latin square is given below
321
213
132
213
132
321
The study of Latin square is mainly about discrete
mathematics aspect especially enumeration of Latin square.
Until now, the exact number of Latin square is known only for
1 ≤ n ≤ 11. The result of enumeration Latin square-X is can be
found in [1]. The number of Latin square of order 5 and 6 is
960 and 92160 respectively, and for order 7 the number of
Latin square is increasing sharply, that is 862848000.
Accordance with its name, Max-Plus Algebra is algebra that
using two operations, max and plus. In Max-Plus algebra
defined algebraic structure ),,( R where is set of
extended real numbers, i.e. }{ RR. In this paper, we
denoted infinite element, i.e. Operation max denoted
by and defined by },max{ baba , and operation plus
denoted by and denoted by baba for every a, b
inR . For example, 3}2,3max{23 and
46262 .
It is easy to show that both operations , are
commutative in max-plus algebra. Because all Rx satisfy
xxx and xxx 00 , then the zero and
unit element in max-plus algebra is and 0 , respectively.
The set of all mn matrices in max-plus algebra is denoted
by mnR
, and for 1m we denoted the set of all 1n vectors
by nR . Let mnRA
, the entry of A in ith row and j
th column
is denoted by jia ,and sometimes we write
jiA ,][ . The ith row
and jth column of A is denoted by
,][ iA and jA ,][
respectively. For mnRBA , BA is defined by
},max{][ ,,,,, jijijijiji babaBA
and for pmpn RBRA , , BA is defined by
)}(),...,(),max{(][ ,,1,22,,11,, jppjijiji bababaBA
For example,
320
41
211
A ,
21
150
13
B
We get
320
410
213
BA ,
513
663
404
BA
In max-plus algebra, we defined AAA 2 or
generally kk AAA 1 for ,...2,1k
Let nnε
RA , a digraph (directed graph) of A is denoted
as G(A). Graph G(A) has n vertices and there is an edge from
vertex i to vertex j if ija ,and this edge is denoted by (i, j).
Weight of edge (i, j) is denoted by ),( jiw and equal toija ,.
Sequence of edges ),(),...,,(),,( 13221 kk jjjjjj is called by
a path and if all vertices1321 ,...,,, kjjjj are different then
called by elementary path. Circuit is an elementary close path,
i.e. ).,(),...,,(),,( 113221 jjjjjj kCircuit that consisting of
single edge, from a vertex to itself, is called by looping.
Weight of a path ),(),...,,(),,( 13221 kk jjjjjjp is
denoted by wp || and equal to the sum of weight each edge.
Length of path p is denoted by lp || and equal to the number of
edges in p. Average weight of p is defined by
l
w
p
p
||
|| .
Any circuit with maximum average weight is called by
critical circuit. Graph G(A) is called strongly connected if
there is path for any vertex i to any vertex j in G(A). If graph
G(A) is strongly connected, then matrix A is irreducible. From
On The Structural Properties of Latin Square in Max-Plus
Algebra
Muhammad Syifa’ul Mufid, Subiono
The Third Basic Science International Conference - 2013 M03-2
matrix A, ji
kA ,][ is equal to the maximal weight of a path
with length k from vertex i to vertex j.
II. LATIN SQUARE IN MAX-PLUS ALGEBRA
Because the discussion is in max-plus algebra, it is allowed
to use infinite element as number/element of Latin
square. In this paper we define two types of Latin square:
a. Latin square without infinite element, the numbers that
used are in }...,2,1{ nn
b. Latin square with infinite element, the numbers that
used are in }1...,2,1,{ nn
The set of all Latin squares of order n without infinite element
is denoted by nLS and the set of all Latin squares of order n
with infinite element is denoted by nLS. Example of two types
of Latin square is given below.
We can infer that 4
1 LSL and 4
2 LSL .
III. PROPERTIES OF LATIN SQUARE IN MAX-PLUS
ALGEBRA
Properties of Latin square in max-plus algebra that will be
derived are:
a. Irreducible. Are all Latin squares in max-plus algebra
irreducible?
b. Close under operation . Are all Latin squares closed
under operation ?
c. Close under operation . Are all Latin squares closed
under operation ?
A. Property of Irreducibility
Lemma 1. All Latin squares are irreducible matrix.
Proof.
Let L be Latin square. If nLSL then all numbers of L are
finite. Therefore, in graph G(L) there is a path with length 1
from vertex i to vertex j for all nji , . Then we can conclude
that G(L) is strongly connected and consequently L is
irreducible.
If nLSL we consider matrix LLL 2 . Because there
is only one in every row and every column of L then
jiL ,
2 ][ is finite for all nji , . Therefore in graph G(L) there
are some paths with length at least 2 from vertex i to vertex j
for all nji , . Then we can conclude that G(L) is strongly
connected and consequently L is irreducible.
B. Property of closed under operation
We say that Latin squares are closed under operation if
for all Latin squares A and B, BA is Latin square.
Lemma 2. Let both A and B are in nLS or in nLS. BA is
Latin square if and only if BA .
Proof.
Let nLSBA , and BAC . Because nBA jiji ,, ][,][
then nBAC jijiji ,,, ][][][ . If C is Latin square then
nLSC . To prove A = B we only need considering first
column. See the illustration below
1,1,
1,21,2
1,11,1
1,
1,2
1,1
.
.
.
.
nnn ba
ba
ba
c
c
c
Let nxa 1,1, if xb 1,1
then x can appear more than one
or not appear in left side matrix. Therefore we get
1,11,1 ba and by same way we get 1,11,21,2 ,..., nn baba or
generally1,1, ii ba for all ni . Consequently, the first column
of A and B is equal or generally ii BA ,, ][][ for all ni , in
other word BA .
Conversely, if BA then
jijijijijijijiji aaaaabac ,,,,,,,, },max{
Consequently, AAABAC andC is Latin square.
For nLSBA , it can be proved by similar way.
By Lemma 2 we can conclude that Latin square is not closed
under operation
Example:
123
231
312
,
213
132
321
BA
We get
231
312
123
231
,
3241
1324
2413
4132
21 LL
The Third Basic Science International Conference - 2013 M03-3
223
232
322
BA
and BA is not Latin square.
C. Property of closed under operation
We say that Latin squares are closed under operation if
for all Latin square A and B, BA is Latin square. In other
word, there is Latin square C and natural number p such
that CpBA .
Lemma 3. If three Latin squares nLSCBA ,, satisfy
CpBA then np .
Proof. Let DBA , and D is Latin square, then
)}(),...,(),max{(][ ,,1,22,,11,, jnnjijiji bababaD
Because maximum value both kia , and jka , for all
nk are n , then maximum value of jiD ,][ is n2 . Next, we
determine the minimum value ofjiD ,][ .
Let kjkki dba ,,
then },...,,max{][ 21, nji dddD and
we know that
n
k
k nnd1
)1( . It is easy to find that the
minimum value of jiD ,][ occur when
1...21 nddd n,
then 1}1,...,1,1max{][ , nnnnD ji. If there are
some k such that 1 nd kthen there are some l such
that 1 nd l and consequently 1][ , nD ji
. So, it is clear
that minimum value of jiD ,][ is 1n .
Because D is Latin square of order n
and nDn ji 2][1 , , then we can conclude that
}|{}2,12,...,2,1{][ , nkknnnnnD ji
So, if CpD , we get np .
From Lemma 3, one of requirement for BA producing
Latin square is for all ni there is nj such that
]11..11[][][ ,, nnnnBA ji
So we can conclude that Latin square is not closed under
operation .
Example:
321
213
132
,
213
132
321
BA
We get
556
565
655
BA
and BA is not Latin square.
IV. EIGENPROBLEM OF LATIN SQUARE IN MAX-PLUS
ALGEBRA
Matrix L of order n has eigenvalue R and
corresponding eigenvector nnRv if both of them satisfy
vvL
In this paper we denoted )(A be eigenvalue of matrix A.
From [2,3], there is algorithm to find eigenvalue corresponding
eigenvector that called by Power Algorithm. If L is irreducible
matrix, then eigenproblem is equivalent to problem to find
critical circuit in G(L), where eigenvalue is equal to weight of
that critical circuit.
We define LL )( and
nLLLLL ...32
It can be proved thatjL ,][
is eigenvector of L if
0][ ,
jjL[3].
A. Eigenvalue of Latin square in Max-Plus Algebra
From Lemma 1, all Latin squares are irreducible matrix.
Therefore, to find eigenvalue of L we need to find the weight
of critical circuit in G(L).
If nLSL then },...,2,1{][ , nL jj and it is clear that
nL ji }]max{[ ,. Let
),(),,(),...,,(),,( 113221 jjjjjjjjp kkk
be critical circuit with length k with nk in G(L), then
knjjwjjwjjwp kkw ),(...),(),(|| 13221
and average weight of p is equal to
nk
kn
p
p
l
w ||
||
Because n occurs exactly one in every row and column of L,
we can ensure that average weight of critical circuit p is equal
to n. Therefore, eigenvalue of L is equal to n, in other word
n .
By the same method, we get eigenvalue of nLSL , that is
1 n .
B. Eigenvector of Latin square in Max-Plus Algebra
Let nLSA and nLSB . From the definition we get
AnA )(and AnB )1(
. It is clear that
average weight of critical circuit both in G(A) and and G(B) is
0.
From [3], if p is critical circuit of G(L) then for all vertices
in p satisfy 0][ ,
L . But in this case,
The Third Basic Science International Conference - 2013 M03-4
for nLSA and nLSB , the average weight of A and B is
equal to maximum value of matrix A and B, i.e
nAA ji }]max{[)( ,
and
1}]max{[)( , nBB ji .
Moreover, n occurs exactly one in every row and column of
A and 1n occurs exactly one in every row and column
of B . Consequently, there is always critical circuit in A such
that the initial vertex is i. The same condition is for matrix B .
Therefore, for all n in satisfy
0][ , A and 0][ , B
or in other word, all diagonal entries of both A and B are equal
to 0. So we can conclude that all columns of
A is
eigenvector of A and all columns of
B is eigenvector of B
Example.
4213
3124
1342
2431
A
We get 4)( A and
0231
1320
3102
2013
A
0121
1010
2101
1010
A
from
A we get three different columns and we can check that
all of them are eigenvector of A
1
0
1
0
4
3
4
3
4
1
0
1
0
A ,
2
1
0
1
4
2
3
4
3
2
1
0
1
A
0
1
2
1
4
4
3
2
3
0
1
2
1
A
V. CONCLUSION
In this paper we can conclude that Latin squares have
properties in Max-Plus Algebra, that is
1. All Latin squares are irreducible matrix
2. Latin squares are not closed under operation
3. Latin squares are not closed under operation
Moreover, eigenvalue of Latin squares L are equal to
maximum value of L and all columns of
L are eigenvector of
L.
REFERENCES [1] Mufid, M.S., 2012, Kajian Teori Permutasi and Its Application to
Enumeration of Latin Square-X and Sudoku-X (In Indonesian), Bachelor
Thesis, Mathematics and Natural Science Faculty, Institut Teknologi
Sepuluh Nopember, Surabaya.
[2] Subiono and van der Woude, J.W., Power Algorithm for (max, +)- and
Bipartite (Min, Max,+)-system, Discrete Event Dynamic Systems:
Theory and Application 10, pp. 369-389, 2000.
[3] Subiono, 2012, Aljabar Max-Plus dan Terapannya, Buku Ajar Mata
Kuliah Pilihan Pasca Sarjana Matematika, Institut Teknologi Sepuluh
Nopember, Surabaya.
The Third Basic Science International Conference - 2013
M04-1
Abstract
Let be trigonometric series for
. It is well known that if the nonnegative sequences
{an} is decreasing and , then
if and only if
We weaken the monotone condition in this classical result to the
so called p-supremum bounded variation condition and shows
the similar conclusion for uniform convergence of certain
trigometric series still holds.
Index Terms— p-supremum bounded variation,
trigonometric series , uniform convergence
I. INTRODUCTION
It is well known that there are several interesting
classical theorems in Fourier analysis having
assumptions determined by certain monotonicity of
the coefficients. The following classical convergence
result can be found in some monograph such as in
[1, 10].
Theorem 1.1. Suppose that is nonincreasingly
tending to zero. A necessary and sufficient condition for the
uniform convergence of the series
is
Tikhonov [8] introduced a class of General Motonotone
Sequences (GMS) as follows: A sequence
is said to be GMS if there exists such that the relation
holds for . He used a class of GMS to weaken the
monotonicity condition of coefficient (1.1) as stated in
Theorem 1.2.
Theorem 1.2. Let be non negative sequence
satisfying and . A necessary and
sufficient condition for the uniform convergence of the series
(1.1) is
The class of GMS was further generalized by Zhou
[9] to class of Mean Value Bounded Variation
Sequences (MVBVS) . A sequence is
said to be MVBVS if there exist and such that
holds for , where the greatest integer that a
less then or equal to x. He proved that Theorem 1.2 also
valid when the condition is replaced by
.
1 Mathematics, FMIPA, UB and Student Graduade School FMIPA, UGM 2 Mathematics, FMIPA, UGM 3 Mathematics, FMIPA, UGM
Further, in [6, 7] Liflyand and Tikhonov defined the
class of p-General Monotone Sequences . Let
and be two sequences of complex and
positive numbers, respectively, a couple if
there exist such that the relation
holds for and . Then Dyachenko and
Tikhonov [2] proved the following Theorem:
Therem 1.3. If and and.
Then necessary condition for the uniform convergence of the
series (1.1) is
For , if and only if [8].
As corollary, more general then GMS.
Futhermore, Imron, et al [3, 4] generalized MVBVS and
SBVS to (p-Mean Value Bounded Variation
sequences) and (Supremum Bounded variation
Sequences). Let and be two sequences of
complex and positive numbers, respectively, a couple
if there exist and such that
for p, and if there exist
and such that
for p, A little modification of definition of
is class .The couple is p-
Supremum Bounded Variation Sequences Second Type ,
written if there exist and
tending monotonically to infinity depending
only on such that
holds for p, .
Imron, et al [ 4] have shown that
. In the present paper, we
investigate the uniform convergence of trigonometric series
under p-Supremum Bounded Variation Condition.
On Uniform Convergence of Trigonometric Series Under
p-Supremum Bounded Variation Condition
Moch. Aruman Imron1, Ch. Rini Indrati
2, and Widodo
3
The Third Basic Science International Conference - 2013
M04-2
II . SOME PROPERTIES OF p-SUPREMUM BOUNDED
VARIATION SEQUENCES SECOND TYPE
In this section, we study some properties and
relation between and
Theorem 2.1. If and
decreasing monotone then
holds for p, .
Proof. We denote
for every . Given then we write
Theorem 2.2. If and
tending to zero then is
bounded variation.
Proof. Let and we
denote
Given then For every , there exists
such that for
Given and from proof Theorem 2.1. we
obtained
Thus
therefore is bounded variation.
Theorem 2.3. If , then
.
Proof. By Theorem 3.5 and Theorem 3.8 in [4],
. Now, we will show that
Let , there exists a
positive constant C such that
for , therefore . Thus
.
III. UNIFORM CONVERGENCE OF TRIGONOMETRIC
SERIES
In this section we investigate the uniform convergence of
trigonometric series under condition of class of .
We consider the series
and
where is a given null sequence of complex numbers,
i.e., as We define by f(x) and g(x) the sums of
series (4.1) and (4.2) respectively at the point where the series
converge.
Theorem 4.1. Let . If
,fo ,
then series (3.2) converges uniformly on .
Proof. We denote
Given then For every , there exists
such that for . Let be
nonincreasing null sequence such that , so
there exists such that for . Let
, by proof Theorem 2.2 we write
Let us now estimate , where
. By Abel’s transformation, we get
where and ,
.
By (3.3)
To estimate A, for any we can find such
that . Since
, if , then
and (3.3) imply
If , then we decompose A as
. Similar to (3.1) we
get
Further
The Third Basic Science International Conference - 2013
M04-3
where and
.
Since
then
From , we obtain
From (3.3), (3.4) and (3.5) we get
Thus, if given there exists such
that for
Series (3.2) converges uniformly on .
ii. For x = 0 , and from i , then (3.2)
converges uniformly on . The proof is complete.
Theorem 3.2. Let , if
, for , then series
(3.1) converges uniformly on .
Proof. The proof is similar to proof of Theorem 3.1. for
.
Corollary 3.3. Let . If
for and
, then series (3.2) converges uniformly on .
Corollary 3.4. Let . If
for and ,
then series (3.2) converges uniformly on .
Corollary 3.5. Let . If
for , then series (3.2) converges uniformly on
.
IV. CONCLUSION.
Under p-Supremum Bounded Variation Condition, the
sufficient condition of uniform convergence of trigometric
series is , for .
ACKNOWLEDGEMENTS
The authors gratefully acknowledge the support of the
Department of Mathematics FMIPA UB and the Graduate
School Department of Mathematics FMIPA UGM .
REFERENCES
[1] Chaundy, T.W. and Jollife, A.E., 1916, The Uniform
Convergence of certain class trigonometric
series, Proc. London, Soc. 15, 214-116.
[2] Dyachenko, M. and Tikhonov, S., General monotone
sequences and convergence of trigonometric
series, in: Topics in Classical Analysis and
Applications in Honor of Daniel Waterman
(World Scientific, Hakensack, NJ, 2008), pp.
88-101.
[3] Imron, M.A., Indrati, Ch.R.and Widodo, Sifat-sifat
Barisan dan fungsi dasri klas p-mean Value
Bounded variation, Konferensi Nasional
Matematika 16, Unpad , Bandung, 2012
[4] ] Imron, M.A., Indrati, Ch.R.and Widodo, Relasi Inklusi
pada Klas Barisan p-Supremum Bounded
variation, Jurnal Natural A ,No 1, Vol 1,
FMIPA, UB, Malang (Appear 2013).
[5] Korus,P., Remark On the uniform And L1-Convergence
Of Trigonometric Series, Acta Math. Hungar,
128(4), 2010.
[6] Liflyand,E. and Tikhonov,S., The Fourier Transforms of
General Monotone Functions, Analysis and
Mathematical Physics, Trends in Mathematics
(Birchauser, 2009).
[7] Liflyand, E. and Tikhonov, S., A concept of general
monotonicity and applications, Math Nachr,
284, No. 8-9, 2011.
[8] Tikhonov,S., Best approximation and moduli of
Smoothness computation and Equivalence
Theorems, Journal of Approximation Theory,
153 (19-39), 2008.
[9] Zhou, S.P., Zhou, P. and Yu, D.S., Ultimate generalization
to monotonicity for Uniform Convergence of
Trigonometric Series, http://arxiv.org/ abs/
math/0611805v1.
[10] Zygmund, A., Trigonometric Series, Vol I, II, Second ed,
Cambridge Univ. Press, 1959.
The Third Basic Science International Conference - 2013
M05-1
Abstract—Zafrullah defined generalized Dedekind domain and
Akalan defined generalized Dedekind prime ring to get a
polynomial ring that has same structure as its base ring.
Meanwhile the concept of Dedekind modules was defined by
Naoum and Al-Alwan by adapting the property of the ideals of a
Dedekind domain to submodules. In this paper we define the
concept of generalized Dedekind modules by adapting the
property of ideals of a generalized Dedekind domain to
submodules. We also show that and integral domain R is a
generalized Dedekind domain if and only if every torsionless R -
module is a generalized Dedekind module.
I. INTRODUCTION
HE structure of a ring may not be preserved on its
polynomial ring. For example, a polynomial ring over a
Dedekind domain is not always a Dedekind domain. Also a
polynomial ring over a Dedekind prime ring is not always a
Dedekind prime ring. To obtain a polynomial ring which has
the same structure as its base ring, the property of Dedekind
domain is weaken to a ring which is called a generalized
Dedekind domain (G-Dedekind domain, see [11]). Moreover,
one also generalize Dedekind prime ring into generalized
Dedekind prime ring (G-Dedekind prime ring, see [1]).
Akalan [2] has proved that if R is a G-Dedekind prime ring
with an automorphism of finite order, then ;R x is G-
Dedekind prime. In [10] we have shown the converse: that if
;R x is G-Dedekind prime then R is -G-Dedekind
prime, i.e., all reflexive -ideals are invertible. In [6] these
results have been generalized to generalized Asano prime rine
(G-Asano prime ring) where a G-Asano prime ring is a non-
Noetherian G-Dedekind prime ring.
Meanwhile the concept of Dedekind modules was
introduced by Naoum and Al-Alwan [7] as a generalization of
Dedekind prime rings. Following this introduction, the
structure and properties of this class modules have been
investigated in [8], [3], [9], and [5]. In [7] Naoum and Al-
Alwan have shown that for a faithful projective R -module
M , if M is a Dedekind module then M is finitely generated
and R is a Dedekind domain.
In this paper we introduce the concept of generalized
Dedekind modules (G-Dedekind modules). We call M a G-
Dedekind module if every reflexive submodule of M is
invertible. We also obtain the relation between G-Dedekind
domain and torsionless G-Dedekind modules as follows: a
maximal order R is a G-Dedekind domain if and only if every
torsionless R -module is a G-Dedekind module. A key result is
the relation between reflexive ideals of R and reflexive
submodules.
1 Erma Suwastika and Intan Muchtadi-Alamsyah is with Algebra Research
Group, Faculty of Mathematics and Natural Sciences, Institut Teknologi
Bandung
II. BASIC DEFINITION
Let R be an integral domain with field of fractions Q . For
any R -ideal A , we define
1A q Q qA R q Q Aq R
and * ,RA Hom A R . By [4] we can identify 1A and *A .
We define
1
1 1A q Q qA R
and ** *,RA Hom A R .
Once again we identify 1
1A
and **A . It is clear that
1
** 1A A A
.
An R -ideal A is reflexive if 1
** 1A A A
and it is
invertible if 1 1A A AA R . A ring R is a G-Dedekind
domain if R is an integral domain which every reflexive ideal
is invertible.
Now we generalized the above concept to modules. To begin
with, let M be an R module. Let S be a set of regular
elements of R , then 1RS be the total quotient ring and
0 for some implies 0T t S tm m M m . It is clear
that T is multiplicative subset of S . Hence we have the
quotient ring 1RT . We denote 1RT by Q . For any R -
submodule N of M , we define 1N q Q qN M . Then
1N is an R -submodule of Q satisfying 1R N and
1N N M . The R -submodule N is called invertible if 1N N M . According to Naoum and Al-Alwan [7], an R -
module M is called a Dedekind module if every submodule
of M is invertible.
For any R -module M we define * ,RM Hom M R and
** *,RM Hom M R . Any R -module M is called torsionless
if M can be identified as submodule of **M and it is reflrxive
if **M M .
We define G-Dedekind modules as follows.
Definition 1. Let R be an integral domain with field of
fractions Q defined as above and M be an R -module. We
say M a G-Dedekind module if every reflexive R -submodule
of M is invertible.
It is clear that every Dedekind module is a G-Dedekind
module.
Generalized Dedekind Modules
Erma Suwastika and Intan Muchtadi-Alamsyah1
T
The Third Basic Science International Conference - 2013
M05-2
III. MAIN THEOREM
If R is an integral domain, then we have ** *B A AB for
any R -ideal A and B . The following lemma shows that a
similar property holds.
Lemma 2. Let L be an R -module and A an ideal of R .
Then
1) ** *A L LA .
2) *
** ** * *L A A L .
Proof.
1) Let * * 1 *g A L A L . Then
1
n
i i
i
g q f
, where 1
iq A ,
*
if L , and n . Hence ,i i Rq f Hom L Q for all
1,2,...,i n . We will show that ,i i Rq f Hom LA R .
Let
1
k
j j
j
l a LA
where k . Then for all 1,2,...,i n ,
1 1 1
k k k
i i j j i i j j i i j j
j j j
q f l a q f l a q f l a R
, because
i j jf l a A . Hence *
i iq f LA and *
g LA .
2) Let ** **h L A . Then
1
n
i i
i
h b s
, where **
ib L ,
1
** 1
is A A
, and n . We will show that
* * ,i i Rb s Hom A L R for all 1,2,...,i n .
Let * * 1 *
1
k
j j
j
g q f A L A L
, where k . Then for
all 1,2,...,i n , 1 1
k k
i i j j i i j j
j j
b s q f b s q f R
,
because i js q R and ,i j j Rs q f Hom L R where
i j j j i js q f x f xs q for all x L . Hence
*
* *
i ib s A L and *
* *h A L . ▪
Lemma 3. Let M be a torsionless R -module and N be a
reflexive submodule of M . Then there exists a reflexive ideal
T such that MT N
Proof. Define T r R Mr N . By definition, MT N .
It is clear that /RT Ann M N , hence T is an ideal of R .
We will show that T is reflexive.
It is enough to show that **T T . First, as R is reflexive,
then ** **T R R .
Let **q T and m M . Then
** * **** ** ** * * **mq MT M T T M MT MT N N
since N is reflexive. We conclude that q T . ▪
The main theorem below shows that every torsionless
module over G-Dedekind prime ring is G-Dedekind module.
Theorem 4. Let R be an integral domain. The following
are equivalent:
1) R is a G-Dedekind domain.
2) Every torsionless R -module is a G-Dedekind module.
Proof. It is clear that (2) implies (1) since every reflexive
ideal of R can be considered as right submodule of RR , and
hence invertible.
Now we assume that R is a G-Dedekind domain. Let M
be a torsionless R -module. We will show that M is a G-
Dedekind module.
Let N be a reflexive submodule of M . It is clear that 1NN M . By Lemma 3, there exists a reflexive ideal T of
R such that MT N . Since R is G-Dedekind domain, then 1R TT . Since 1R M , we have
11 1 1 1 1 1M MRM M TT M MT T M N MT NN
. We conclude that N is invertible. ▪
For further research, it is interesting to see if we can also
define G-Asano modules and G-HNP modules.
ACKNOWLEDGMENT
The authors would like to thank Hanni Garminia for various
discussion on Dedekind modules.
REFERENCES
[1] E. Akalan, “On Generalized Dedekind Prime Rings”, Journal of
Algebra, 320 (2008), 2907-2916.
[2] E. Akalan, “Ore Extensions over pi G-Dedekind Prime Rings”,
Communications in Algebra, 39 (2011),594-600.
[3] M. Alkan, B. Sarac, and Y. Tiras, “Dedekind Modules”,
Communications in Algebra, 33 (5) (2005), 1617-1625.
[4] D. Eisenbud and J.C. Robson, “Modules over Dedekind Prime Rings”,
Journal of Algebra, 16 (1970), 67-85.
[5] H. Garminia, P. Astuti, and Irawati, “A Note on Dedekind Modules”,
International Journal of Algebra, vol. 5 no. 10 (2011), 491-498.
[6] H. Marubayashi, I. Muchtadi-Alamsyah, and A. Ueda, “Skew
Polynomial Rings which Are Generalized Asano Prime Rings”, preprint.
[7] A. G. Naoum and F. H. Al-Alwan, “Dedekind Modules”,
Communications in Algebra, 24 (2) (1996), 397-412.
[8] A. G. Naoum and F. H. Al-Alwan, “Dense Submodules of
Multiplication Modules”, Communications in Algebra, 24 (2) (1996),
413-424.
[9] B. Sarac, P. F. Smith. And Y. Tiras, “On Dedekind Modules”,
Communications in Algebra, 35 (5) (2007), 1533-1538.
[10] E. Suwastika, I. Muchtadi-Alamsyah, and Irawati, “Polynomials over G-
Dedekind Prime Rings”, Far East Journal of Mathematical Sciences,
vol. 58 issue 2 (2011), 173-178.
[11] M. Zafrullah, “On Generalized Dedekind Domains”, Mathematika, 33
(1986), 285-295.
.
The Third Basic Science International Conference - 2013
M11-1
Abstract— This study aims to determine the profit (loss)
earned economic actors tourism activities if the tourism quality
of Gedong Songo Temple and Muncul will be improved
(deteriorated). Change of tourism quality can be seen by
traveling expenses, natural environment, Javanese cultural
performances, and traditional markets. The method used to
measure changes in the economic benefits or economic loss with
random utility method. For Gedong Songo Temple, the study
found that traveling expenses, natural environment, and
traditional markets have significant factors about respondent
preferences to choose the change of tourism quality. For Muncul,
the study found that Javanese cultural performances have
significant factors about respondent preferences to choose the
change of tourism quality. Value of compensation received by
visitors as a result of changes in conditions improved by 2,482
billion Rupiah for Gedong Songo and 1,641 billion Rupiah for
Muncul. While the change in the condition deteriorated by 1,864
billion Rupiah for Gedong Songo and 1,352 billion Rupiah for
Muncul. Recommendation of this study for local government
should consider tourism quality factors in the formulation of
tourism development. Gedong Songo Temple (natural
environmental and traditional markets) and Muncul (Javanese
cultural performances).
Index Terms— economic valuation, gedong songo temple,
muncul, random utility method
I. INTRODUCTION
edong Songo Temple and Muncul are located in
Rawapening Area. They are administratively located in
Semarang Regency, Central Java Province, Indonesia.
Gedong Songo Temple located in district of Ambarawa.
Muncul located in district of Banyubiru. We can show the
location of Gedong Songo Temple and Muncul in figure 1.
Gedong Songo Temple and Muncul as a part of
Rawapening area will be developed Central Tourism in
Central Java especially on natural and history tourism
development for regional and national scale. Development of
Gedong Songo Temple and Muncul should have paid attention
from visitors preferences. It is important because changes of
tourism quality can provide multiple benefits, both tourism
actor (visitors) and tourism management (local government).
This study analyzed changes occurring conditions associated
changes of tourism quality.
It could be expected to affect the preferences of visitors
and potential visitors went to tourism object. The combination
of tourism quality called as attributes. From discussion group
and literature, we found four attributes to formulate changes of
quality in Gedong Songo Temple and Muncul.
Four attributes are: (a)travelling expenses, (b)natural
environment; (c) Javanese cultural arts performances, and (d)
traditional market. Four attribute were the basis to
accommodate hypothetical changes in Gedong Songo Temple
and Muncul. Thus, the hypothetical changes can be detected
gains or losses are received by the tourism actors in Gedong
Songo Temple and Muncul.
Based on this background, this study aims to determine the
profit (loss) earned economic actors tourism activities if the
tourism quality of Gedong Songo Temple and Muncul will be
improved (deteriorated).
II. METHODOLOGY
A. Method and Survey Instruments
In this study, the survey concentrated on the visitors in
Gedong Songo Temple and Muncul. We choose head of
household for interview. Respondents defined who use
tourism object for recreation and they must have paid the
entrance fee.
Interviewer were two undergraduate student. They have
trained to undertake the survey. Each of the trained
interviewers was responsible for one location where he/she
distributed the questionnaire to respondents, offered
explanations, and assistance in completing the questionnaire.
In total, 100 copies of the questionnaire were prepared and
distributed by interviewers. 86 questionnaires returned. It
could be used for analysis. From 86 questionnaires returned,
60 questionnaires for Gedong Songo Temple and 26
questionnaires for Muncul.
The questionnaire consisted of five sections, covering (1)
background and purpose of study, (2) motivations, desires, and
activities of the respondent in Gedong Songo Temple and
Application Random Utility Method for Economic Valuation on Change
of Tourism Quality (Case Study : Gedong Songo Temple & Muncul,
Central Java Province)
Sri Subanti(1)
, Rara Sugiarti(2)
, Endang Widiyastuti(3)
, and Arif Rahman Hakim(4)
G
Fig. 1. Location of Tourism Object : Gedong Songo Temple and Muncul,
Semarang Regency, Central Java Province.
The Third Basic Science International Conference - 2013
M11-2
Muncul, (3) respondent rating for visiting experience to
Gedong Songo Temple and Muncul, (4) demographic
information from respondents, (5) respondents rating for
attributes in Gedong Songo Temple and Muncul.
Questionnaire consisted of multiple choice questions,
dichotomous questions about current condition or hyphotetical
condition, and rank-ordered response. In addition there is also
an open question that is useful to provide further explanation
and to give support information from respondent.
B. Random Utility Method
Random utility method is a method of decomposing the
overall utility into two components, namely, deterministic
(observed utility) and random (utilities are not observed).
Utilities were not observed in the form of attributes that are
not observed, unobservable taste variation, error and imperfect
information, and the instrumental variables (McFadden, 1973
in Martha, 2008; Patunru, 2004).
Random utility model is used to overcome the
disadvantages of Contingency Valuation Method (Contingent
Valuation Method) which based on hypothetical behavior
directly. In the contingency valuation method, willingnes to
pay (WTP) or willingnes to accept (WTA) asked directly so it
is very possible that more assessment (overvalued) or even
less (undervalued). This can happen because the respondents
could not correctly convert their judgment in monetary units.
Therefore the WTP or WTA should be estimated, not
observed. Random utility models is one way to measure the
WTP and WTA indirectly (Patunru, 2004).
If known, there is a group of individuals n: i = 1, ..., i, ..., n.
For every opportunity to recreation, such individuals may
choose an alternative m which is part of a group of AP : j = 1,
..., j, ..., m.
Each individual has income (Mi) vectors and
socioeconomic characteristics (Si). Each AP has an attribute
environmental quality (Qj). Individual travel costs is Cji. In
this study, j and k represent alternative development (changing
conditions) in Rawapening. For individual i who chooses APj,
utilities can be formulated as follows:
Uji = Vji(Mi - Cji , Qj , Si) + ε ji ……................................…(2.1)
where, εji is the unobservable component of utility and
assumed to be random. Price of goods or services market
(other consumption) omitted to simplify notation. The model
can be formulated as mathematical function follows :
Chji=f(ASCji,TEji,NATENVji,JAVACULji,TRDMRKTji)..(2.2)
where, Ch is choice of respondent preference for hyphotetical
scenario (improved/deteriorated and current condition). ASC
is alternative spesific constant that used to divide choive
alternative i.e 1 represent change condition vice versa 0
represent current condition. TE is travel expense. NATENV is
natural environment. JAVACUL is javanese cultural
performance art. TRDMRKT is traditional market.
III. RESULTS
A. Demographic Profile of Respondents
Table I, for Gedong Songo Temple, the proportion of male
respondents (63.33%) than female respondents (36.67%). The
marital status of respondents with single status represent
66.67%. It’s greater than married status and not answer
represent 31.67% & 1.67%. Groups by age, majority
respondent between 21 – 30 years old represent 68.33%, for
respondent between 41 – 50 years old only 5%. Majority
respondents have attended senior high school represent
63.33%, eventhough many respondents have attended
university represent 25%. Respondents that have attended
junior high school or less represent 5%, whereas 6.67% of the
respondents had master degree.
From job sides, majority of respondents work as private
staff represent 53.33%. Based from respondent origin,
majority respondents cames from semarang regency with
66.67% and from others with 33.33%. Persons with a monthly
household income of 1.51 – 2.25 million rupiah and 2.25 – 3
million rupiah accounted for 23.33% and 1.67%. Majority
respondents with incomes less than 1.5 million rupiah
represented 75.00%.
Table II, for Muncul, the proportion of male respondents
(88.46%) than female respondents (11.54%). The marital
status of respondents with married status represent 65.38%.
It’s greater than single status represent 34.62%. Groups by age
divided into two, there are age groups between 21 – 30 years
old represent 69.23%, and between 31 – 40 years old represent
30.77%. Majority respondents have attended senior high
school represent 76.92% than attended university represent
23.08%.
From job sides, majority of respondents work as private
staff (50%), government staff (23.08%), and pension (26.92).
Based from respondent origin, majority respondents cames
from semarang regency with 84.62% and from others with
15.38%. Persons with a monthly household income of 1.51 –
2.25 million rupiah and 2.25 – 3 million rupiah accounted for
26.92% and 15.38%. Majority respondents with incomes less
than 1.5 million rupiah represented 57.69%.
The Third Basic Science International Conference - 2013
M11-3
B. Estimation Results
Based on Table III, for Gedong Songo Temple, the
attributes that affect the choice of respondents are travel
expense, natural environment, and traditional markets. For
Muncul, the attributes that affect the choice of respondents are
Javanese cultural performance art.
ASC variable indicates the average individual utility when
other variables unchanged. ASC value is positive for Gedong
Songo suggests the possibility of respondents would vote for a
new scenario (scenario improved) higher than the scenario
worse. This finding is somewhat different for the sub-region
appears likely scenario new respondents received lower. For
Muncul, respondents hope for a change in policy governance
of new attractions better. Both in terms of natural
environment, Javanese cultural performances, and traditional
markets.
Variable travel expense has a negative value and
significant in Gedong Songo Temple. Negative values indicate
a change scenarios selected respondent will decline as rising
travel cost incurred by the respondent. Travel expenses such
as admission price, consumption while in tourist attractions,
souvenir, hand pieces, travel place transformation, and other
costs (including toilets and parking). Different findings for
Muncul, because it is positive, the change of the selected
scenarios respondents tended to increase in line with rising
travel expense.
Natural environment variable is positive and significant in
Gedong Songo Temple. For Muncul is positive and not
significant. This value indicates the possibility of change
scenarios selected respondents will increase along with the
improvement of natural environment not only Gedong Songo
but also Muncul. Respondents appear increasingly aware of
the importance of natural environment when they are
conducting activities traveled.
Javanese cultural art performance is positive and
significant in Muncul. This value indicates the possibility of
change scenarios selected respondents will increase along with
the rise of Javanese cultural art performances held in Gedong
Songo Temple.
Traditional market variables is negative and significant in
Gedong Songo Temple. Different with this finding, for
Muncul is negative and not significant. This value indicates
the possibility of change in the selected scenarios of
respondents would decline with traditional market located in
Gedong Songo Temple. Based on these findings, the
respondents did not pay much attention souvenir or handmade.
Visitors choose a tourist attraction that has a beautiful natural
environment, can interact with the local community, Javanese
TABLE I
DEMOGRAPHIC PROFILE OF RESPONDENTS
IN GEDONG SONGO TEMPLE
Characteristics Freq. Percentage
Sex
Male 38 63.33
Female 22 36.67
Age
18 - 20 10 16.67
21 - 30 41 68.33
31 - 40 6 10.00
41 - 50 3 5.00
Marital Status
Single 40 66.67
Married 19 31.67
Not Answer 1 1.67
Monthly Household Income
(in Rupiah) 1US$ = Rp 9730
<= 1,5 million 45 75.00
1,51 - 2,25 million 14 23.33
2,25 - 3 million 1 1.67
Respondent Origin
Semarang Regency 40 66.67
Others 20 33.33
Education
Junior High School or Less 3 5.00
Senior High School 38 63.33
Graduate 15 25.00
Master 4 6.67
Occupation
Student 2 3.33
Government Staff 13 21.67
Private Staff 32 53.33
Entrepreneur 13 21.67
TABLE II
DEMOGRAPHIC PROFILE OF RESPONDENTS
IN MUNCUL
Characteristics Freq. Percentage
Sex
Male 23 88.46
Female 3 11.54
Age
21 - 30 18 69.23
31 - 40 8 30.77
Marital Status
Single 9 34.62
Married 17 65.38
Monthly Household Income
(in Rupiah) 1US$ = Rp 9730
<= 1,5 million 15 57.69
1,51 - 2,25 million 7 26.92
2,25 - 3 million 4 15.38
Respondent Origin
Semarang Regency 22 84.62
Others 4 15.38
Education
Senior High School 20 76.92
Graduate 6 23.08
Occupation
Government Staff 6 23.08
Private Staff 13 50.00
Pension 7 26.92
The Third Basic Science International Conference - 2013
M11-4
cultural art performance, and affordable with income
respondents.
Calculation of compensating surplus obtained by the
attributes used in the study (the natural environment, Javanese
cultural art performances, and traditional markets). Attributes
are determined by comparing the change in the conditions of
new scenarios to the status quo scenario. New scenario is
defined as a scenario, while improving the status quo scenario
is defined as the scenario gets worse or no change.
Compensating surplus received visitors at Gedong Songo
Temple amounted to Rp 2.482 billion for improved scenario
compared with worsened scenario Rp 1.864 billion. For
Muncul, the compensating surplus received visitors amounted
to Rp 1.641 billion for improved scenario than worsened
scenario amounted to Rp 1.352 billion.
IV. CONCLUSION & RECOMMENDATION
A. Conclusion
First, only three attributes affect the preferences of
respondents in choosing the changing conditions in Gedong
Songo Temple. There are travel expense, natural environment,
and traditional markets. For Muncul, only Javanese cultural
performance art.
Second, the compensation surplus received visitors due to
changing scenario of the region improved Rawapening higher
than the scenario worse. Value scenarios improved
compensation amounted of Rp 2.482 billion for Gedong
Songo Temple and Rp 1.641 billion for Muncul. While the
worsening scenario amounted of Rp 1.854 billion for Gedong
Songo Temple and Rp 1.352 billion for Muncul.
B. Recommendation
First, the government needs to reformulate development
policies in Gedong Songo Temple and Muncul. Natural
environment and traditional market as the main visitor
preference needs to be improved in Gedong Songo Temple.
For Muncul, Javanese cultural performance art needs to be
improved.
Second, the development of cultural tourism and natural
tourism can be applied for development of Gedong Songo
Temple and Muncul. Development of natural environment
combined with an increased frequency of Javanese cultural
performances earned positive response. It can be good
combination to increase rates for visitors and prospective
visitors in future.
ACKNOWLEDGMENT
Authors thanks to Local Government of Semarang Regency
and Surveyor Team for support this study.
REFERENCES
[1] Ben-Akiva, Moshe and Steve R Lerman. Discrete Choice Analysis :
Theory and Application to Travel Demand. MIT Press, 1985.
[2] Fauzi, Akhmad. Natural Resources and Enviromental Economics :
Theory and Aplication (in Bahasa). Jakarta. Gramedia, 2004.
[3] Freeman III, A. Myrick. The Measurement of Environmental and
Resources Values: Theory and Methods. Washington 1993..
[4] Gujarati, Damodar. Basic Econometrics 5th Edition. New York.
Macmillan Publising Company, 2009.
[5] Hakim, Arif Rahman, Sri Subanti, dan Mangara Tambunan. Economic
Valuation of Nature Based Tourism Object in Rawapening, Indonesia :
An Application of Travel Cost and Contingent Valuation Method.
Journal of Sustainable Development. Vol 4 No 2, April 2011. [Online].
Available: http://www.jsd.com
[6] Martha, Luhur Fadjar & Arianto A Patunru, (2007). “Measuring
Economic Value of Change of Tourism Environment in Tanjung Pinang
: An Application of Random Utility Model (Presented Conference Paper
Style)”, presented at Economic End Year Simposium, Depok, Indonesia,
December 13, 2007., Indonesia.
[7] Patunru, Arianto A. “Three Essays on Choice Based Estimations of The
Economic Benefits of Contamined Site Cleanup”. PhD Dissertation,
Dept. of Agricultural and Consumer Economics, University of Illinois,
Urbana-Champaign, United States, 2004.
TABLE III
ESTIMATION RESULTS WITH RANDOM UTILITY METHOD
Variable
Muncul Gedong Songo
n=26 n=60
ASC
-1.6368 * 0.6474
-0.9056 -0.6047
TC
0.0501
-0.8708 ***
-0.2256 -0.1537
NATENV
0.2433
0.8732 ***
-0.2283 -0.1576
JAVACUL
0.4582 ** 0.1652
-0.2265 -0.1527
TRDMRKT
-0.0733
-0.3792 ***
-0.1872 -0.1288
LR chi2 7.7300
83.1100
Prob > chi2 0.1720
0.0000
Pseudo R2 0.0130 0.0570
( ) : standard error
*** : sign α = 1% ** : sign α = 5%
* : sign α = 10
The Third Basic Science International Conference - 2013
M13-1
Lisa Nesti, Akademi Teknologi Industri Padang
Abstract. Snack food industry in West Sumatra is
currently facing various problems. Quoted in the Daily
Express Padang (Wednesday, 11/05/2011) that according
to the Governor of West Sumatra, West Sumatra opening
Food and Craft Fair IV, on the first floor of Industry
Ministry building on Tuesday (10/5) snack food industry
production of West Sumatra are still limited the market
share of traditional and not been able to get in modern
markets. This is because the packaging has not been so
good, the quality has not been homogenized to a certain
standard, and less varied types of products, as well as a
limited production capacity. Therefore, the author is very
interested in the theme of Innovation Taste diversified
products with a case study Emping Malinjo Pariaman by
using statistical non-parametric Friedman test. Friedman
test is one of the nonparametric tests using the k-related
samples (K-related sample), the method is based on the
data pairs k sampled at least ordinal, is used to test the
null hypothesis that the samples were drawn from the
same population. Friedmen test this, the data generated
into a two-way table with N rows and k columns where
rows represent different subject pairs and columns
represent a wide range of conditions. This test data is
ranking, the scores in each row are ranked separately. The
hypothesis used is: H0: There is no difference in taste
preference level for the four different flavors crackers and
H1: At least there is one kind of flavor chips that have a
different level of preference.
Test of love for the four different flavors crackers
(original flavor, spicy sweetness, flavor and taste of
chocolate butter paprica) using 7 hedonic scale. By
processing SPSS statistical values obtained Friedman
(Chi-Square observation) of 14.139. By setting the real
-square table so
that the null hypothesis is rejected 11.3 (r2 observation
X2,t-1 table) and conclusion at least there are one kind
of flavor chips that have a different level of preference.
chips taste is preferred by respondents paprica
Keywords: organoleptic, non-parametric statistics, Test
Friedmen
I. INTRODUCTION
1.1.Background
Development and empowerment of small businesses in order
to restore national ekomoni plays a fairly important, it can be
seen from the overall number of small businesses in
Indonesia by 40 million to the workforce and contribute 88%
to the national Gross Domestic Product of 38.9% ( Dep.
Industry). Nonetheless, small business development,
empowerment in order to increase the product selling many
constraints, the constraints due to several factors including:
limited capital, limited qualified human resources and lack of
capacity in science and
technology in processing and designing high value products.
Especially for snacks industry in West Sumatra is currently
facing various problems. Quoted in the Daily Express
Padang (Wednesday, 11/05/2011) that according to the
Governor of West Sumatra, West Sumatra opening Food and
Craft Fair IV, on the first floor of Industry Ministry building
on Tuesday (10/5) snack food industry production of West
Sumatra are still limited the market share of traditional and
not been able to get in modern markets. This is because the
packaging has not been so good, the quality has not been
homogenized to a certain standard, and less varied types of
products, as well as a limited production_capacity.
Although small businesses face obstacles in the competition,
but small business is quite a lot of advantages, one of which
is the ability of small businesses to the potential advantages
as an object to generate revenue. Lodging in West Sumatra
(Sumatra), the small business sector of the economy
kerupakan highest and best interests of the people of West
Sumatra, namely 99% of the total number of small
businesses that exist in West Sumatra (Sumatra Industrial
Service). On this basis the Government of West Sumatra
with local governments conducting training and small
business development through excellent products in each
region. Flagship program draws on the advantages of each
region in terms of geography, climate and culture.
In this study, researchers conducted a study with the object
of research Pariaman Emping Malinjo. According to sources
from the Ministry of Industry, West Sumatra in 2002 that
there were 658 SMEs (Small Medium Enterprises) in
Kab.Padang Pariaman with flagship product is the Small
Business Emping Malinjo. Efforts in Pariaman malinjo chips
are quite well known in West Sumatra due around this area
grow quite a lot of rods malinjo fruitful seasonally and
fruitful enough to motivate people to make a light meal, but
progress in the sense that can not be eaten immediately and
packaged potluck. Therefore encourage investigators to the
theme of research on diversification Taste Product
Innovation with case studies Emping Malinjo Pariaman
using statistical non-parametric Friedman test.
1.2.Limitation Problem
In this study, four different flavors using only the original
flavor chips, spicy sweetness, flavor and taste of chocolate
Application of Statistic Non Parametric-
Friedmen Test In Taste Testing Snack
The Third Basic Science International Conference - 2013
M13-2
butter paprica using hedonic scale 7 is: It does not like, do
not like, kinda do not like, neutral, somewhat like, like, very
like
1.3.Problems
The problem of this research is to know the four
different flavors of chips that taste is the most preferred by
consumers. By using hypothesis:
H0: There is no difference in taste preference level for the
four different flavors crackers
H1: At least there is one kind of flavor chips that have a
different level of preference.
II. LITERATURE REVIEW
2.1. Organoleptic Test
Organoleptic Test is also known as assessment of sensory or
sensory assessment is a subjective assessment of the oldest
ways is very commonly used to measure the quality
attributes of a commodity by using humans as a
measurement tool based on the ability penginderaannya the
eyes, nose, tongue, skin, ears (BN Polli, 2007). Organoleptic
assessment in research applications are numerous, including:
assessment of the shelf, matching products, mapping
products, product specifications, product formulation, testing
irregularities potential odor and appearance of foreign odors
and determine keterterimaan products. In the food industry,
measurement characteristics of food quality is essential as
the basis of food quality control program development.
Foodstuffs or food received by humans on the basis of
certain characteristics that describe the taste, feeling and
perception resulting from the factors of physical appearance,
kinestetika and flavor. Included in the physical appearance
factor adlah color, size, shape and physical damage. Factors
kinestetika go round texture, viscosity, consistency, feeling
and touching the mouth with a finger. While the flavor factor
is the combination of smell and taste sensations.
2.2.Test-hedonic
Hedonic properties of a further psychological reactions of a
panel after he recognized that the arrest of the sensory
properties of food products that are served by declaring the
form of a personal response like: like it or not, accept it or
not accept, for better or worse, good or bad. ( Irma and
Cahyo, 2007). Besides, they also noted the level of likes and
dislikes so-called hedonic scale as in the case of love,
hedonic scale can have such profound love, love, a little
love. Conversely responses do not like to have such hedonic
scale: rather do not like, do not like, very unhappy and very
very unhappy. Hedonic scale can be stretched or reduced
according to the desired scale. In the analysis of hedonic
scale was transformed into a numerical scale with the
number rising by level of preference. The number penelis
used for hedonic test was sebayak 20-25 people to panelists
somewhat trained while using untrained panelists sebayak 80
people or more. (Soekarto,1992).
2.3. Nonparametric Statistical Data Analysis for
Organoleptic Test: Test Friedman
Statistics known as nonparametric statistical distribution of
free, does not need the assumption that the population is
normal spreads or other assumptions about the distribution of
the population. Nonparametric statistics is very well used for
data categorical (qualitative) or ranking (discrete) with a
simpler calculation. Friedman's analysis is one of the
nonparametric tests using the k-related samples (K-related
sample), the method is based on the data pairs k sampled at
least ordinal, is used to test the null hypothesis that the
samples were drawn from the same population. Friedmen
test this, the data generated into a two-way table with N rows
and k columns where rows represent different subject pairs
and columns represent a wide range of conditions. This test
data is ranking, the scores in each row are ranked separately.
The hypothesis used is:
H0: Each rank of treatments in the same group.
H1: At least one treatment that is different from others
Statistical_formulation:
r2 observation = (12/Nk (k-1)) (Rj)
2 – 3 N (k +1)
Description: r2 observation = Statistics Friedman, N =
many lines, k = Lots of columns,
Q = number of ranking of the i-th treatment
DecisionRule:
H0 is rejected if: r2 observation X
2,t-1 table , that tells us
there at least one treatment that is different from others H0 is
accepted if: r2 observation < X
2,t-1 table which means the
ranking of treatments in each group is thesame .
III. RESULTS AND DISCUSSION
Introduction to Descriptive Statistics Taste Typical Emping
Of the four kinds of flavor chips are tested to 80 panelists
consisting of original flavor chips, chocolate chips butter,
crackers and chips taste sweet spicy flavor paprica results
obtained 96.3% stated that the original chips (not supplied
various flavors) there is a sense of a typical empingnya, only
3.8% expressed no distinctive flavor chips. This suggests that
the original chips were just fried without being offered a
variety of flavors characteristic flavor was very subtle
empingnya.
For chips that have been given chocolate butter, only 32% of
the panelists said it was no distinctive flavor chips, while
67.5% said there was no longer distinctive flavor empingnya.
This suggests that the cocoa butter flavor given has given
them a distinctive flavor chips dominant than themselves.
Given chips spicy sweeness, as much as 37.5% of the
panelists said it was no distinctive flavor chips, while 62.5%
said there was no longer distinctive flavor empingnya. This
suggests that the taste of brown sugar and chili had given
impart a distinctive flavor chips dominant than themselves.
While Emping given a sense of paprika, 75% of panelists
said it was no distinctive flavor chips while 25% said there
was no longer distinctive flavor empingnya. It is shown that
the peppers were given not impart a distinctive flavor chips
dominant than themselves.
The Third Basic Science International Conference - 2013
M13-3
4.3.2. Organoleptic Assessment Test Against passions sense
Liking for the fourth test chips using 7 different flavors
hedonic scale,It does not like, do not like, kinda do not like,
neutral, somewhat love, love, very love.
Friedman test was used in this study to determine
whether there is any difference in the level of the four kinds
of taste preferences is tested chips panelists. The hypothesis
used is:
H0: There is no difference in taste preference level for the
four different flavors crackers
H1: At least there is one kind of flavor chips that have a
different level of preference
The results obtained with SPSS is:
Table 4.1. Output of SPSS of Friedman test
N 80
Chi-Square 14.139
Df 3
Asymp. Sig. .003
From Table 4.2 Statistical values obtained Friedman (Chi-
Square observation) of 14.139. By setting the real level of
1% ( = 0.01) obtained by chi-square table 11.3 that the null
hypothesis is rejected (r2 observasi X
2,t-1 tabel ) and
concluded there is at least one kind of chips that have a sense
of different level of preference.
Of the 80 panelists average of 21.3% expressed a great love
of the original flavor chips, the next 17.5% expressed love to
taste chocolate chips butter, 16.3% said very like the spicy
sweet flavor chips and 31.3% expressed love to taste paprica
chips. In general it can be said that the chips taste paprica
highly preferred by 80respondents.
IV.CONCLUSION
From the research that has been done can be concluded that
the facts on the ground suggest that there is no desire of the
producers to innovate product chips. This is because the
resulting raw crackers always sold out, in addition to the
limitations in the processing of fast chips. From the
organoleptic tests against a variety of flavors provided
crackers (original flavor, sweet taste spicy, buttery chocolate
taste and flavor paprica) can be stated that the passions of the
sense, we can conclude there is at least one kind of flavor
chips that have a different level of preference ie crackers
taste paprica greatly liked by the respondents
REFERENCES
[1] Balance Economic Daily, 12 October 2002. “Raising
Tanamanmalinjo.”
[2] Horizon Daily, 17 June 2004. Diversification
Buahmalinjo Processing Technology.
[3] Isnafia Arief, Irma, 2007. Hedonic test. Ministry of
Industry.
[4] Industrial Services of West Sumatra, 2002. List of Small
Business Distribution and Employment in West Sumatra
in 2002.
[5] Kompas, 19 April 2002. So determination Regional
Basis malinjo
[6] Ministry of Industry, 2002. Industry Data / Business
Processing of Horticulture in Indonesia.
[7] Polli, B.N, 2007. Organoleptic assessment. Ministry of
Industry.
[8] Power Home Biz Guide, 2006. 10 Tips To Attract
Consumer Packaging Buying Products. Virginia USA
[9] Sinar Harapan, 2003. Copyright Design Products
[10] Suryati, Tuti, 2007. Organoleptic Data Analysis
Parametric and Nonparametric.
Ministry of Industry.
The Third Basic Science International Conference - 2013 M15-1
Tony Karnain, Md Nor bin Bakar and Hossein Mohammadikia Mathematics Education/Universiti Teknologi Malaysia
Abstract: The purpose of our study was to explore students’
use of metacognitive skills during problem posing activities.
This qualitative research explored the metacognitive skill of 21
secondary school students in a rural area while posing
individually mathematical problems. Thinking-Aloud
protocol was conducted during the problem posing activities.
The audio recordings of Thinking-Aloud protocol for the
students provided the data to address this question. Analysis
of their written work and thinking-aloud protocols provided
evidence of how students used metacognitive skills while
problem posing and revealed different levels of these skills.
Analyses of the Thinking-Aloud protocol also provided
evidence for the metacognitive skills associated with planning,
monitoring, and evaluation. The students used planning and
monitoring skills equally. Furthermore, different levels of
sophistication of planning were apparent. Students who
combined these metacognitive skills demonstrated a higher
level of monitoring. However, from our analyses that there
was considerable overlap in the metacognitive activities
associated with monitoring and evaluation.
Keywords: Metacognitive skill, problem posing, secondary
school students.
I. INTRODUCTION
Today, one of the main goals of education is to make
the students gain the thinking skills and strategies which
they will use throughout their lives, rather than storing
information [1]. Likewise, mathematics education must
provide opportunities for students to develop their ability to
think and reason critically, and this should be done through
sharing and reflecting on how students think through and
reason about a problem [2]. One alternative to develop
mathematical power in students is through the generation of
mathematical problems (problem posing) by the students
themselves [3]. Children‟s expression of mathematical ideas
through the creation of their own mathematics problems
demonstrates not only their understanding and level of
concept development, but also their perception of the nature
of mathematics [4]. Subsequently, from a teaching
perspectives, many researchers also have noted that
students' posed problems can be useful to teachers in
assessing students' understanding of mathematics ( [5], [6],
[7]).
Problem posing has long been recognized as an
important pedagogical tool in the teaching of mathematics
([8], [9], [10]). It includes an approach of teaching students
how to think analytically and how to analytically examine
the world they live [11]. It has also been argued that
problem posing promotes a deep understanding of
mathematics ([5], [12], [13]). Elementary teachers have
used posing tasks to gain insights into their students'
mathematical understanding for the purpose of guiding
instruction (e.g., [5], [14]). In his research [15] argued that
the first function of problem posing aproach is to help
students think like mathematicians by posing their own
mathematical questions and trying to solve them. This could
lead to “new” knowledge constructed by the students.
Many reasons have been voiced for utilizing
problem posing in mathematics instruction. For example, in
real-world situations, problems often are not coherently
stated and students need to learn to identify them and
formulate them more clearly ([9], [16]). It can lead to more
student-centered [5] and student inquiry oriented [17]
instructional practices. Development of skills in recognizing
problem structure and analogical reasoning ([18], [19]).
Mathematical problem posing has been attracting
keen attention of the mathematics education community for
more than three decades [20]. For instance, In his doctorate
dissertation,[21] argued that by adopting the “Problem
Posing Approach” students tended to be innovative, skilful
and knowledgeable and problem solvers. Then, Problem
posing activities have also improved student‟s activities,
motivation and achievement in learning mathematics [22].
Furthermore, [12] believed that problem posing can change
the orientation of mathematics lessons from a goal of
finding the correct answer and recording an appropriate
method, to finding the correct question from a infinite array
of imaginative possibilities. Most studies have shown that
problem posing can provide a positive impact on students
([23], [24], [25], [26], [27]). In short, by empowering
students with knowledge regarding their intention to pose
problems, it is more likely that they will acquire the skills
and resources necessary to effectively solve problems and,
in turn, use these higher-level skills to their life [28].
Subsequently, successful completion of
mathematical problem also requires more than the
application of knowledge, it requires the combination and
coordination of both cognitive strategies and processes and
metacognitive behavior [29]. More recently, the
Partnership for 21st
Century Skills has identified self-
directed learning as one of the life and career skills
necessary to prepare students for post-secondary education
and the workforce [30]. Students‟ metacognitive skills can
be improved through explicit instruction ([31], [32]). Such
instruction is most effective when teachers incorporate it
into subject specific learning activities ([33], [34]).
Educators can incorporate a variety of instructional
strategies to promote the development of students‟
metacognitive skills. Reference [35] found that deep
conceptual learning was characteristic of students who
Exploring the Metacognitive Skills of Secondary School
Students‟ Use During Problem Posing
The Third Basic Science International Conference - 2013 M15-2
demonstrated the metacognitive skills of knowing what the
task requires, planning a strategy, monitoring their progress,
and self-checking their work. Furthermore, [36] reported
students‟ use of metacognitive skills enabled them to
transfer past knowledge to unfamiliar problems.
The concept of metacognition has been considered in
recent years in the field of education and as a concept that
is worked on [1]. In mathematics education, the major goal
of implementing metacognitive is to help students develop
knowledge and awareness of their own thought processes
[37]. This link between metacognition and problem posing
has also been found in the mathematics classroom. In a
sense, metacognition has an important place in the
education of children and adults alike ([38], [39]). Students
without metacognitive approaches are basically learners
without direction to review their progress, complishments,
and future directions [40]. In addition, developing students‟
metacognitive abilities can also assist to inspire innovative
and creative minds. [26]. in other words, metacognition
enables students to work on self-learning, helping them take
responsibility for their own learning especially in
mathematics [37]. In conclusion, using metacognitive skills
can have high impact on mathematics performance of
learners, even when controlled for the influence of
intelligence ([41], [42]).
Our research has been designed to gain insight into
students‟ use of metacognitive skills in relation to their
problem posing activities. By using data sources that
include a think aloud protocols and students written works,
We endeavored to capture a rich picture of students‟
thinking while problem posing. This research has potential
to enrich our understanding of how students apply
metacognitive skills during problem posing activities.
II. METHODOLOGY
This qualitative study examined the metacognitive
skills of secondary school students‟ use while problem
posing activities. This study involved 21 students in a rural
area in Kepulauan Riau (Indonesia). Since the aim of the
study was to examine the metacognitive skills rather than
simply assess mathematics expertise, it was necessary to
supply a nonroutine problem that would challenge the
students. Verbatim transcriptions of the audio recorded
Thinking-Aloud protocol were completed for 2 of students.
Our analyses of the transcripts were guided by the coding,
seeking patterns, and theme analysis methods described by
Patton [43].
The purpose of the Thinking-Aloud protocol was
twofold. First, the sessions were part of the intervention by
giving the students an opportunity to become more aware of
their thinking while problem posing by articulating their
thinking. Second, these sessions provided a source of data
to address the research question to examine the
metacognitive skills students use while problem posing.
After students written works were analyzed, The two
problem posers were individually interviewed to probe the
metacognitive skills that occurred during problem
posing.and to examine particularly the responses to
statements implicitly assessing the metacognitive processes
expressed by the students while posing the problem. An
open ended question is given to the student adopted from
Stickles [44].
Parking Lot Flyers Instrument
The SpreadtheWord Advertising Company needs to
distribute flyers for ten different businesses. They are going
to place the flyers on cars in the parking lot at a nearby
shopping mall. There are 1000 cars in the lot. The
businesses each have their own flyer. The LotaMoney
Company is paying for flyers for all the cars. Consequently,
a worker places a flyer on each of the 1000 cars for them.
The rest of the businesses cannot afford one flyer for each
car. A second business can afford one flyer for every other
car. Consequently, a second worker places a flyer from the
second business on every other car starting with the second
car in the lot. A third business can afford one flyer for every
third car, and a worker places a flyer from the third business
on every third car starting with the third car in the lot, and
so on. How many cars would be necessary so that one car
would get all 10 flyers?
Using the above problem, pose some related problems.
Fig.1 Example of Problem-Posing Question from the Parking Lot Flyers
Instrument (Cited from Stickles, 2006)
III. RESULTS AND DISCUSSION
During the activity, We observed that all students in the
class were actively engaged in posing the problem. A small
number (2 out of 21 or about 9.52%) of the students posed a
problem, and the rest of those did not contain sufficient
information to solve the problem. Examples of the
problem-posing statements posed through problem
generation for the Nested Squares instrument are in Figure
2.
Problem:
A teacher set up 15 baskets. He asked the students to
throw a ball in each basket, the second student to throw a
ball in every other can, the third student to throw a ball in
every third basket, and so on. How many baskets would
have at least 5 balls in them when all 15 students have
went?
Fig. 2 Examples of Problem-Posing Statements from the Parking Lot
Flyers Instrument
The students retained their focus throughout the
duration of the activity, and they were persistent in their
attempt to work through the problems. The transcripts of
the audio recorded of two case students provide additional
support for tha data analyses. We used the planning,
monitoring, and evaluation metacognitive categories to
guide our analyses of the students‟ data. We begin with an
overview of each type of metacognitive category. We
interpreted statements that referred to the given
information, goal of the problem, or selection of relevant
strategies as planning. For example, “Okay let me write
down what I know first”(S1). Monitoring was
characterized by the “in the moment” checking of their
work at intermediate stages. For example, “I need to make
sure it‟s suitable”(S1). Evaluation was characterized by
The Third Basic Science International Conference - 2013 M15-3
statements about the verification of the final answer. For
example, “if the answer I get makes sense”(S2). Our
analysis revealed that the students demonstrated planning
and monitoring equally for thinking aloud problem posing
protocols.
A. Planning
Examination of the transcript excerpts We coded as
planning revealed the following metacognitive skills:
making sense of the task, extracting the given information,
being aware of the goal, seeking any examples used in the
past, and mapping a solution. Within some of these skills,
We noted varying levels of sophistication in the way the
students employed planning strategies. We begin with
evidence of the students trying to make sense of the
problem before launching into their solution to the new
problem. Statements that demonstrated this were: “Let me
think of what‟s this”(S2) and “I‟ve to write down
everything first so that I can get an idea of it”(S1). I‟m
thinking there‟s numbers in there that were not doing
anything right, but I don‟t know if they‟re relevant (S2).
The students were able to identify the goal of problem.
Commonly, the students restated what was asked in the
problem. The language used to express this included, “I‟ve
got to determine” (S2), “I need to find out” (S1) , and “I
need to find” (S2). Two comments stood out as being more
interpretive. S1 expressed the goal of the problem in his
own words showing that he had a clearer understanding of
the problem. He said, “So I need to find out how many...”.
A component of planning demonstrated by the students was
their identification of previous strategies that were relevant
to the current problem. At an elementary level, the student
referred to his notes in search of examples of related
problems. As an example, (S1) commented “Give me one
second, I‟m just going to grab my book. Okay. See most of
the examples were converted to combination ”. S2 took this
a step further, identifying the way in which a past problem
was different from the current problem: Okay, so what I
used to do was find the total of cars. S1 and S2 varied in the
way they made use of previously learned strategies. At the
simplest level, the students had a tendency to execute
familiar questions without thinking through how that
question would link to other steps that would eventually
satisfy the goal of the question. Using previous knowledge
in this way hindered the learners from moving forward in
the new question.
B. Monitoring
Three types of metacognitive monitoring emerged
from our analysis of the thinking aloud protokol transcripts:
screening, and justification and a little revision. All
monitoring began as screening where the students checked
an intermediate action. Students exemplified screening with
statements like, “Wait, I‟ll check if it can be solved” (S1),
“Oops, that doesn‟t make sense” (S2). Other types of
monitoring were coupled to screening. We noted a number
of instances where after screening, the students justified
why a question did or did not make sense. In the following
excerpt, S2 recognized that the question obtained was
reasonable because it was in the expected domain. S2: Is
that the reasonable question? S1: Well that would make
sense because the numbers are almost similar with the first
question and I need to start it from here. (S1 and S2). The
following exchange between S1 and S2, demonstrated
screening followed by revision. S1and S2 suspected an
error, and S2 corrected the mistake.
S1: But that‟s wrong I think.
S2: Let me try another sentences
S2: Oh! That‟s what went wrong.
In a number of cases, the students alluded to the need
to revise their approach but did not immediately know how
to redirect their efforts. One example of this occurred when
S2 commented, “Okay well that‟s really frustrating because
I can‟t find the solution of the first question because I don‟t
know what‟ the exact formula”. Other instances of this were
signaled by language like: “just one second I‟ve got to think
about this” (S1), and “I have to think it in my head” (S2).
C. Evaluation The students‟ comments about their new question to
the problems revealed two levels of evaluation: intuition
and reason. First, We present one example of what We
interpreted as intuition. Common to these examples was the
students‟ “feelings” that the answers were right or wrong.
She concluded the session with, “I think I‟m going to go
with permutation. I‟ve got a good feeling” (S2). In the
following discussion, S2 presents two hunches. Initially, S2
mistakenly thought that the new question was a permutation
could be the answer. After further consideration S2
suspected that a more rigorous approach to try to solve the
new problem is required. S1 suspected that his solution was
not question because it was based on an assumption. S1
noted, “And then, I assume but I didn‟t really, I don‟t
know, I think I missed something”. The students also using
reasoning to evaluate their answer. S1 understood that the
final answer for the problem could be checked by
comparing its topic. In addition, S2 realized that his
attempt to find the result of the new question did not match
the goal of the first problem. He commented, “Yeah but it‟s
asking for the number of cars. That‟s not the correct one”.
IV. IMPLICATIONS AND CONCLUSION
The thinking aloud protocols provided evidence of
how students used metacognitive skills while problem
posing and revealed different levels of these skills.
Analyses of the Thinking aloud protocols provided
evidence for the metacognitive skills associated with
planning, monitoring, and evaluation. The students used
planning and monitoring skills equally. Planning skills
included making sense of the problem, extracting the given
information, identifying the goal, seeking any examples
used in the past, and mapping a solution. Furthermore,
different levels of sophistication of planning were apparent.
Lower level planning was demonstrated when students
restated the goal. In contrast, higher level planning was
demonstrated when students interpreted the goal, compared
the context for their use of strategies in the past to the
context of the new problem. Students‟ different levels of
planning reflect the characteristics of novice and expert
The Third Basic Science International Conference - 2013 M15-4
problem solvers described by Heyworth [45]. The students
demonstrated monitoring when they screened for errors,
justified their judgments, and made revisions to correct
wrong turns. Students who combined these metacognitive
skills demonstrated a higher level of monitoring described
by Delvecchio [46]. A part of this process included periods
of reflection when the students took time out from
executing actions to think about what revision actions they
would pursue next. Students‟ attention to thinking before
acting was evidence that they valued metacognitive
activities as part of their problem posing process. The
students demonstrated evaluation through their comments
on the correctness of their final question. The students
showed two levels of evaluation: intuition and reason.
Intuition was the students‟ sense of the correctness of a
solution. Reason was demonstrated when students
elaborated on why a solution was correct or not. Students
who were able to explain why an answer was incorrect
demonstrated a deeper analysis of their solution to the
problem. Reference [47] supports the importance of
students‟ analysis of errors as a means to reduce conceptual
errors. It is apparent from my analyses that there is
considerable overlap in the metacognitive activities
associated with monitoring and evaluation. Both involve
students checking their work. In the case of monitoring,
students check intermediate actions, and during evaluation
they check a final answer. Metacognitive evaluation
includes students proposing alternate solutions and
reflecting on what new things they learned by attempting
the problem.
ACKNOWLEDGMENT
The authors acknowledge with thanks for the
research facilities availed at SMAN SIANTAN
(KABUPATEN ANAMBAS INDONESIA) during the
experiment and preparation of this paper.
REFERENCES
[1] F.Aydin, “Geography teaching and metacognition,” Educational
Research and Reviews (Academic Journals). Vol.6, pp.274-
278,March 2011.
[2] K. C. Pope,” Metacognitive development in a college level
geometry course for pre-service elementary techers: A Case Study,”.
Doctoral Dissertation, Oklahoma State University, Stillwater,
Oklahoma, July 2011.
[3] E. Zakaria, and N. Ngah, “A Preliminary Analysis of Students‟
Problem-Posing Ability and its Relationship to Attitudes Towards
Problem Solving,” .Vol.3,pp. 866-870, September 2011.
[4] N. F. Ellerton, and P. C. Clarkson, “Language Factors in
Mathematics Teaching,” In: Bishop A J et al International
Handbook of Mathematics Education. Kluwer Academic Publishers,
Netherlands.
[5] A. T. Barlow, and J. M. Cates, “The Impact of problem posing on
elementary teacher‟s beliefs about mathematics and mathematics
teaching,” School Science and Mathematics,Vol. 106, pp. 64-73.
February 2006.
[6] P. Lin, “Supporting Teachers on Designing Problem-Posing Tasks
as a Tool of Assessment to Understand Students' Mathematical
Learning,” PME 28, Bergen, Norway, July 14-18.
[7] Z. Toluk-Ucar, “Developing preservice techers understanding of
fractions through problem posing,” Teacher and Teacher Education,
Vol. 25,pp.166-75. January 2009.
[8] S. Brown, and M. Walter, The Art of Problem Posing. Philadelphia:
Franklin Press, 1983.
[9] J. Kilpatrick, Problem formulating: Where do good problems come
from? In A. H. Schoenfeld (Ed), Cognitive science and mathematics
education (pp 123–147). Hilsdale, NJ: Lawrence Erlbaum. 1997.
[10] V. A. Krutetskii, The psychology of mathematical abilities in school
children. (J. Teller, trans. & J. Kilpatrick & I. Wirszup, Eds.).
Chicago: University of Chicago Press. 1976.
[11] H. Akay, and N. Boz, “The effect of problem posing oriented
analyses-II course on the attitudes toward mathematics and
mathematics self-efficacy of elementary prospective mathematics
teachers,‟ Australian Journal of Teacher Education, Vol.3,pp. 59-
75. February 2010.
[12] S. Brown, and M. Walter, The art of problem posing (3rd Ed).
Hillsdale, NJ: Lawrence Erlbaum, 2005.
[13] D. L. English, “Engaging students in problem posing in an inquiry-
oriented mathematics classroom‟. In F. K. Lester (Ed.), Teaching
mathematics through problem solving: Prekindergarten-grade 6,pp.
187-198, Reston, VA: National Council of Teacher of Mathematics,
2003.
[14] P. Whitin, „Promoting problem posing explorations‟. Teaching
Children Mathematics, 180, 7, November 2004.
[15] K. Y. Wong, “Use of students mathematics questioning to promote
active learning and metacognition,‟ 12th International Congress on
Mathematical Educatio, COEX, Seoul, Korea, 8 July – 15 July,
2012.
[16] National Council of Teachers of Mathematics, Principles and
standards for school Mathematics. Reston, Va: Author, 2000.
[17] E. A. Silver, “Fostering creativity through instruction rich in
mathematical problem solving and problem posing‟, ZDM-The
International Journal on Mathematics Education, vol.97, 75-80.
1997.
[18] L. D. English, “Development of seventh grade students‟ problem
posing”. In E. Pehkonen (Ed.), Proceedings of the 21st annual
conference for the International Group for the Psychology of
Mathematics Education, 2, 241-248. Lahti, Finland: University of
Helsinki and Lahti Research and Training Center. 1997b.
[19] E. Stoyanova, “Problem posing in mathematics classrooms”. In N.
Ellerton & A. McIntosh (Eds.) Research in mathematics education
in Australia: A contemporary perspective,pp. 164-185. Perth: Edith
Cowan University, 1998.
[20] I. Kontorovich, B. Koichu, R. Leikin, and A. Berman, “An
exploratory framework for handling the complexity of mathematical
problem posing in small groups”. Journal of Mathematical
Behavior, Vol.31,pp. 149-161.2012.
[21] A.Kwakwa, Teachers asked to adopt problem posing. GNA.
http;//ghananewsagency.devonet.com/details/education/teachers-
asked-to-adopt-problem-posing-approach/?ci=9&ai=36707, 2012.
[22] Nor Bakar & K.Tony, „Kemahiran Pengutaraan Masalah (Problem
Posing) Bagi Pelajar Sekolah Menengah Di Kabupaten Bintan
Indonesia‟, Journal of Edupres, Vol.1, pp. 173-186, September
2011.
[23] R. Abu-Elwan, „The Development of Mathematical Problem Posing
Skills for Prospective Middle School Teachers‟,(Accessed on: April
20, 2011).
[24] A.A.Nicolaou, and G.N. Philippou, „Efficacy Beliefs, Problem
Posing and Mathematics Achievement”, In: Pitta-Pantazi, D. and G.
Phillippou, (Eds.), Proceedings of the V Congress of the European
Society for Research in Mathematics Education Larnaca,
Department of Education, University of Cyprus, Cyprus, pp: 308-
317. 2007.
[25] C. Bonotto, “Realistic mathematical modelling and problem
posing”, University of Padova, Padova.
[26] Md Nor Bakar, & Ilfi Norman, “The role of metacognitive abilities
in posing mathematical problems”, Journal of Science and
Mathematics Education, Vol.5, pp.1-10. March 2012.
[27] S. Wiseman, “Problem posing as a padagogical startegy: A teacher‟s
perspective”, Dissertation, Illinois State University.Illinois,
December 2011.
[28] Y.E. Tatag, “Level of student‟s creative thinking in classroom
mathematics”, Vol. 6,pp. 548-553. July 2011.
[29] H.A. Hammouri, "An investigation of undergraduates„
transformational problem solving strategies:
Cognitive/metacognitive processes as predictors of holistic/analytic
strategies,”. Assessment & Evaluation in Higher Education, Vol.28,
pp.571-586. 2003.
The Third Basic Science International Conference - 2013 M15-5
[30] E.R. Lai, “ Metacognition: A literature Review”, Research Report.
TMRS staff. 2011.
[31] H. J. Hartman, “ Developing students‟ metacognitive knowledge
and strategies,” In H. J. Hartman (Ed.), Metacognition in learning
and instruction: theory, research, and practice (pp. 33-68).
Dordrecht, The Netherlands: Kluwer Academic Publishers. 2001a.
[32] G. Schraw, “Promoting general metacognitive awareness,” H.J.
Hartman (Eds.), Metacognition Learning and Instruction (pp.3-16).
USA: Kluwer Academic Publisher. 2001.
[33] J. Case, and R. Gunstone, “Metacognitive development as a shift in
approach to learning: An in-depth study,”. Studies in Higher
Education,Vol. 27,pp. 459-470, Marc 2002.
[34] M. E. Gredler, Learning and Instruction (6th ed.). Upper Saddle
River, New Jersey: Pearson Education, Inc. 2009.
[35] A. Haidar, and A. Naqabi, Emiratii high school students‟
understandings of stoichiometry and the influence of metacognition
on their understanding,” Research in Science & Technological
Education, Vol.26,pp. 215-237. 2008.
[36] E. Kapa, “Transfer from structured to open-ended problem solving
in a computerized metacognitive environment,” Learning and
Instruction, Vol.17, pp.688-707. 2007.
[37] Nelson, “The effectiveness of metacognitive strategies on 8th grade
students in mathematical achievements and problem solving skills,”
faculty of the graduate school, southern university and A&M
college. Dissertation. 2012.
[38] B. Kramarski, Z. R. Mevarech, and M. Arami, “The effects of
metacognitive instruction on solving mathematical authentic tasks,”
Educational Studies in Mathematics, 48, 225– 250. 2002.
[39] A.H. Schoenfeld, Mathematical problem solving. San Diego:
Academic Press. 1985.
[40] J. M. O'Malley, A.U. Chamot, Stewner-Manzanares, G., R.P.Russo,
and L. Kupper, “Learning strategy applications with students of
English as a second language,” TESOL Quarterly,Vol. 19,pp. 557-
584. March 1985.
[41] M. van der Stel, and M.V.J. Veenman, “Relation between
intellectual ability and metacognitive skillfulness as predictors of
learning performance of young students performing tasks in
different domains,” Learning & Individual Differences, Vol.18, 128-
134. January 2008.
[42] M.V.J.Veenman, R. Kok, and Blo¨ te, “The relation between
intellectual and metacognitive skills at the onset of metacognitive
skill development” Instructional Science, Vol.33,pp.193–211.
2005.
[43] M.Q.Patton, Qualitative research and evaluation methods.
Thousand Oaks, CA: Sage. 2002.
[44] P.R. Stickles, “ An analysis of secondary and middle school
teachers‟ mathematical problem posing,” doctoral dissertation,
University of Indiana, June 2006.
[45] R.M. Heyworth, “Procedural and conceptual knowledge of expert
and novice students for the solving of a basic problem in
chemistry,” International Journal of Science Education,Vol. 21,
pp.195-211. 1999.
[46] F. Delvecchio, “Students‟ use of metacognitive skills while problem
solving in high school chemistry,” Doctoral Dissertation, Queen‟s
University, Kingston, Ontario,Canada, August 2011.
[47] B.Kramarski, and S. Zoldan, “Using errors as springboards for
enhancing mathematical reasoning with three metacognitive
approaches,” Journal of Educational Research,Vol. 102, pp.137-
151. 2008
The Third Basic Science International Conference - 2013 M16-1
Abstract— Education is manifestation of civilization. One
of the education processes which are important is character
education. A factor which must be paid attention to in
character education is teacher. In learning process, teacher
has the important role to build the attitude and cognitive
ability of the students. Teacher as the educator is not just
transferring knowledge but also transferring value. It is
important to develop the learning that can give positive
contribution in character establishment, for example by
mathematics.
It is often to find that a mathematics teacher is just giving
the materials without giving the value or the sense of
mathematical concept. In developing the character which
can be built in mathematics, a teacher should understand
every character in mathematical concept. If teachers
understand the mathematics character, so they can establish
the values of every mathematical concept. This mathematical
concept can establish the discipline, visionary, responsible,
consistent and honest characters.
In this journal, the writers use ‘everyone is teacher’
method which can give the opportunity for students to have a
role as a teacher for their friends. By using this method,
everyone in class can get material and value not only from
the teacher but also from students and others. So it will be
formed the generation that has high quality of intellectual
and golden characters. This method is very useful for
students because this method is watching, speaking,
listening, writing, drawing, and emotional activities..
Index Terms— character, education, mathematical concept,
students, teacher
INTRODUCTION
Education in Indonesia influence to the nation achievement
very much. Education has close meaning with the teacher.
Teacher influence the students directly. The education quality
that‟s got is based on teacher quality. Teacher having honest
and straightforward in delivering knowledge to the students
will be a good teacher.
Having good intention is the result of the teacher‟s
character. Strong and good character will make the teachers
can be followed by the students. The teacher‟s character will
influence the effective learning system. The teacher‟s
characters that are patient, distinct, confident will deliver
knowledge well and will be the model for the students.
According to Fatmawati, in her paper - nowadays, the
obstacle of character establishment is the conventional
teaching technique underlay the learning process. Just using
books, the teacher dominate in class very much and teacher
haven‟t be able to make good interaction between the teachers
and students.
The teacher‟s duty is not only transferring knowledge but
also transferring value. Teachers help the students to find their
character. It needs teacher‟s character which is good to
establish student‟s character which is good because teacher is
the model for their student.
In order to make student‟s characters which are the same
with the mathematical character, the teachers teach by
transferring mathematical concept to the students.
REVIEW OF
LITERATURE AND RATIONALE Teacher‟s character
To get high quality and golden generation is needed moral
character of the teacher. The moral character means giving
good example to the students. The characters can be paid
attention in their daily attitude. Teacher is a leader in the class.
In relation with the leader, Calabrese and Roberts in The
International Journal of Education Management (2002:229)
explain that a leader with good character can give advantages
for his self and the people around him. On the contrary, when
a leader is weak in character so it will give lost for his self and
the people around him. The teacher position as the leader in
the class is prosecuted to have good character.
Good character make the teacher can be the model for the
students. According to Ryan Dand Lickona which is quoted
Research in Character Education (2008:45), character is an
individual which is good moral and done consistently. The
statement is supported by Sherman which is quoted by
Calabrase and Roberts in The International Journal of
Education Management (2002:229) that someone‟s character
appears from the individual behaviour which is in an action
form that will be repeated in the future.
The teacher‟s character can be made a model for the
students easily when the students do their duties in the class
which involve heart, mind, and action (Bassiouny, 2008:45-
Role of Teacher and Mathematical Concept to Build
Student‟s Character by Using „Everyone is Teacher‟
Method
Muhammad Rifki Taufik1, Eprina Eksa Gutami
2
1) Mathematics Education, Mathematics and Science, UNY, Yogyakarta, [email protected]
2) Mathematics Education, Mathematics and Science, UNY, Yogyakarta, [email protected]
The Third Basic Science International Conference - 2013 M16-2
46). Because of the sincereity in delivering knowledge, good
character, and the appropriation with the value and norm, can
motivate the students to have good character.
Mathematical concept Concept and Contextual that have the same meaning from
mathematics is an abstract mathematical object. Mathematics
uses zero symbols for meaning and mathematics thinking way
is based by axiom and deductive reasoning (Juhartutik, 2011)
Wardhani (in Nur, 200:2) said that mathematics learning
which is full of concept press on context abstractly. In
mathematics, the development process and ideas reasoning
begin from real life. From real life, there are concrete
examples physicaly about mathematics problems.
Mathematics in real life is not only in plain view but also can
be imagined.
By imagining mathematics problems, it can apply
mathematical logics concept. The concept in mathematics
should be learned to be able to know other concept in
mathematics. Mathematics is said real by Wardhani (2004:6)
can be applied in daily life. By the statement, mathematics is
also exact knowledge. To answer the problems need problems
solving by looking for the solution of the problems.
The evidence that mathematical concept can be applied in
real life is that there are problems which are connected to daily
life, Mathematics question have many kinds of choice. There
are mathematical questions in phenomenological questions in
order the students can be interested in the concept.
The student‟s approximation method Making the students to be more comfortable and
increasing the students passion to get knowledge is the main
duty of teacher. By approximation of students can be got an
effective class because the education in the class is harmonic.
Approximation of the students can be done personally by
implant the motivation and implant benefaction that must be
done. Devine and friends (in Baaiouny: 2008) told that the
teachers should explain what benefaction must be done in life
because benefaction is life values that must be understood.
The transition time has big influence in establishing the
character in 12th – 13th years old. The teenagers feel want to
know everything such us the information or the new things.
The teachers can benefate inquirin of the students in
establishing the character. Good character can make the
students to be high quality generation.
The relevant observation Raymond L. Calabrese (2002), in his research declared
that a leader must have good character in order the persons
who are leaded can followed him. The leader in the class is the
teachers who should have good character which can be
followed by the students. Ethical character can influence the
students very much.
Sri Wardhani (2004), in her research arranges the
contextual learning has the aim to benefete mathematical
concept in order can benefeted in daily life. Beside the
mathematical concept, the students who know mathematics
are hoped to get reasoning ability in students which can be
known by critical, logical, and systematic thinking and have
objective character and honest in solving the problems either
in mathematics or social field.
Progress
Basically, learning process in a communication process
which consist of information delivering as material learning
from the teachers by using a certain method so that the
students can accept, understand and apply mathematical
concept in daily life by the positive point of view.
The known mathematical concept which is the mother of
all knowledge makes easier to apply mathematical concept in
the real life by positive point of view. Pleasing learning and
developing the student passion to accept the mathematical
concepts is the unique way to apply in the real life.
The developing of mathematical concept in character
establishing process in daily life can be determiner to make
the students have good character as the studied mathematical
concepts.
Following the time development which is be better,
education become main determiner for someone will be
success or not, useful or not. Useful people will give
advantages for other people. Useful people is based on how
much the knowledge he has.
There are many education institution formed to increase
the education quality in Indonesia. But it is rare for the
teachers can be made a model. The real model is related to the
teaching process, relation and interaction as long as the
education process which will be the model of other people
nowadays or future. In a learning process, behaviour of the
teacher will become the effective communication and
influence very much (90%) to students (anonim:2010). For a
teacher, becoming a model is not a demand but the effect for
the students to become a model for the students.
Mathematics is an exact knowledge. Fathani (2009) said
that in mathematics there are many kind of system which is
formed by some axiom and theorems and in each system has
consistent character. Mathematics has a system which must be
obeyed and consistent. For example, 2+2=4, this statement
obtains in the daily life for good. This character is also applied
in the daily life, for example when someone choose a decision,
so he must be consistent with his decision. Beside that,
mathematical logics also the imagion of the real life. The
implication is applying promise concept, conditional, and
effects. If someone has been promised to anyone so he should
obey his promise. So that, the mathematical concept can be
used as the mediator of forming the character of the students
to become the model in the future.
According the education expert Prof. Dr. Budiono in the
national conference LSM XX (Budiono: 2012), to create a
success learning system, basicaly a learning system must make
the pleasing learning. There are many variation learning model
can be made as the effort to increase the achievement of the
students. The delivering way is pleasing and relax but not
The Third Basic Science International Conference - 2013 M16-3
decreasing the sense of the material is the delivering way
which is favorite for the students and very effective to apply in
the class.
The teaching system by combining the teacher‟s character
and mathematical concept which is applied for the students
can establish the student‟s character to be discipline,
visionary, responsible, consistent and honest. So the learning
is not only centered in the students but also applying everyone
is teacher system also the role of the teacher is very important
in giving example.
Conclusion Learning process which is offered in this paper is a
learning system which is not only support the achievement the
students but also can establish students character to be
discipline, visionary, responsible, consistent and honest.
Besides that, the students is hoped to be the good model for
their friends and become the wise leader in the future.
REFERENCES
[1] T. Amelia. (2012, January 14th). “ Optimasi peran parenting dalam
pengawasan penggunaan media internet demi membangun karakter
positif remaja.” In International Conference of Guidance and Conselling
Padang State University. [Online]. Available:
http://edukasi.kompasiana.com/2012/01/30/optimasi-
peran-parenting-dalam-pengawasan-penggunaan-media-
internet-demi-membangun-karakter-positif-remaja/. [2] Anonim. (2012, April 14th). “Menjadi guru Teladan yang Profesional
Sebagai Motivator kelas.” [Online]. Available:
http://semangatbelajar.com/menjadi-guru-teladan-yang-
profesional-sebagai-motivator-kelas/ #.
[3] Budiono, “Pembelajaran Matematika Yang Menyenangkan,” in Nation
Conference LSM XX Yogyakarta State University, 2012.
[4] Calabrese, Raymond L, and R.Roberts, Character, “School Leadership,
and The Brain: Learning How To Integrate Knowledge With Behavioral
Change,” The International Journal Of Education Management, 16, 4/5;
ProQuest Education Journals pg. 229, 2002.
[5] Crow and alice Crow, “Educational Psychology Lester 198,” PT Bina
Ilmu, Surabaya, 1984.
[6] Fathani and Andul Halim, “Matematika : Hakikat dan Logika,”
Yogyakarta, Ar-Ruzz Medi, 2009.
[7] N. Fatmawati. (2012, April 14th). “Pemanfaatan Internet Sekolah
Sebagai Sumber Belajar Alternatif Dalam Meningkatkan Hasil Belajar
Siswa Pada Mata Pelajaran TIK (Teknologi Informasi Dan
Komunikasi).” [Online]. 34th JHS of Surabaya. Available:
http://blog.elearning.unesa.ac.id/tag/kendala-membina-karakter.
[8] Indiati, Intan dan Listyaning Sumardiyani. (2012, April 14th).
Pengembangan Model Reflective Microteaching Untuk Pembentukan
Calon Guru Profesional. [Online]. Available:
http://jurnalaksioma.net/?p=166.
[9] Margunani, and Siti Fatimah. (2012, April 14th). “Keterampilan Guru
dalam Pengelolaan Kelas pada Mata Pelajaran Akuntansi di SMA
Negeri se Kabupaten Kebumen.” [Online]. Available:
journal.unnes.ac.id/index.php/DP/article/download/442/395.
[10] Ahmed Taher, Noha El-Bassiouny, and Ehab M. Abou-Aish, “The
Importance Of Character Education For Tweens As Consumers,” A
Conceptual Model With Prospects for Future Research, Journal of
Research in Character Education, Vol. 6, No. 2, 2008.
[11] S.Wardhani, “Pembelajaran Matematika Kontekstual di SMP”, Nation
Instructor Trainning/Mathematics Development on JHS Elementary
Degree, 2004.
The Third Basic Science International Conference - 2013 M17-1
Abstract— Pictures or other learning aids are frequently used
by teachers in elementary schools as media for teaching
mathematics, especially geometry. In line with the development of
technology, Augmented Reality (AR) technology can be used as
an alternative learning media for Geometry. The application of
AR technology for education has been discussed in many
literatures. This paper discusses the application of AR technology
for elementary education in order to increase the attractiveness
and motivation of the student in learning geometry. A book that
has been integrated to AR technology can present the geometric
objects in a virtual machine utilizing camera and computer. In
that geometry book there is a marker that can be identified as the
geometry object to be presented. The application will display the
geometry object in 3D on the screen. This presentation of
geometry object utilizing AR technology can be used as an
alternative learning media as well as to introduce the
implementation of AR technology for elementary education.
Keywords: Augmented Reality (AR), geometry, learning aids,
marker
I. INTRODUCTION
esearch on geometry learning tool in elementary schools
based on attractive, iconic, and a valid symbolic, practical
and effective way have shown to foster creative thinking
abilities learners in the subject matter of simple flat geometry
object[1]. Survey of the use of visual aids in teaching plane
geometry at the elementary school level have also been
conducted to determine how the use of the learning aids for
plane geometry at the elementary level[3]. The study shows
there are several difficulties of which are difficult to make the
necessary learning aids in flat geometry lesson, difficulty to
construct the learning concepts through aids, difficulty pushing
students to be more active or more involved physically,
difficulty pushing students more active / more emotionally
involved, difficulty involving the use of the five senses as
channels of information simultaneously (sight, hearing, smell,
and feelings), difficulty to encourage students involved in high-
level cognitive activities (problem solving, creative thinking,
creativity creating, innovating, etc.) developmentally
appropriate child psychology [3].
in line with the development of technology, Augmented Reality
(AR) has been used for various things including education.
Geometry education tool with AR technology for high school
and university education also been made in austria by using a
head mounted display equipment (fig. 1) . this system tool
provide a natural setting collaboration of teachers and students
(fig. 1) [2].
Fig 1. Collaboration class (right), Head Mount Display equipment (left)
This study tries to apply the AR technology in a simple way
as learning aids or media in teaching geometry for elementary
education especially about 3 dimensional objects. In this study,
the implementing of AR technology adapted to the device
available in most primary schools in Indonesia. This geometry
learning aids is not have to use the equipment such as head
mounted displays (HMD) to facilitate the use of these tools,
because there is no school that has the equipment, and the
equipment is still quite expensive to be provided in elementary
school level in Indonesia generally. For the easiest and simplest
solution in developing geometry learning aids customized with
AR technology, the implementation is made by a regular
computer and camera. The media of this tool is a geometry
handbook integrated with a symbol as the marker inside the
page.
II. MAGICBOOK CONCEPT
This learning aids use the physical book contained a marker
as a media for AR technology implementation named
magicbook. Magicbook interface on a several paper similar to
each other. In some papers the magicBook interface has two
components; a handheld one or more displays (HHD) or can be
a HMD and the physical book. The HHD is a handle with a
Sony Glasstron display mounted at the top, an InterTrax
InterSense inertial tracker at the bottom, a small camera on the
front of the Glasstron display and a switch and pressure pad
(fig. 3). The Sony Glasstron is a bioccular color display with
two LCD panels of 265x235 pixel resolution. The camera
output is connected to a desktop computer and the video-out
of the computer is connected back into the HHD. So by
looking through the HHD users experience a video-mediated
Object Representation on Geometry Learning
using Augmented Reality Approach
Nelly O. Adiwijaya
R
The Third Basic Science International Conference - 2013 M17-2
reality[5]. The books used in the MagicBook interface are
normal books with text and pictures on each page. Certain
pictures have thick black borders surrounding them as marker.
When the reader looks at these pictures through the HHD,
computer vision techniques are used to precisely calculate the
camera position and orientation relative to the picture. The
computer then generates virtual images that Appear precisely
registered with the real pages.
Fig 3. Magicbook with HHD
In this paper the concept of magicbook is not using the
HDD. Representation of virtual object using a personal
computer and a small camera connected or a built-in camera.
The physical book which user used within marker is the same
concept of another magicbook. The output images that appear
on the screen can be seen by all students. A user in this case a
teacher can show the 3D virtual objects by directing
magicbook before the camera. The computer vision techniques
are used to translate the marker into a 3D virtual object. The
virtual object on the screen can be seen by students directly or
through the projector in front of the class if any.
III. DETECTION MARKER AND CAMERA CALLIBRATION
The books used in the MagicBook interface are normal
books with text and pictures on each page. Certain pictures
have thick, black borders that are used as tracking marks for a
computer vision-based camera tracking system. When the
marker exposes the user in front of camera, computer vision
techniques precisely calculate the camera position and
orientation relative to the tracking mark. The camera tracking
uses the augmented reality tool kit (ARToolKit) tracking
library, an opensource software library for developing vision-
based augmented reality applications (see the ARToolKit Web
site) [6]. Once the computer calculates the camera position, it
generates virtual images that appear precisely registered with
the real pages.
IV. THE APPLICATION OF GEOMETRY LEARNING AIDS
Development of learning aids especially for geometry
education in line with development of technology at the
elementary level in Indonesia is one of the business
development field exploration of AR technology.
Implementation of AR technology here is tried in a simplest
way hopefully can be accepted by a school that only have a
regular desktop computer devices without any special tools to
visualize. This geometry magicbook learning aids use the
concept that has been developed previously. Magicbook
concept integrated into the regular geometry textbooks
(figure.4) used by students or teachers teaching geometry
lesson. Geometry handbook has been adapted to the
magicbook concept that contain the certain image as marker in
it. These markers are then to be translated by a computer with
a camera calibration method.
Fig. 4 Geometry textbook
The use of these applications can be performed in class or a
computer lab with a teacher guide. If the elementary school has
a computer in every classroom and equipped with a viewer, the
teacher can demonstrate to the students directly in the
classroom. Teachers as users simply point the camera to the
page with marker that has been linked to a computer with the
AR program to display the geometry virtual object. The
students then can see the results of the transformation marker
in the handbook becomes a virtual object on a computer screen
or projector screen. Figure 5 is an example of a geometry book
to be magicbook can display virtual objects.
Fig. 5 Magicbook display the 3D geometry virtual object
The result of this research can be an alternative simply
modern learning aids in geometry education for elementary
schools in the development country like indonesia. An AR
technology recognizing need the simpler way and familiar
device to be accepted. Many elementary schools in Indonesia
do not have a computer lab moreover the special device like
HDD or HMD to implement the AR technology. Using the
standard AR technology, ARToolkit is compatible for this
The Third Basic Science International Conference - 2013 M17-3
case. Through at least one computer machine, the schools can
use the AR learning aids and it maybe possible to do. This
implementation of the research hopefully can encourage the
students to learn the lesson in line with technology
development. And in addition this learning aids should
encourage students involved in high-level cognitive activities
(problem solving, creative thinking, creativity creating,
innovating, etc).
V. CONCLUSION
In line with the development technology especially in
Indonesia, the concept of AR technology can be simply
implemented in elementary school for geometry education. The
basic and standard implementation of AR technology can give
an alternative way representing a learning aids. This way can be
a non expensive tool but up to date and easy to be accepted by
the user. In addition this learning aids can encourage the
attractiveness and motivation of the student in learning
geometry.
For the next implementation, this concept can be
implemented in another lesson such as learning aids for
chemical education or biology, still in the simply way so the
user or schools in Indonesia easy to use this technology.
ACKNOWLEDGMENT
The author would like to thank prof. Slamin for the
discussion of educational mathematics.
REFERENCES
[1] Sugiarto, i. Junaedi, st. B. Waluya, “Pembelajaran Geometri Berbasis
Enaktif, Ikonik, Simbolik Untuk Menumbuhkan Kemampuan Berpikir
Kreatifpeserta Didik Sekolah Dasar”, journal of primary educational,
vol.1, no. 1, 2012
[2] H. kaufmann, M. Papp,” Learning Objects For Education With
Augmented Reality”, http://citeseerx.ist.psu.edu/viewdoc/download?doi=
10.1.1.100.2194&rep=rep1&type=pdf
[3] Siregar,R. Romayanti, “Survei Penggunaan Alat Peraga Dalam
Pembelajaran Geometri Bidang Datar Di Sd Kecamatan
Padangsidimpuan Utara T.A 2012/2013”, Fmipa Unimed, 2012
[4] H. Kaufmann, D. Schmalstieg,” Mathematics And Geometry Education
With Collaborative Augmented Reality”, Computers & Graphics, volume
27, issue 3, june 2003, pages 339–345
[5] M. Billinghurst, H. Kato, I.Poupyrev, “MagicBook: Transitioning
between Reality and Virtuality”, Computer Graphics and Applications,
IEEE, volume 21, issue 3, May/Jun 2001
[6] ARToolKit Documentation, http://www.hitl.washington.edu/artoolkit
/documentation/
The Third Basic Science International Conference - 2013
M18-1
A. B. Astuti, N. Iriawan, Irhamah and H. Kuswanto
1Abstract-Microarray is an analysis technique to monitor
gene expression activity simultaneously. In this case, gene
expression data is defined as the data of microarray
experiments. The problems that commonly arises from gene
expression data is limited availability of the number limited
budget, resources and time. Though the availability of the
number of samples is limited, the measurable characteristic
variables can be hundreds or even thousands of gene
expression. By these special characteristics, it is possible that
the nature of the distribution of gene expression data will be
very complex in which the distribution of the data obtained is
probably not a normal distribution. Various studies conducted
using frequentist approach apply t-student statistic, however
this approach requires strict compliance with the assumption
that the distribution of the data comes from a normal
distribution with a large enough sample size. Bayesian analysis
is an analysis that may answer this challenge where the data
analysis is driven by the nature of the data using posterior
probability distribution. The purpose of this study is to identify
the appropriate distribution of gene expression data as a result
of microarray experiments and to test hypotheses through
Bayesian confidence intervals using Highest Posterior Density
(HPD). The data used in this study is the gene expression data
of human colon tissue in healthy and diseased (infected tumor),
a data set that previously used in [1]. The results showed that
the distribution of gene expression data is asymmetry
(skewed/neo normal) and gene expression data in diseased
(infected tumor) and healthy conditions have different
distributions. Based on the overlapping distribution and
boundaries of HPD it is known that most of the data indicate
no difference gene expression in human intestinal tissue on
diseased (infected tumor) and healthy conditions. But the
exploration of the data indicated that the genes in a healthy
condition is more expressive than the diseased condition.
Manuscript received April 4, 2013. Highest Posterior Density for
Identifying Differences in Gene Expression Microarray Experiments.
A. B. Astuti is with the Mathematics Department of Mathematics and
Natural Sciences, Brawijaya University Jl. Veteran Malang 65145
Indonesia ; e-mail: [email protected]
N. Iriawan is with the Statistics Department of Mathematics and
Natural Sciences, Institut of Teknologi Sepuluh Nopember Surabaya,
Kampus ITS Sukolilo, Surabaya 60111 Indonesia; e-mail:
Irhamah is with the Statistics Department of Mathematics and Natural
Sciences, Institut of Teknologi Sepuluh Nopember Surabaya, Kampus ITS
Sukolilo, Surabaya 60111 Indonesia; e-mail: [email protected]
H. Kuswanto is with the Statistics Department of Mathematics and
Natural Sciences, Institut of Teknologi Sepuluh Nopember Surabaya,
Kampus ITS Sukolilo, Surabaya 60111 Indonesia; e-mail:
Keywords: Bayesian Interval Confidence, Differences in
Gen Expression, Highest Posterior Density, Microarray
Experiments
I. INTRODUCTION
Microarray is an analysis technique to monitor the
activity of thousands genes simultaneously, thus the gene
expression data is the data obtained from
microarray experiment [2]. The problems that commonly
arises from gene expression data is limited availability of the
number limited budget, resources and time. Though the
availability of the number of samples is limited, the
measurable characteristic variables can be hundreds or even
thousands of gene expression. By these special
characteristics, it is possible that the nature of the
distribution of gene expression data will be very complex in
which the distribution of the data is probably not a normal
distribution [3].
Bayesian analysis is a statistical analysis method that
does not consider the number of samples which make it
possible to be applied for which make it possible to be
applied for large or small amounts of data. Performance of
Bayesian analysis based on the distribution data. The
posterior probability distribution is obtained from the
multiplication of the prior distribution (based on past data
information) and the likelihood function (based on
observational data obtained). The parameters in the Bayesian
analysis model is treated as random variable in the model
parameter space [4]. The advantage of Bayesian analysis is
to provide inference from an unknown variable based on the
posterior distribution of the data. Moreover, the analysis also
allows for the combination of different prior distribution as
well as facilitates the iterative updating of new information
which thus overcome the problem of uncertainty and
complexity of the models in the data [5].
Various studies have been conducted to identify
differences in gene expression
as a result of a microarray experiment using the student's t-
test, among others [6]; [7]; [8]; [9]; [10]; [11]; [12]. While
[1] have proposed a Bayesian Mixture Model. The use of
student's t-test requires strict compliance with the
assumption that is the distribution of the data comes from a
normal distribution with large enough sample size. This
research uses Highest Posterior Density (HPD) methods and
the concept of overlapping distribution to identify
differences in gene expression in diseased and healthy
conditions.
Higest Posterior Density for Identifying Differences in
Gene Expression Microarray Experiments
The Third Basic Science International Conference - 2013
M18-2
II. REVIEW OF THEORY
A. Microarray Experiments and Microarray Data
Microarray Experiment is a technique of data
collection by using the platform (reference/guidelines/base)
that is the result of duplication of the original object
identifier [13]. The measurement results of the microarray
technique called microarray data [13]. There are several
different technologies for microarray techniques,
one example is the technology of Synthetic oligonucleotide
microarray [14]. Gene expression data is the data from
microarray experiments thus the
gene expression data have characteristics of microarray data.
Data obtained from experiments with microarray
technique has the following characteristics [15]: the basic
distribution of data has a complex shape, the number of
samples that can be observed very limited because of limited
funds, manpower, time and the availability of samples and
the characteristics of the variables that can be observed very
large. It can reach tens thousands of characteristics in each
experiment.
Based on the characteristics possessed by the
microarray data therefore it requires special treatment as the
usual parametric statistical method for comparison requires a
large enough sample size. If compliance with the number of
samples is violated then the conclusion of his analysis can
not be accounted for [16].
B. Bayesian Analysis
Bayesian analysis is a statistical analysis method based
on posterior probability distribution model which is a
combination of the two information is information of past
data as prior information and the observed (sample) is used
as a constituent likelihood function to update the prior
information [13], [17], [4]. The Rational of Bayesian
analysis derived from Bayes Theorem thinking concept
invented by Thomas Bayes in the year 1702-1761. In
Bayesian analysis, the parameters of the model is seen as
a random variable in the parameter space .
Suppose there are x observational data with likelihood
function
)|( xf then the known information about the
parameters before the observations were made is referred
to as prior namely )(p . Furthermore, to determine the
posterior probability distribution of , namely )|( xp
based on the rules of probability in Bayes Theorem [18] as
follows:
)(
)()|()|(
xf
pxfxp
where
(2.1)
)]|([)( xfExf = Rx
dfxf )()|( if
continuous and
)]|([)( xfExf =Bx
pxf )()|( if discrete.
)(xf is a constant called the normalized constant [4]. The
equation (2.1) can be written as:
)()|()|( pxfxp
(2.2)
Posterior Likelihood Function x Prior
According to equation (2.2) it is known that the posterior
probability proportional the product of the likelihood
function and the prior probability of the model parameters.
This means that the update's information prior to use the
information in the likelihood of data sampling to obtain
posterior information that will be used for decision making.
C. The Concept of Confidence Interval of Highest
Posterior Density (HPD)
C.1. The Concept of Equilibrium in the Density
Distribution of Symmetry
The basic concept of the formation of the confidence
interval on the data distributed symmetry (normal
distribution) are as
follows:
1)//( 2/2/ nsZxnsZxP (2.3)
According to equation (2.3) can be seen that
)()( BxPBxP with )/( 2/ nsZB . This
means that the jump with the length of B the right side x
will have a value of density of )( BxP the same height
as the density when it jump to left side of with the length of
B x , as high as
)( BxP [15].
On the symmetrical distribution (normal distribution),
the location of the mean, median and mode lies in the same
location so that the equation (2.3) at the boundary control
points will automatically have the equilibrium value of the
density. This means the moverment to the left and to the
right of the data center by a given standard deviation has the
same density values or equilibrium. This concept is referred
to as the concept of equilibrium density or the Highest
Posterior Density (HPD) [15]. C.2. The Concept of Equilibrium in the Density
Distribution of Asymmetry (Skewed/Neo Normal)
The basic concept of the formation of the confidence
interval on the data is asymmetrical distributed (skewed/ neo
normal) can-not use the concept of the equation (2.3) due to
the location of the mean, median and mode which lies in a
different location. In this case, the concept of HPD uses
location as a reference mode of data center. At HPD concept
for data distributed skewed, the limits to the distance jumps
to the left and right are different lengths but will have the
same high density values [15].
The algorithm of formation equilibrium density
(HPD) for asymmetrical distributed data (skewed/neo
normal) is as follows [15]:
(1). Determine the mode of the density is not symmetry
(skewed)
(2). Put your data center in this mode
The Third Basic Science International Conference - 2013
M18-3
(3). Create jump steps to the left and to the right of the mode
to determine the lower limit of the interval,
ax (LCL=Lower Control Level)) and the upper limit
bx (UCL=Upper Control Level)) to keep control of
the equilibrium density, )()( bxfaxf to
obtain the probability interval for 1 or
1)()(
b
a
dxxfUCLxLCLP
III. METHODOLOGY
A. Data
The data used in this study is the one used in [1] i.e.
the gene expression data of human colon tissue in diseased
(infected tumor) and healthy (uninfected tumor) conditions
in which the method of detection of gene expression that
there are 2 methods of Poly Detector and mRNA. The
Number of samples used in the study is 11 patients with
diseased conditions in which gene expression was observed
with Poly Detector method, 10 patients healthy conditions in
which gene expression was observed with Poly Detector
method, 29 patients diseased conditions in which gene
expression was observed by the method of mRNA and 12
healthy patients in which gene expression was observed by
the method of mRNA.
B. Methods
1. Identify the most appropriate distribution as well as
estimates the parameters for gene expression data of 11
patients at the diseased condition in which gene
expression was observed with Poly Detector method.
2. Identify the most appropriate distribution as well as
estimates of parameters for gene expression data of 10
patients at the healthy condition in which gene
expression was observed with Poly Detector method
3. Identification of overlapping distribution based on the
results of identification steps (1) and (2). 4. Determine the limits of HPD based on the results of step
(3)
5. Repeat steps (1) through (4) for gene expression data 29
diseased patients where gene expression was observed by
the method of mRNA and 12 healthy patients in which
gene expression was observed by the method of mRNA. Data analysis using statistical software Minitab 16, EasyFit
5.2 and Maple 5 R-4.
IV. RESULTS
A. Identify the Distribution and Parameter Estimators
for Gene Expression Data Diseased and Healthy
Conditions
The results of the identification of the data distribution
and parameter estimators for gene expression in diseased and
healthy conditions using 2 methods applied show that there
is a difference in term of the distributions between diseased
and healthy conditions. It is also known that most of the data
has asymmetric distribution (skewed/neo-normal). Based on
the results of data exploration it is known that most of the
data indicate that gene expression in healthy condition is
more expressive than the diseased condition. For instance
the distribution of data on diseased condition (black line)
and healthy (dashed red line) with Poly Detector method on
gene ID H55933 follows:
2500020000150001000050000
0.00018
0.00016
0.00014
0.00012
0.00010
0.00008
0.00006
0.00004
0.00002
0.00000
X
De
nsit
y
Lognormal 8.4 0.66 1145.2
Distribution Loc Scale Thresh
Weibull 1.44 5699.81 3469.12
Distribution Shape Scale Thresh
Distribution Plot
Fig. 4.1. Distribution Data on Diseased Condition
(Lognormal (3P)) and Healthy Condition (Weibull (3P))
with Poly Detector Method on Gene ID H55933.
B. Identification of Overlapping Distribution and Limits
of HPD on Gene Expression Data Diseased and
Healthy Conditions on ID 10 Genes with Average
Value Largest Gene Expression.
The results of the overlapping distribution and
boundaries HPD data on diseased and healthy conditions are
listed as follows:
Table 4.1.
Overlapping Distribution and HPD Boundaries of 10 Genes
with Average Largest Gene Expression.
No Genes
ID
Overlaping Distribution and
HPD Boundaries
Diseased-PL vs
Healthy-PL
Diseased-mRNA vs
Healthy-mRNA
1 H55933 Overlapping Overlapping
2 T52342 Overlapping Overlapping
3 J02763 Overlapping Overlapping
4 R02593 Overlapping Overlapping
5 T95018 Overlapping Overlapping
6 H20709 Overlapping Overlapping
7 T65938 Overlapping Overlapping
8 T65938 Overlapping Overlapping
9 R22197 Overlapping Overlapping
The Third Basic Science International Conference - 2013
M18-4
10 X63432 Overlapping Overlapping
Based on Table 4.1. it is known that all ID genes have a
distribution and HPD boundaries overlapping between
diseased and healthy conditions. This means that the
statistical test revealed no differences in gene expression
between human colon tissue in diseased (infected tumor) and
healthy (uninfected tumor) conditions.
V. CONCLUSION
Based on the results of research it can be concluded
that the gene expression data as a result of a microarray
experiment has the form asymmetrical (skewed/neo-normal)
distribution in both diseased and healthy conditions.
Moreover, this type of distribution is also different in the
two conditions. There are overlapping distributions and HPD
boundaries of gene expression data on the diseased condition
(infected tumor) and healthy condition (uninfected tumor)
suggests that there is no difference of gene expression in
human colon tissue between the diseased condition (infected
tumor) and healthy condition (uninfected tumor). But the
results of data exploration is known that most of the data
indicate that gene expression in healthy condition is more
expressive than the diseased condition
REFERENCES
[1] K. A. Do, P. Muller and F. Tang, “A Bayesian Mixture
Model For Differential Gene Expression”,
Research in Department of Biostatistics, The
University of Texas, 2004. [2] S. Knudsen, “A Guide to Analysis of DNA Microarray
Data”, Second Edition,. John Wiley & Sons,
Inc., New Jersey, Canada, 2004
[3] P. Muller, G. Parmigiani, C. Robert and J. Rouseau,
“Optimal Sample Size for Multiple Testing: the
Case of Gene Expression Microarrays”, Tech.
rep., University of Texas, M.D. Anderson
Cancer Center, 2002.
[4] A. Gelman, J. B. Carlin, H. S. Stern and D. B. Rubin,
“Bayesian Data Analysis”, Chapman & Hall,
London, 1995.
[5] K. Mengersen, “Modul 1 Bayesian Analysis. Short
Course on Bayesian Modeling”, Statistics
Department, ITS, Surabaya, 2009.
[6] N. Harijati, “A Study of the Resistance of Chickpea
(Cicer Arietinum) to Ascochyta Rabiei and the
Effect of Age of Plant Tissue on Disease
Development”, Ph.D, Thesis, La Trobe
University, Australia, 2007. [7] M. Schena, D. Shalon, R. W. Davis and P. O. Brown,
“Quantitative Monitoring of Gene Expression
Patterns with a Complementary DNA
Microarray”, Science. 270, 1995, pp. 467–470.
[8] M. Schena, D. Shalon, R. Heller, A. Chai, P. O. Brown,
and R. W. Davis, “Parallel human genome
analysis: Microarray-based expression
monitoring of 1000 genes”, Proceedings of the
National Academy of Sciences, 93, 1996, pp.
10614–10619.
[9] J. L. DeRisi, L. Penland, P. O. Brown, M. L. Bittner, P.
S. Meltzer, M. Ray, Y. Chen, Y. A. Su and J.
M. Trent, “Use of a cDNA Microarray to
Analyze Gene Expression Patterns in Human
Cancer”, Nature Genetics. 14, 1996, pp. 457–
460. [10] P. Baldi and A. D. Long, “A Bayesian Framework for
the Analysis of Microarray Expression Data:
Regularized T-Test dan Statistical Inferences
of Gene Changes”, Bioinformatics, 17, 2001,
pp. 509-519.
[11] I. Lonnstedt and T. P. Speed, “Replicated Microarray
Data”, Statistica Sinica, 12, 2002, pp. 31–46.
[12] V. G. R. T. Tusher and G. C, “Significance Analysis of
Microarrays Applied to the Ionizing Radiation
Response”, In Proceedings of the National
Academy of Sciences, Vol. 98, 2002, pp. 5116–
5121.
[13] G. E. P. Box and Tiao, “Bayesian Inference in
Statistical Analysis”, MA: Addison-Wesley,
Massachusetts, 1973. [14] J. D. Duggan, M. Bittner, Y. Chen, P. Meltzer and J. M.
Trent, “Expression Profiling Using CDNA
Microarrays”, Nature Genetics, 21, 1999, pp.
10-14.
[15] N. Iriawan, “Modeling and Analysis of Data-Driven (in
Indonesia)”, Volume I. ITS Press, Surabaya,
2012.
[16] P. Sebastiani, H. Xie and M. F. Ramoni, “Bayesian
Analysis Of Comparative Microarray
Experiments By Model Averiging”,
International Society For Bayesian Analysis, 1,
number 4, 2006, pp. 707-732.
[17] A. Zellner,”An Introduction to Bayesian Inference in
Econometrics”, John Wiley, New York, 1971.
[18] J. K. Gosh, M. Delampady dan T. Samanta, “An
Introduction to Bayesian Analysis Theory and
Methods”, Springer, New York, 2006.
The Third Basic Science International Conference - 2013
M21-1
Abstract— The measurement error is an error that appears when
the value of the note is not exactly the same as the true value in
relation to a measurement process, so that the true values of the
explanatory variables is represented by a value obtained through
a process of measurement that are not necessarily in accordance
with the true value. The presence of measurement error causes
biased and inconsistent parameter estimates and leads to
erroneous conclusions. The measurement error models can be
used to resolve these problems. This paper will discuss the
estimation of parameters under the assumption that the variance
of the measurement error , is known. We use data on cases
of malnutrition in the province of East Java to illustrate the
estimation of the parameters of this model.
Index Terms— measurement error models, method of least
squares, malnutrition
I. INTRODUCTION
here are two forms of linear regression models. The first
form is the classical linear regression model that assumes
variables X is considered fixed and the errors are
independent random variables distributed ). The
second form is a regression model where X is assumed to be
freely obtained from the diffuse X population distributed
and vectors ) are independent with
the vectors ) . In both models, the estimates of
β is the maximum likelihood estimator unbiased for β [1].
However, sometimes the actual data do not meet the
assumptions used in the two forms of regression. If the
explanatory variable X can’t be observed directly or can’t be
measured precisely (measured without error) then there will be
problems of measurement error. The presence of measurement
error because parameter estimators biased and inconsistent and
lead to incorrect inferences [2]. To overcome these problems
we used a measurement error models.
The difference between linear regression models with
measurement error models lies in the independent variables. In
measurement error models, independent variables are
unknown or random variables that have a particular
distribution, while the linear regression independent variables
are considered fixed or do not have a particular distribution.
I.M. Hutabarat is Lecturer at Department of Mathematics, Cenderawasih
University (Uncen), Indonesia (phone: 08114800899; e-mail:
A. Saefuddin is now with the Department of Statistics, Bogor Agricultural
University (IPB), Indonesia (e-mail: [email protected]).
Hardinsyah is with Department of Community Nutrition, Bogor
Agricultural University (IPB), Indonesia, (e-mail:
Djuraidah is with the Department of Statistics, Bogor Agricultural
University (IPB), Indonesia (e-mail: [email protected]).
The difference between the two models are also shown in the
parameter estimation and the use of assumptions.
II. LINEAR REGRESSION MODEL WITH
MEASUREMENT ERROR
A. Model
Measurement error can be caused by various factors. In
general, measurement error divided into two types: random
error and systematic error. Random error is caused by any
factors that randomly affect measurement of the variable
across the sample. Systematic error is caused by any factors
that systematically affect measurement of the variable across
the sample [3].
In matrix notation, regression equation with measurement
error can be written:
(1)
In model (1) shows that measurement error models have a
similar form with the conventional regression model.
The assumption model of measurement error is:
(2)
where, ~ NI means "normal distribution and independent" and
is a diagonal matrix with diagonal elements given in the
matrix, as well as the assumed known.
By the least squares method assuming that the variance of the
measurement error ( ) is known, then estimation regression
coefficient is as follows:
where
B. Estimation of true X values
Based on the knowledge of the parameter about the
structural relationship and an observation (Yi,Zi), it is possible
to construct an estimator of Xi superior to Zi. In constructing
an estimator of Xi, the unknown Xi, can be treated as fixed or
random, and the two assumptions lead to different procedures.
Estimation for each of the assumptions of the Xi.
a. if Xi fixed
(3)
Estimation in Measurement Error Models on Cases of
Malnutrition in the Province of East Java
Ida Mariati Hutabarat1,2
, Asep Saefuddin2, Hardinsyah
3, Anik Djuraidah
2
T
The Third Basic Science International Conference - 2013
M21-2
where is covariance matrix
and .
b. if Xi random
Treating Xi, as random and replacing parameters with
estimators, the predictor of Xi, , is
where
, and
Having obtained the true X values, then to test the effect of
the true X values to variable Y, then the hypothesis is the
same as the conventional regression model.
III. APPLICATION OF THE CASE MALNUTRITION
DATA
In this paper, the model regression applied in cases of
toddler malnutrition in the East Java Province in 2010.
Variables such that is the percentage of toddler malnutrition as
variables response (Y) and the percentage of households have
access to clean water (X1), the percentage of poor people (X2),
the percentage infants contracting from infectious diseases
(X3), the percentage of income spent monthly for food (X4),
the percentage of the posyandu (integrated service point)
(X5), the percentage of infants receiving exclusive breast-
feeding (X6). The data used in this research are secondary data
that have been collected by Statistics Indonesia (BPS) namely
the National Socio-Economic Survey (Susenas) data and
basic health research (2010) at 38 district in East Java
Province.
From the six explanatory variables, there is only one that
significantly influence to the response variables at α = 5%.
The variables that significantly influence infant malnutrition in
the province of East Java in 2010, is the percentage of the poor
(X2). So the only variable percentage of poor (X2) which I
use in the analysis to create a regression model with
measurement errors for the percentage of severely
malnourished children under five in the province of East Java
in 2010. Estimated percentage of poor population contains
measurement error arise from two sources. First, instrumental
error such as questionnaire instrument which has not
accommodate the poor people category. Second, personal
errors associated with the analysis used to determine the
household (family) poor.
If the assumed variance of the measurement error arising
from these two sources is estimated , then the
regression model with measurement error that are formed are
as follows:
The model explains that the toddler malnutrition Will
increase 0.198 percent if the variables of poor households
(X2) increased by one percent on the condition that the other
variables are constant.
The assumption of residual that normal distribution is met,
we can estimate the value the assumed fixed, namely:
TABLE I
PARAMETER ESTIMATION OF REGRESSION MODEL WITH
MEASUREMENT ERROR
Parameter estimate SE coef T p-value
0.8289
0.0404
1.06
4.91
0.297
0.000**
Based on the analysis of partial parameter and analysis of
variance shown in Table 1 using a significance level of 1%, it
can be concluded that the percentage of poor households affect
the percentage of the toddler malnutrition. The coefficient of
determination (R2) generated by 40.1%, which means that the
regression model with measurement error can explain the
variability of the percentage of the toddler malnutrition at
40.1%, while the rest (ie 59.9%) is explained by other
variables outside of the model.
TABLE II
ANALYSIS OF VARIANCE REGRESSION MODELS WITH
MEASUREMENT ERROR
Source DF SS MS F p-value
Regression 1 133.71 133.71 24.09 0.000**
Residual error 36 199.85 5.55
Total 37 333.563
Test results obtained residual normality KS value of 0.129 and
p-value 0.111. By using α by 1 percent, then reject H0
otherwise fail, which means that the residual meet the
assumptions of normal distributed.
IV. CONCLUSION
Estimation in regression models with measurement error is
.
In cases of the toddler malnutrition as the response variable Y
with covariates Percentage of Poor People (X2) obtained
REFERENCES
[1] W.A. Fuller, Measurement Error Models. New York:
John Wiley & Sons, 1987.
[2] X. Chen, H. Hong, and D. Nekipelov. Nonlinear Models
of Measurement Errors. Journal of Economic Literature
2011, 49:4, 901–937, 2011
[3] Anonim. Measurement Error. http://socialresearch
methods.net/kb/measerr.php, diunduh pada Mei 2012.
The Third Basic Science International Conference - 2013 M22-1
Abstract— Consider the data are pairs ( , )j jt y , where the
relationship between predictor variables jt and response
variable j
y is assumed to follow heteroscedastic nonparametric
regression models ( ) , j j j jy f t where 1,2, ,j n . The
regression curve shape f is unknown and assumed to be smooth,
and contained in the space of [0, ]C as continuous functions.
j are independent random errors with zero mean and one
variance. Regression curve f is approximated by non-trend
Fourier series 0
1
1( ) cos
2
K
k
k
f t a a kt
. Estimation of
heteroscedastic nonparametric regression curves obtained from
solving optimization Weighted Penalized Least Square (WPLS):
1 2
(0, )0
2( ( )) ( ( )) [ ( )]
f CMin n y f t W y f t f t dt
.
Solution of the above optimization WPLS is Weighted Non-
Trend Fourier Series estimator, which can be presented in the
form of ˆ ( ) ( )f t H y , for a matrix ( )H that depends on the
bandwidth parameters . The properties of the Weighted Non-
Trend Fourier Series estimator in heteroscedastic nonparametric
regression is a biased estimator for the regression curve, and it is
in the class of linear estimators under observation. Beside that if
random errors have normally distribution in the regression
model then Weighted Non-Trend Fourier Series estimator in
nonparametric regression heteroscedastic also normally
distribution.
Keywords : Heteroscedastic Nonparametric Regression, Non-Trend
Fourier Series, Parameter Bandwidth, WPLS
I. INTRODUCTION
Regression analysis can be used to estimate the pattern of
relationships between predictor variables jt and the response
variable j
y . Consider the data are pairs ( , )j jt y with the
I Nyoman Budiantara is a lecturer at Departement of Statistics, Faculty of
Mathematics & Natural Sciences Institut Teknologi Sepuluh Nopember,
Surabaya, Indonesia phone: 081553527408, e-mail:
Rahmawati Pane is a student at Departement of Statistics, Faculty of
Mathematics & Natural Sciences Institut Teknologi Sepuluh Nopember,
Surabaya, Indonesia. e-mail: [email protected].
regression model ( ) , j j j jy f t where 1,2, ,j n .
The function f is the regression curve and j
random errors
are assumed independent normally distributed with zero mean
and 2 variance. When regression curve shape in regression
analysis is known then the regression is called a parametric
regression [4], [5], whereas when the pattern of data follow
the linear/quadratic/cubic model then the regression approach
that suitable for the data are linear/quadratic/cubic parametric
regression [6].
In real life, the real shape pattern of the relationship
between predictor variables jt and the response variable
jy
is unknown. In such cases, if parametric regression model is
forced to model the pattern of data then it will give a
misleading conclusion. Nonparametric regression is a
regression approach which is appropriate for the data pattern
of the unknown form of the regression curve or for no
complete information about the past shape of the data pattern
[7], [10]. Nonparametric regression models that get much
interest are Fourier series [8], [1] and [3], Kernel [8], [11] and
[6], Spline [2], [10] and Wavelets [1]. Nonparametric
regression approach has a high flexibility, since the data is
expected to find its own shape curve estimation regression
without influenced by the subjectivity of the researcher.
Among the nonparametric regression models mentioned
above, the Fourier series is a model that has very special and
good statistical and visual interpretations [8]. Fourier series
estimator is obtained from an optimization of Penalized Least
Square (PLS) [3]. Besides that Fourier series estimator is able
to handle character data/ functions that are smooth and follow
the periodic/recurrent/seasonal pattern at specific intervals [3].
Bilodeau [3] has developed a nonparametric regression
Fourier series to handle data pattern which is seasonal and
have the up-trend or down-trend and homoscedastic. The
pattern of up-trend or down-trend is shown by adding a linear
equation term in the Forier series models. Trend Fourier series
estimator developed by [3] and [8] is generally very suitable
for data pattern which is not only seasonal but also have the
up-trend or down-trend and homoscedastic. Problems will
arise in the use of Fourier series estimator if data pattern
seasonal but does not also have the up-trend or down-trend
and heteroscedastic. Therefore, it is necessary to develop a
Fourier series estimator which does not contain elements
either up-trend or down-trend and heteroskedastic.
In this study, a non-trend Fourier series estimator is derived
to estimate the heteroscedastic nonparametric regression
curves including its problem related to the estimator derived.
Non-Trend Fourier Series Estimator in Heteroscedastic
Nonparametric Regression
I Nyoman Budiantara and Rahmawati Pane
The Third Basic Science International Conference - 2013 M22-2
According to [3], this non-trend Fourier series estimator is
able to solve the weaknesses of the trend Fourier series
estimator in nonparametric regression. Non-trend Fourier
series estimator proposed in this study is expected to have
several advantages including (a) able to handle data with non-
trend periodic/seasonal patterns in nonparametric regression,
(b) able to solve nonparametric regression Fourier series
problems for the heteroscedastic cases.
II. NON-TREND FOURIER SERIES ESTIMATOR IN
HETEROSCEDASTIC NONPARAMETRIC REGRESSION
Consider the data are pairs ( , )j jt y , the relationship
between predictor variables jt and the response variable
jy is
assumed to follow heteroscedastic nonparametric regression
model:
( ) , 1, 2, ... ,j j j jy f t j n (1)
Regression curve shape is unknown and assumed to be
smooth, and contained in the space of [0, ]C as continuous
functions with:
[0, ] ; of continuous functions on the interval 0,C g g
j are independent random errors with zero mean and one
variance. Heteroscedastic regression curve f is approached
by non-trend Fourier series:
0
1
1( ) cos
2
K
k
k
f t a a kt
. (2)
Estimation of heteroscedastic nonparametric regression curves
f is obtained by solving optimization of the Penalized
Weighted Least Square (WPLS):
1 2
(0, )0
2( ) ( ) [ ( )]
f CMin n y f W y f f t dt
(3)
with the weight matrix 1
2 2 2
1 2diag ( , ,..., )nW
. Vector
1 2, ,...,T
ny y y y and f have the size (nx1). is
bandwidth parameter. To solve the optimization of (3) is done
by solving Goodness of fit:
1( ) ( ) 'G G f n y f W y f
and penalty:
2
0
2( ) ( ) [ ]P P f f t dt
By substituting ( 1)10 1 22
( , , ,..., ) KK . First
solved Goodness of fit. Heteroscedastic nonparametric
regression model in equation (1) can be written in the form of: 1/2( )y B t W ,
with:
1 1
2 2
1 cos cos
1 cos cos( )
1 cos cosn n
t Kt
t KtB t
t Kt
and 1
1/2 2 2 2
1 2diag ( , ,..., )nW
.
Goodness of fit in equation (3) can be stated as:
1( ) ( ) ( )G n y B t W y B t (4)
Since 0
1
1( ) cos
2
K
k
k
f t a a kt
, then the integral:
222
0210 0
2 2 1( ) cos .
2
K
k
k
df t dt kt dt
dt
By doing a bit of elaboration, the equation can be written
as:
2
4 2
10
2( ) .
k
k
k
f t dt k
.
.
The result is obtained:
42
04
0 0 0
0 1 02( )
0 0
f t dt
K
(5)
,D
the matrix 4 4 4(0,1 ,2 ,..., )D diag K .
When Goodness of fit in (4) and Penalty in (5) are combined
then the optimization of WPLS in (3) can be expressed as:
( 1)
( ) ( )K
Min G P
1 ( ) ' ( )( !)Min n y B t W y B t DK
(6)
If a little elaboration in the optimization (6) is carried out
then use partial derivatives to solve the optimization, finally
the normal equation is obtained:
1 12 ( ) 2 ( ) ( ) 0.n B t Wy n B t WB t D
Estimator for is given by:
1
1 1ˆ ( ) ( ) ( )n B t WB t D n B t W y
.
Non-trend Fourier series estimator to estimate the
heteroscedastic nonparametric regression curve is given by the
following equation:
ˆ ˆ( ) ( )f t B t (7)
11 1( ) ( ) ( ) ( )B t n B t WB t D n B t W y
The Third Basic Science International Conference - 2013 M22-3
( )H y
with 1
1 1( ) ( ) ( ) ( ) ( ) .H B t n B t WB t D n B t W
III. PROPERTIES OF NON-TREND FOURIER SERIES ESTIMATOR
IN HETEROSCEDASTIC NONPARAMETRIC REGRESSION
The following presents some important basic properties of
non-trend Fourier series estimator (7). First, the nature of the
Fourier series estimator in heteroscedastic nonparametric
regression is in linear estimator class in the observations
because it can be expressed as a linear combination of
observation (response). Non-trend Fourier series estimator of
(7) in the heteroscedastic nonparametric regression estimator
is a bias estimator for the regression curve f because:
ˆ ( ) ( ) ( ) [ ]E f t E H y H E y
= ( )H f f
Another property of non-trends Fourier series estimator in
heteroscedastic nonparametric regression is if the random
error in nonparametric regression models is normally
distributed then the estimator also normally distributed.
Assume that the random error:
1
20,
n
N W
Non-trend Estimator Fourier series (7) is also normally
distributed with mean given by:
ˆ ( ) ( ) ,E f t H f
and variance-covariance matrix is given by:
ˆ ( ) ( ) ( ) ( ) ( )Var f t H Var H H WH .
The next properties of non-trends Fourier series estimator in
heteroscedastic nonparametric regression is the estimator
highly depend on the bandwidth parameters and the value
of K. The best non-trends Fourier series estimator relates to
the optimal values of and K. Generalized Cross Validation
(GCV) method can be used to obtain the optimal values of
and K.
IV. CONCLUSION
Suppose the heteroscedastic nonparametric regression
models is ( )j j j jy f t for 1, 2, ...,j n
The shape of regression curve f is unknown and assumed to
be smooth, which means contained in the space of continuous
functions [0, ]C . The random errors j are independent
with zero mean and one Variance. The regression curves ( )f t
are approached by a non-trend Fourier series. The estimation
of heteroscedastic nonparametric regression curves is obtained
by solving the WPLS optimization:
1 2
(0, )0
2( ) ( ) [ ( )]
f CMin n y f W y f f t dt
a. The result of solution of WPLS optimization is the non-
trend Fourier series estimator, which can be presented in
the form of
ˆ ( ) ( )f t H y
for a matrix ( )H that depends on the bandwidth
parameter .
b. Non-trend Fourier series estimator in heteroscedastic
nonparametric regression is biased estimator for a
regression curve but it is in the in linear estimator class in
the observations.
c. Non-trend Fourier series estimator in heteroscedastic
nonparametric regression will normally distributed if the
random error in nonparametric regression models is
normally distributed.
d. The best non-trend Fourier series estimator in
heteroscedastic nonparametric regression is highly depend
on the optimal values of and K which can be obtained
using the GCV method.
REFERENCES
[1] A. Antoniadis, J. Bigot, and T. Spatinas, ”Wavelet estimators in
Nonparametric Regression: A Comparative Simulation Study”,
Journal of Statistical Software, vol. 6,
pp.1-83, 2001
[2] H. Becher, G. Kauermann, P. Khomski, and B. Kouyate, “Using
Penalized Splines to Model Age and Season of Birth Dependent
Effects of Childhood Mortality Risk Fabtors in Rural Burkina Faso”,
Biometrical Journal,vol.51, pp. 110-122, 2009
[3] M. Bilodeau, “Fourier Smoother and Additive Models”, The Canadian
Journal of Statistics,vol. 3, pp. 257-269, 1992.
[4] I. N. Budiantara, “Spline Model with Optimal Knots”, Journal of Basic
Science, State University of Jember, vol. 7, pp. 77-85, 2006.
[5] I. N. Budiantara, Statistical Inference for Spline Model”, Journal of
Mat-Stat, vol. 7, pp. 1-14, 2007.
[6] M. Y. Cheng, R. L. Paige, S. Sun, and K, Yan, “Variance Reduction for
Kernel Estimatiors in Clustered / Longitudinal Data Analysis”, Journal
of Statistical Planning and Inference, vol.140, pp. 1389-1397, 2010.
[7] M. Kayri, and G. Zirhhoglu, “Kernel Smoothing Function and Choosing
Bandwitdh for Nonparametric Regression Methods”, Ozean Journal
of Applied Sciences, vol. 2, 49-60, 2009.
[8] A. Tripena, and I. N. Budiantara, “Fourier estimator in
Nonparametric Regression”, International Conference On Natural
Sciences and Applied Natural Scienes, Ahmad Dahlan University,
Yogyakarta, 2007.
[9] N. Wang, “Marginal Nonparametric Kernel Regession Accounting for
whitin-Subject Correlation”, Biometrika, vol. 90, pp. 43-52, 2003.
[10] S. N. Wood, “On Confidence Intervals for Generalized Additive
Models Based on Penalized Spline Regression”, Aus. N. Z. J. Stat.,
vol. 48, pp. 445-464. 2006.
[11] C. O. Wu, and C. T. Chiang, ” Kernel smoothing on varying
coeficient with Longitudinal Dependent Variable Models”, Statistica
Sinica, vol.10, pp. 433-456, 2000.
The Third Basic Science International Conference - 2013 M23-1
Abstract—Unlike it counterpart in parametric regression
modeling, the development of nonparametric regression for count
response are moving slowly. In this research we developed a new
nonparametric regression approach for modeling count response
using local polynomial smoothing. By assuming generalized
Poisson distribution for count response, this model should robust
for over dispersion problem that often occurred in count data
modeling. Using maximum likelihood method for finding the
estimator, we called it as local (maximum) likelihood estimator. In
this paper we construct a confidence band of the unknown
regression function, which is difficult to build in nonparametric
regression context. The construction of the confidence band needs
estimated bias and variance of local likelihood estimator that we
have been derived earlier. We conducted some simulation to show
the behavior of the estimator as well as the confidence band.
Index Terms—generalized Poisson distribution, local
polynomial smoothing, local likelihood, nonparametric regression,
confidence band
I. INTRODUCTION
n the context of parametric regression analysis, Poisson
regression is a standard and baseline model for describing the
relationship between count response with some covariates.
Following its name, count response is assumed to follow the
Poisson distribution which have restricted properties called
equi-dispersion (i.e. mean should be equal to variance). This
situation is hard to fulfill by observational data, and often the
opposite situation where the observed variance exceeds the
observed mean, called over-dispersion, is occurred. Fitting
such data using Poisson regression model will seriously under
estimated the variance and can lead to misleading conclusion in
the inference [1]. As an alternative, there are others model
such as: Negative Binomial regression model [2], Poisson Log
Normal (PLN) model and Poisson Inverse Gaussian (PIG)
model [3] and also Generalized Poisson regression model [4].
The last model is preferred because not only more general than
Poisson regression (i.e. in special case it reduces to Poisson
Regression), but it is simpler comparing to others
In many cases, the relationship between response and
covariates cannot describe by simply fitting some parametric
1 PhD student at Department of Statistics, Institut Teknologi Sepuluh,
Surabaya, Indonesia and lecturer at Sekolah Tinggi Ilmu Statistik, Jakarta
Indonesia, e-mail: [email protected] 2,3 Lecturer at Department of Statistics, Institut Teknologi Sepuluh, Surabaya,
Indonesia , e-mail: [email protected] ,
sonny_s@ statistika.its.ac.id 4Lecturer at Department of Applied Statistics, Sekolah Tinggi Ilmu Statistik,
Jakarta, Indonesia , e-mail:[email protected]
function such as linear, exponential or polynomial function. In
such case, nonparametric regression seems to be a reliable and
reasonable choice. The aim of nonparametric regression is to
minimize the assumption about regression function and let the
data seeking for the function itself [hardle]. In nonparametric
regression, scatter plot smoothing is the simplest method to
estimate regression function. There are several approaches for
determined the regression function, such as kernel, spine and
local polynomial technique. These techniques known as local
fitting methods because the estimation of regression function is
done locally around some interval of points.
Unlike it counterpart in parametric regression model, the
development of nonparametric regression for count response
with local fitting is moving slowly. There is not much research
in this area, except [5], [6]. Local likelihood is a concept
introduced by [7] and developed more intensively by [8]. This
method extends the nonparametric regression analysis to
maximum likelihood based regression model which also known
as likelihood-based smoother. In this model, the mean of
response variables are assumed depends on covariates with
some nonlinear link function. Although, there are no presumed
function for the regression curve itself.
In this research we develop a nonparametric regression model
for count response using local polynomial approach for the
estimation of regression function. The count response is
assumed to have generalized Poisson distribution.. We called
the estimator as local likelihood estimator because it is
determined by local maximum likelihood method. Based on
Taylor development of degree p and considering the
generalized Poisson regression locally, in a neighborhood of
some points of interest of the covariate, we also present the
bias, the variance and the confidence band of the regression
function. We also present some simulation result to show the
behavior of the local likelihood estimator as well as the
confidence band of the regression function.
II. LOCAL LIKELIHOOD ESTIMATOR
Let Y be the response variable, which is a count, and x is a
predictor variables. The distribution of Yi (i=1,2,…,n) at given
xi is following the generalized Poisson distribution, with the
probability density function given by:
1(1 ) (1 )
( , , ) exp , 0,1,2,1 ! 1
ii
yy
i i i ii i
i i i
y yf y y
y
(1)
With
On the Confidence Band of Local Likelihood Estimates in
Generalized Poisson Regression Model
Erni Tri Astuti1, I Nyoman Budiantara
2, Sony Sunaryo
3, Mohamad Dokhi
4
I
The Third Basic Science International Conference - 2013 M23-2
( | )i i i
E Y x
and 2( | ) (1 )i i i iV Y x
The parameter plays as dispersion parameter. When ,
it will reduce to Poisson probability density. When this
model is under dispersed, and when it will over disperse
relative to Poisson distribution respectively [9]. In the local
generalized Poisson regression model, instead of considering
some specified regression function, the dependence of mean
response with a covariate is describe by a smooth
nonparametric regression function s:
exp( ( ))i i
s x (2)
Assume that the function s has a continuous
derivative at the point . For data points in a
neighborhood of or , with h is a
bandwidth, we approximate via a Taylor expansion by a
polynomial of degree p:
0
0 0 0 0
( )( ) ( ) '( )( ) ( )
!
pp T
i i i i
s xs x s x s x x x x x
p x β (3)
where ,
with
0( ), 0,1, ,
!
j
j
s xj p
j (4)
For data points in a neighborhood of , the
contribution to the log likelihood function is weighted by some
kernel function . By assuming generalized
Poisson distribution for response variable , these
considerations yield the conditional local kernel weighted log-
likelihood:
, 0
1
0
ln ( 1) ln(1 ) ln( !)1 1( , , )
i in
i i i
i ip h
i
h i
y y y yL x
K x x
β (5)
where and is a Kernel
weight. The choice of the kernel function is not a crucial
issues, because the result is almost similar for any kind of
kernel function including Epachnecnikov, Gaussian or Boxcar
Kernels [10]. The estimator for regression function, is the
solution of (p+2) equation :
0 021
( )0 , 0,1, ,
(1 ( ))
nvi i
h i i
ij i
y xLK x x x x j p
x
(6)
021
( ) ( )( ) ( 1)
1 ( ) 1 (1 ( ))
ni i ii i i i
h i
i i i i
x y xy x y yLK x x
x y x
(7)
The solution of the system which is called local (maximum)
likelihood estimator can be solved by iterative procedure such
as Newton Raphson Methods. The log-likelihood function
above depends on two quantities, the smoothing parameter (h)
and the order of polynomial (p). The model complexity is
effectively controlled by the bandwidth h. As h increases from
0 to +∞, the model runs from the most complex model
(interpolation) to the simplest model and [10] stated that a too
large bandwidth under parameterizes the regression function
causing a large modeling bias, while too small bandwidth over
parameterizes the unknown function and result in noisy
estimates. Ideal or optimal model is lying between the two
models, which can be obtained by different criteria’s, one such
criteria is cross validation (CV) [11].
Bias and Variance of the Estimator
The estimator β is biased because there is an approximation
error in Taylor expansion (3). By considering a further
expansion with (p+a) degree for approximate s(x), the
estimated bias for local likelihood estimator is given as in [12]
'' * 1 ' *
, 0 , 0ˆ ˆ ˆˆ ( ) ( , ) ( , )p p h p hx x b β L β L β (8)
where ' *
, 0( , )p h xL β and '' *
, 0( , )p h xL β are the gradient vector and
Hessian matrix of the local likelihood given by
* *
* **
, 0
1
0
ln ( 1) ln(1 ) ln( !)1 1( , , )
i in
i i i
i ip h
i
h i
y y y yL x
K x x
β (9)
with * exp( )T
i i ir x β
and
1 2
1 0 2 0 0( ) ( ) ( )p p p a
i p i p i p a ir x x x x x x
(10)
For example, if we set p=1 and a=2, then (8) can be expressed
1*
*
1 0* 31
*
0* 21
ˆˆˆ ˆ ˆ ˆ( ) (1 2 )ˆ ˆ(1 )
ˆ
ˆ ˆ(1 )
nTi
i i h i i i
i i
ni i
h i i
i i
y K x x
yK x x
b β x x
x
(11)
where 0 1ˆ ˆ ˆ, , , p and is the solution of (6),(7) and
ir is
the solution of (9).
On the other hands the estimated variance of the estimator can
be computed by
1 1
' '' ''
0 , 0 , 0ˆ ˆ ˆˆ ( ( ), ) ( , ) ( , )p i p h p hV s x y x x
nV β L β S L β (12)
where ''
, 0( , )p h xL β is the Hessian matrix of (5) and
2
0
1
nT
h i i i
i
K x x
nS x x
And for p=1 and a=2, the estimated variance is
1 1
'' ''0
1 1, 0 1, 0
0
ˆexp( )ˆ ˆ ˆˆ ( , ) ( , )ˆˆ1 exp( )
h hx x
nV β L β S L β (13)
with ''
1, 0ˆ( , )h xL β is Hessian matrix evaluated at β .
Confidence Band of Regression Function
The confidence interval is an important tool for evaluating he
estimator precision. But in nonparametric regression context,
constructing such confidence interval is difficult because of
non-negligible bias. However with our estimated bias and
variance defined previously, we can construct a confidence
interval or confidence band for regression function. Because
the estimated bias and variance involves of higher order
derivative curve, whose estimation can be unstable, they need
to be averaged to prevent from abrupt change [8]. So define
0
1
ˆ ˆˆ ˆ( ) ( ) ( )p
nA
j p j i i
i
b b K x x
(14)
The Third Basic Science International Conference - 2013 M23-3
0
1
ˆ ˆˆ ˆ( ) ( ) ( )p
nA
j p j i i
i
V V K x x
(15)
with
0
0
0
1
( )( )
( )
h i
i i n
h i
i
K x xK x x
K x x
Under some regularity condition [13], the asymptotic
distribution of the local likelihood estimator ˆj at a point x=x0
ˆˆ ˆ( )
(0,1)ˆˆ ( )
A
j j p j D
A
p j
bN
V
(16)
So by invoking asymptotic normality the point wise confidence
interval with (1 ) coverage probability j falls in random
interval
1 /2
ˆˆ ˆ ˆˆ( ) ( )A A
j p j p jb z V (17)
From (4) we have 0( ) !, 0,1, ,j
js x j j p , so equivalently
the confidence band for the regression function
0 1 /2
ˆ ˆˆ ˆ ˆ( ) ( ) ( )j A j A j
p ps x b s z V s (18)
However according to [8], the coverage probability of (17)
or (18) can converge slowly to the nominal level (1 ) . There
are two reason for this. One is that the number of data point
used to estimate the regression function at a particular point
can be much smaller than n and the other is that the bias can
possibly be non-negligible. It will show in our simulation next.
III. SIMULATION RESULT
We conducted some simulation with some purposes. First is
to show the behaviour of the local likelihood estimator as the
bandwidth parameter h and polynomial degree p are increased.
Second the behaviour of confidence band of regression
function before and after averaging process. And finnaly to
show the coverage probability of the confidence band at
nominal level 0.95. For that, we use sample of size n=100, 200
and 500. We generate x from Uniform distribution on [-1,1].
And from each xi we generate the count response from
generalized Poisson distribution with 3 different regression
function
We also use Epanechnikov kernel for weight and the dispersion
parameter is set to 0.2. Fig.(1) shows the behavior of the
estimator when we increased the bandwidth parameter from
h=0.005 to h=0.5 for regression function s1(x).
Fig 1. Estimated regression function (black) with h=0.005, h=0.1, h=0.2 and
h=0.5 and the true regression function (red)
As we can see the estimated curve runs from the complex
model (interpolation) to more simplest model. The ideal
bandwidth or ideal model can be select by considering the
value of CV which is minimum. The influence of the
polynomial degree p can be seen in Fig. 2 as we use s3(x) for
true regression function.
Fig 2. Estimated regression function with p=0 (red), p=1 (green), p=2 (blue)
and the true regression function (black)
As we can see that the higher the degree of polynomial (p=2)
then the estimator can reaches peak or valleys of the data
better than p=0 or p=1, and can approximate the true
regression function nicely.
-1.0 -0.5 0.0 0.5 1.0
0
5
10
15
0.005
X
Y
-1.0 -0.5 0.0 0.5 1.0
0
5
10
15
0.1
X
Y
-1.0 -0.5 0.0 0.5 1.0
0
5
10
15
0.2
X
Y
-1.0 -0.5 0.0 0.5 1.0
0
5
10
15
0.5
X
Y
-2 -1 0 1 2
0
5
10
15
20
x
y
The Third Basic Science International Conference - 2013 M23-4
Fig. 3 The local likelihood estimator (black), 95% confidence band of true
regression function (red) and the true regression function (blue)
Figure 3 is an example of 95% confidence band for true
regression function with coverage probability 0.91. This
coverage probability means that 91% of points in true
regression function are included in the confidence band. The
behavior of this coverage probability is that the estimator can
reach
IV. CONCLUSION
A new approach of nonparametric regression for count
response has been developed using local polynomial technique.
We also derived estimated bias and variance of the estimator
and constructing a confidence band for the unknown regression
function. Simulation result shows that the performance of the
estimator depends on the choice of bandwidth parameter h and
polynomial degrees p. The confidence band of the regression
function shows coverage probability near the nominal level
0.95 as expected
REFERENCES
[1] E.T. Astuti and T. Yanagawa , “Testing Trend for Count Data with
Extra-Poisson Variability”, Biometrics,58, 2002, pp. 398-402.
[2] A. Ferrari, G. Letac and J.Y. Tourneret, J.Y, (2007), “Exponential
families of mixed Poisson distributions”, Journal of Multivariate
Analysis, 98, 2007, pp. 1283 – 1292
[3] J.P. Boucher, M.Denuit and M. Guillen, M., “Risk Classification For
Claim Counts: A Comparative Analysis of Various Zero-Inflated Mixed
Poisson and Hurdle Models”, North American Actuarial Journal, 11:4,
2007, 110-131
[4] F.Famoye, “Restricted Generalized Poisson Regression”, Communication
in Statistics-Theory and Methods, 33, 2002, pp.1135-1154.
[5] J.A. Santos and M.M. Neves,” A Local Maximum Likelihood Estimator
for Poisson Regression”, Metrika, 68,2008, pp. 257-270.
[6] Y.Terzi and M.A. Cengiz,M.A.,” Using of Generalized Additive Model
for Model Selection in Multiple Poisson Regression for Air Pollution
Data”, Scientific Research and Essay, 4:9, 2009, pp. 867-871.
[7] R. Tibshirani and T. Hastie,” Local Likelihood Estimation”, Journal of
the American Statistical Association, 82:398,1987, pp. 559-567.
[8] J. Fan, M. Farmen and I. Gijbels, I, “Local Maximum Likelihood
estimation and Inference”, Journal of the Royal Statistical Society
Series B (Statistical Methodology), 60:3, 1998, pp. 591-608 .
[9] P. C. Consul and G. C. Jain, “ A Generalization of the Poisson
Distribution”, Technometrics, 15:4, 1973, pp. 791-799.
[10] J. Fan and I. Gijbels, Local Polynomial Modeling and Its Application,.
Chapman and Hall. London, 1997.
[11] L. Gyorfi, M. Kohler, A. Krzyzak and H.Walk, A Distribution-Free
Theory of Nonparametric Regression , Springer, New York, 2002.
[12] E.T. Astuti, I.N. Budiantara, S. Sunaryo and M. Dokhi, “Bias dan
Varians dari Estimator Linier Lokal pada Model Regresi Poisson
Tergeneralisir”, presented at Seminar Nasional Pascasarjana XII- ITS,
Surabaya, July 12, 2012.
[13] J. Fan, N.E. Heckman and M.P. Wand, M.P.,” Local Polynomial Kernel
Regression for Generalized Linear Models and Quasi-Likelihood
Functions”, Journal of the American Statistical Association, 90:429,
1995, pp. 141-150.
-2 -1 0 1 2
0
5
10
15
20
0.5
x
y
The Third Basic Science International Conference – 2013 M24-1
1Abstract—Hourly rainfall data has a high variation in time
and has many zero values. The data has a skewed distribution,
which made the modeling and prediction of rainfall becomes more
complicated. In general, these data has non-linear relation in time,
therefore Bayesian neural network (BNN) with adjusting
procedures would be proposed to in this paper. This model will be
compared with natural BNN and standard neural network (NN),
i.e., feed forward neural network (FFNN). The criteria used for
comparison is mean square error (MSE). These methods were
applied for analyzing rainfall data in Jatisrono station, central
Java, Indonesia. The result shows that BNN with adjusting
procedure outperforms the natural BNN and FFNN.
Index Terms— Adjusting procedure, Bayesian neural network,
feed forward neural network, hourly rainfall.
I. INTRODUCTION
ourly rainfall data has a high variation in time and skewed
distribution, which makes the modeling and prediction of
rainfall becomes complicated. In general, the data has non-
linear relation in time. To model this relationship, one of the
time series methods frequently used is neural network (NN).
NN is a method of modeling the nonlinear relationship that is
based on the processing of human neurological system. Several
studies have applied NN in hydrology, including rainfall [1]-
[6].
In the case of forecasting hourly rainfall, it is commonly we
observe over-fitting. To overcome this, the Bayesian approach
is proposed for estimating the NN model parameters [7].
Bayesian Neural Network (BNN) method was first introduced
by [8], [9] and [10] they use a Bayesian approach with network
Back propagation (BP). In the case of time series, BNN
method has been applied, such as is used in the data of Wolfer
sunspot numbers and Canadian lynx [11], import export
economy data [12], the annual rainfall data [13] and modeling
Manuscript received April 7, 2013. This work was supported by the LPPM
and Statistics Department of Institut Teknologi Sepuluh Nopember, Surabaya,
Indonesia.
K. Fithriasari is PhD Student of the Statistics Department, Institut
Teknologi Sepuluh Nopember (ITS), Surabaya, Indonesia (e-mail:
N. Iriawan is with the Statistics Department, Institut Teknologi Sepuluh
Nopember (ITS), Surabaya, Indonesia(e-mail: [email protected])
B. S. S. Ulama is with the Statistics Department, Institut Teknologi
Sepuluh Nopember (ITS), Surabaya, Indonesia(e-mail: [email protected])
Sutikno was with the Statistics Department, Institut Teknologi Sepuluh
Nopember (ITS), Surabaya, Indonesia(e-mail: [email protected])
H. Kuswanto is with the Statistics Department, Institut Teknologi Sepuluh
Nopember (ITS), Surabaya, Indonesia(e-mail: [email protected])
of rainfall and stream flow input (stream) [14].
Many efforts were made by researchers to improve the
model for obtaining the smaller error. One of them is using
adjusting procedures in modeling time series [15], [16]. Based
on the study, BNN with adjusting procedure is proposed to
model and predict the hourly rainfall at Jatisrono station,
Central Java, Indonesia. The results will be compared with the
classical NN e.g. Feed Forward Neural Network (FFNN) and
BNN models without adjustment (natural BNN). Statistical
criteria used for comparison is the Mean Square Error (MSE).
II. FEED FORWARD NEURAL NETWORK (FFNN)
Rainfall at the specified location is affected by the past data
and rainfall in surrounding locations. Suppose that tx is the
rainfall data at tth
time and k t lx
is the past l lags value on
thk locations, then the corresponding FFNN architecture for
modeling hourly rainfall can be shown in Fig 1.
1
2
1
j
J
X1(t-1)
X1(t-2)
X1(t-d)
W11
V1
X1(t)
Input Layer
Hidden Layer
Output Layer
b1J
1
X2(t-1)
X2(t-d)
I
Xk(t-l)
XK(t-d)
1
b2
b11
b1j
Vj
VJ
WIJ
Fig. 1. FFNN architecture for rainfall model
FFNN model according to Fig 1. can be presented as follows
2 1 * 11 1 1
J K d
j jt k t l d k l jj k l
x g b v f b x w
, (1)
where tx is predicted variable (output variable), ijw is matrix
from input to hidden layer, 1 jb is bias for hidden layer, jv is
weight from hidden to output layer, 2b is bias for output
Prediction of Hourly Rainfall using Bayesian Neural
Network with Adjusting Procedure
Kartika Fithriasari, Nur Iriawan, Brodjol S. S. Ulama, Sutikno, and Heri Kuswanto.
H
The Third Basic Science International Conference – 2013 M24-2
layer, .f is nonlinear activation function for hidden layer,
.g is linear activation function for output layer, d is number
of time-lag , J is number of hidden nodes and K is number of
location.
III. BAYESIAN NEURAL NETWORK
Bayesian learning is one of the methods for estimating the
model parameters based on prior and posterior distribution.
NN model estimated by this learning is called Bayesian Neural
Network model. Before doing Bayesian learning for the model
in Eq.1., the prior of the parameters ( ijw and jv ) were
determined. These prior are proposed to follow the normal
distribution [17] which can be written as follows
2
2
,
,
ij w w
ij v v
w Normal
v Normal
where w , 2w , v and 2
v are hyperparameters with the
following distribution 6(0,10 )w Normal , 2 (0.001,0.001)w Invers Gamma ,
6(0,10 )v Normal and 2 (0.001,0.001)v Invers Gamma .
If tx is rainfall in certain time and location, then
tx Eksponensial and its likelihood is represented as
1
1
1
,..., | , | ,
exp
n
ij j ij jn t
t
nn
tt
L x x w v f x w v
x
(2)
In the Bayesian approach, predictions are made by integrating
over the posterior distribution. This posterior can be obtained
by multiplying the likelihood function with the prior
distribution of parameters. BNN has very complex posterior
distribution so the integrations are approximated by Markov
Chain Monte Carlo (MCMC) methods [18]. In MCMC, the
complex ting in of marginalization integrals is approximated via
drawing samples from the joint probability distribution of all
the models parameters and hyperparameters [19]. MCMC
method used in this paper is the Gibbs sampler is implemented
as in WinBUGS.
IV. ADJUSTING PROCEDURE
Adjusting procedure is a modification method of time series
data at the lower level (hourly) generated by the stochastic
model. This procedure was done so that the data are consistent
with a given higher level data (daily). Assume z is known
daily rainfall and sx is generated hourly rainfall data at time s ,
the adjusting procedure is procedure of modifying sx to obtain
adjusted values sx . Define this procedure can be found in [15]
1
/ 1,..., ,H
s s h
h
X X Z X s H
(3)
where H is the number of lower level variable within one
period higher level.
V. RESULT AND DISCUSSION
BNN model will be applied to model the rainfall data
at Jatisrono station, Central Java, Indonesia, captured during
January 2010 to January 2011. The rainfall data has different
monthly characteristics, therefore the modeling for each month
is performed separately. The modeling is done for January
period. Jatisrono rainfall affected by rainfall intensity in
preceding period and rainfall in surrounding locations e.g.
Pabelan. Assume that ty is rainfall values in jatisrono at
time t , hence
tty Eksponential
and 1t t
y .
where ty can be calculated using Eq. 1. Time-lag tried for
modeling is one and 24 time lags [16]. The number of nodes in
the hidden layer is set at two nodes, so 1; 24l , 2K
and 2J . Therefore, the input variable vector is defined as
follows
'
1 1 2 1 1 24 2 24, , ,
t t t tx x x x
x , (4)
where 1 1tx
, 1 24t
x
, 2 1tx
and 2 24t
x
are respectively the
rainfall in one and 24 time lags on Jatisrono and Pabelan.
In this paper to estimate the model parameters used
MCMC performed using WinBUGS. WinBUGS doodle
structure appropriate for modeling of hourly rainfall in
Jatisrono, can be seen in Fig. 2.
Fig. 2. Doodle structure for hourly rainfall model
Posterior mean and median values of the BNN parameters can
be seen in Table 1.
The Third Basic Science International Conference – 2013 M24-3
Table 1. Mean posterior distribution of parameters
Node Mean 2.50% median 97.50%
v[1] -2.149 -2.357 -2.147 -1.941
[2] -1.427 -1.628 -1.424 -1.237
w[1,1] -1568 -2671 -1503 -1004
w[1,2] -1185 -2065 -1150 -519.6
w[2,1] -1822 -3077 -1751 -1193
w[2,2] 325.6 130.8 314.6 598.9
w[3,1] -994.1 -1657 -954 -648.6
w[3,2] 56.56 16.77 52.39 119.8
w[4,1] -2.599 -32.84 -5.457 34.11
w[4,2] 1765 812.3 1739 2933
b2[1] -3.197 -3.388 -3.199 -2.992
b1[1] 24.46 16.09 23.43 41.25
b1[2] 0.4686 -0.02227 0.4544 1.06
The prediction of hourly rainfall by BNN was adjusted using
Eq. 3. Comparison of MSE for the three models namely
FFNN, natural BNN and BNN with adjusting procedures can
be seen in Table 2.
Table 2. MSE value
MODEL MSE
FFNN 2.52
NATURAL BNN 2.50
BNN WITH PROSEDUR ADJUSTING 2.16
From table 2. It appears that the BNN with adjusting
procedure has the smallest MSE. Therefore, we propose to
model hourly rainfall in Jatisrono using BNN method with
adjusting procedures.
VI. CONCLUSION
In This paper, BNN with adjusting procedure has been
applied to model and forecast hourly rainfall at Jatisrono
stations in Central Java, Indonesia. The model is compared by
FFNN and natural BNN. The results show that BNN with
adjusting procedure has the smallest MSE. It shows that the
BNN with adjusting procedure is better than FFNN and natural
BNN.
ACKNOWLEDGMENT
This article is a part of Laboratory’s research grant and
doctoral research at Statistics Department of Institut
Teknologi Sepuluh Nopember (ITS), Surabaya, Indonesian,
granted by LPPM Institut Teknologi Sepuluh Nopember
(ITS). We thank Head of Balai Besar Sungai Bengawan Solo
for providing the hourly and daily rainfall data.
REFERENCES
[1] M. French, W. Krajewski, and R. Cuykendall, “Rainfall
forecasting in space and time using a neural network,”
Journal of Hydrology, 137, 1-31, 1992.
[2] K. Luk, J. Ball, and A. Sharma, “An application of
artificial neural networks for rainfall forecasting,”
Mathematical and Computer Modelling, 33, 683-693,
2001.
[3] G. Lin, and L. Chen, “Application of an artificial neural
network to typhoon rainfall forecasting,” Hydrol.
Process., 19, 1825–1837, 2005.
[4] M. C. Ramírez, H. F. Velho, and N. J. Ferreira,
“Artificial neural network technique for rainfall
forecasting applied to the São Paulo region,” Journal of
Hydrology, 301, 146–162, 2005.
[5] N. Q. Hung, M. S. Babel, S. Weesakul, and N. K.
Tripathi, “An artificial neural network model for rainfall
forecasting in Bangkok, Thailand,” Hydrol. Earth Syst.
Sci., 13, 1413–1425, 2009.
[6] T. Santhanam, and A. Subhajini, “An efficient weather
forecasting system using radial basis function neural
network,” Journal of Computer Science, 7 (7), 962-
966, 2011.
[7] C. Doan, and S. Liong, “Generalization for multilayer
neural network Bayesian regularization or early
stopping,” APHW 2004: The 2nd APHW Conference,
2004.
[8] D. J. MacKay, “A Practical Bayesian Framework for
Backpropagation Networks,” Neural Computation, 4
(3), 448-472, 1992.
[9] D. J. MacKay, “Bayesian Methods for Adaptive
Models,” Ph.D dissertation, Calif. Inst. of Technology,
Pasadena CA. 1991.
[10] W. L. Buntine, and A. S. Weigend, “Bayesian Back-
propagation,” Complex System, 5(6):603-643, 1991.
[11] F. Liang, “Bayesian neural networks for nonlinear time
series forecasting,” Statistics and Computing, 15, 13–
29, 2005.
[12] W. Jiang, L. Zhang, and P. Wang, “Nonlinear time
series forecasting of time dalay neural network
embedded with Bayesian regularization,” Applied
Mathematics and Computation, 205, 123-132, 2008.
[13] X. Pan, and J. Wu, “Bayesian neural network ensemble
model based on partial least squares regression and its
application in rainfall forecasting,” International Joint
Conference on Computational Sciences and
Optimization, 49-52, 2009.
[14] C. Jiang, “The application of Bayesian neural network
in rainfall forecasting,” Key Engineering Materials, 439
- 440, 1300-1305, 2010.
[15] D. Koutsoyiannis, and C. Onof, “Rainfall disaggregation
using adjusting procedures on a Poisson cluster model,”
Journal of Hydrology, 246, 109-122, 2001.
[16] E. Hidayah, “Implementing of temporal rainfall
disaggregation model using bayesian PAR1 model
combined with adjusting and filtering procedure in
sampean catchments area,” Journal of Applied Sciences
Research , 8 (1), 314-320, 2012.
The Third Basic Science International Conference – 2013 M24-4
[17] M. P. Wiper, A. P. Palacios, and J. M. Marin, “Bayesian
software reliability prediction using software metrics
information,” Quality Technology and Quantitative
Management (inpress) , 9 (1), 35-44, 2012.
[18] R. M. Neal, Lecture Notes in Statistics: Bayesian
Learning for Neural Network. New York: Springer-
Verlag, 1996.
[19] J. Lampinen, and A. Vehtari, “Bayesian Approach for
Neural Network - Review and Case Studies,” Neural
Network , 14 (3), 7-24. 2001.
The Third Basic Science International Conference - 2013 M25-1
Abstract— Traditional multivariate statistical process
control (SPC) techniques are based on the assumption on
the successive vector which are independent. In
multivariate process system with presence of serial
correlation, Vector Auto-regressive models (VAR) that
should be used to approximate the system, estimate and
monitor the VAR residuals as a serially independent
multivariate series. VAR models are important class for
analyzing multivariate time series data. In this study, we
considers the problem of monitoring the mean vector of a
process in which observation can be modeled as a first-
order vector autoregressive VAR(1) process and study how
to generalized to VAR(p) process base on residuals. Due to
the effect of shift in mean process on VAR residual chart
by Pan and Jarrett (2007), we investigate the performance
using data from an industrial process to determine the
control limit of monitoring system for multivariate time
series data.
Key words: Vector Auto-regressive models (VAR), VAR(p)
residuals, control limit.
I. INTRODUCTION
N univariate autoregressive model, disturbances are a set of
effects of various factors. This factors have serial
correlations that come from variables process in which
contribute variation in system. Some of them are
unmeasurable, while others variables probably either
measurable or conversely even if modelled in univariate
simple model. In this situation, some of disturbance
components should be potential for autocorrelating processes
in the vector of autoregressive component. On the other hand,
in VAR model, ones a component would be predict, it is
usually refer to order determination for ensure a consistency
criteria of model. Generally, in the theory of time series, order 1p should be determined by simulation empirically, while the
1Post Graduate Student at Department of Statistics Institut Teknologi Sepuluh Nopember, Surabaya, Indonesia
e-mail: [email protected] 2Department of Statistics
Institut Teknologi Sepuluh Nopember, Surabaya, Indonesia e-mail: [email protected] and
[email protected] 3Department of Informatics Engineering
Institut Teknologi Sepuluh Nopember, Surabaya, Indonesia e-mail: [email protected]
2approximation of the MSE matrix will always increased by
the increasing value of p. This means that selection of the
order-p will always correspondences with forecasts precision,
including the precision of the impulse response that depends
on the precision parameter estimation only. In this case, it
require an optimum procedures or criteria to optimize the
VAR model.
Due to general aspect on order determination in time series
theory, it should be determine by a simulation empirically,
while the approximation of mean square matrix always
increase with increasing of p value. This means that order p
selections have an effect to forecast precision, include a
impulse response precision that depend on forecast precision
of parameter estimate only. Some of potential autocorrelated
component can be remove out of the disturbance to AR
component [2]. Moreover, it still require a procedure or
optimum criteria for VAR model, include dealing with moving
average (MA) component structure.
The advantage of VAR(p) models approach is referring to
dynamic process that make it meaningfull because more
reasonable to the real processes. A real example can be seen in
VAR(p) models that, all of systematic variables will be
accommodated in this model, and just white noise and error
measurement as a part of disturbance. Other advantage of
residual VAR model is it can be estimated with OLS
procedure instead of the more complex MLE procedure [3,4].
In many application, investigation to the response impulse can
be extend to high-dimensional system to find out response
within variables. This analysis be required when there is
reaction of one variable to impulse of other variable can be
identified causally.
Moreover, the circumstance of assumption about
autocorrelation structure in a process still remain other easy
circumstance for resolve either through on data generating
process as well as on multivariate normal generating based on
uncorrelated residuals. Properties of stasionerity or time
invariant on data generating using VAR(p) models are
important requirement that can be used in determining
estimator behavior and forecast calculation, as well as in
interval forecasting. The properties mention above, also using
to ensure mean, variance, and auto-covariance invariant over
time. Some cases in economic field shows that models
construction based on data generating, sometime have not
guaranteed and satisfied the stationarity assumption. Main
axamination of test can be dealt to model stability checking, ,
according to fact that stability hence stationarity [2].
Following to non random effect on multivariate time series,
shift of structure parameter as impact of accumulation effect
Vector Auto-Regressive Control Chart and Its
Application in Industry
1J. K. Wororomi,
2M. Mashuri,
2Irhamah and
3A. Z. Arifin
I
The Third Basic Science International Conference - 2013 M25-2
on shock occurrence in variables. Commonly, those effect
accumulation can be determined via coefficient matrices of
MA representation by using numeric approximation due to
structural change as an impact of shift processes. In [3,4], this
approximation by using control chart constructing due to
controlling of structure changes on mean shift, disperse shift,
and coefficient matrices shift.
However, this paper proposed to assert interaction between
variables in VAR models related to covariance matrix
estimation and order p on particular period by the function of
impulse response empirically. In case study of Woodmod data,
we investigate the innovations matrices of various models in
simulation to conduct control limits on phase I controlling
using multiple Woodmod data.
II. VECTOR AUTOREGRESSIVE MODEL
A. Review Stable Model
The order p of VAR Model or VAR(p) can be expressed by
(1)
with random vector of , denoted
to coefficient matrices , as vector
intercept of . While denoted as
white noise or innovation process of K-dimensional with
and for . In
stable condition, covariance matrix can be assumed non-
singular.
Investigation to consistencies of the VAR(p) models on (1),
can be initiated from VAR(1) model
(2)
Distribution of should be determined uniquely by
distribution of process. If eigenvalue of matrix have
modulus value less than 1, then VAR(1) process is called as
stable process. This condition equivalent to
. Moreover, VAR(p)
model can be extended to p>1 or more precisely, is a
VAR(p) process as well in (2), that is correspond to Kp-
dimensional of VAR(1)
(3)
can be defined, with
, ,
with mean vector and
as the auto-covariance.
, and matrix with size
.
The process is obtained as or mean and covariance
can be expressed as which constant for all t and
the auto-covariance are also time invariant.
Formally is stable process
(4)
In the other words, process in (1) is stable if satisfied (4)
and
(5)
with denoted as lag of i-th matrix on MA
representation as
(6)
On the other hand, linkages of the VAR models which
constructed via MA representation on [2] as and
, for because and are
absolute summable which involves the white noise process
and so process determined by white noise or innovation
process. We also convey that, for given assumption has been
addressed to the process give direct impact to process.
The model build-up here is consider to (9) and multivariate
innovation algorithm can be refer to [1].
B. Impulse Response Function
The Analysis of impulse response function in multivariate
time series is often of interest to know the response or
interaction within variables on the system.
In applied work, it is often of interest to pay attention on the
accumulated effect on the period of shock occurance in one
variable. This effect can be determined by summation of MA
coefficient matrix. Suppose the k-th column of
which contain response accumulation on n-period to the shock
unit within k-th variable in the system. This quantity are
recognizing as n-th interim multipliers (i.e impulse response).
The total of accumulation effect for all future period will be
obtained by taking summation of all MA coefficient matrix.
The MA Operator is an inverse form of the VAR
operator that can be expressed by
as a term of long-run effect that
can be obtained from
(7)
Determination of the response impulse function via MA
representation as in (4) can be rewritten in form
(8)
with as matrix with size of and
as white noise process with covarian matrix equal
to identity matrix, . The response impulse function is
(9)
with , the elements of here can be interpreted as
response in the system to innovation . For given index of j,k
on the elements of can be interpreted as the effect
occurrence in j-th variables of innovation unit on k-th
variables which have been occurred on the previous i-th
period.
The Third Basic Science International Conference - 2013 M25-3
C. Variance Error Variance Decomposition
The next investigation are how to accomplish the innovation
to the system recognizing, in particular to VAR model
interpretation. Suppose that identification scheme in MA term
which has build recursively with orthogonal innovation white
noise. In optimal forecast error context, h-th step will be
written as
(10)
Let mn-th elements of denoted as so that, h-th step
forecast error of j-th component on process is
(14)
since are uncorrelated and have an unit variance, the
mean square error of or
.
with the result that
(11)
with k-th columns of .
Equation (11) usually will be interpreted as innovative
contribution on k-variable of variance forecast error. This
analogy to MSE of h-step forecast j-variable that has been
presented on [2] as
(12)
with
III. RESULT AND DISCUSSION
As a case study, we consider a multi-dimensional system
consisting first and second differences to adjust the woodmod
dataset. Let shows five variables
which described as first and second differences on the figure.1
are respect to number of fibers per square milliliter in
Springwood (FSp), number of fibers per square milliliter in
Summerwood (FSm), fraction of Springwood (fSp), fraction
of light absorption by Springwood (fSp1), and fraction of light
absorption by Summerwood (fSm1).
The example as mention above is a part of real-life
production process and we wish to show the effectiveness of
using VAR residual chart to detect special causes in multiple
and or/ multivariate time series. The raw data are found having
serial correlation in five variables.
In the stage of data pre-processing, the transformation by
first and second differences has shown stationarity on data
Woodmood raw data as depict on figure 1.
Due to generation of VAR residuals chart procedure for
obtain an approriate innovation matrix from Woodmod data,
we estimated the VAR parameters using OLS method, and
choose a VAR(1) for second differences as to appropriate
VAR model process with innovation matrix has been positive
semi definite.
VAR Modelling
Generating data process based on second differences
VAR(1) for p=5,T=1000, and K=5 depict on figure 2, it shows
that VAR (5) process is also stationary with positive definite
of the covariance matrix. We have extend the simulation to
some input parameters (i.e for p=1,2,3,4; T=30,50,100,500) in
this simulation to justify asymptotically behavior of VAR
residual before applied VAR control chart in phase I.
0 500 1000-5
0
5
10Y,1
0 500 1000-5
0
5
10Y,2
0 500 1000-5
0
5
10
15Y,3
0 500 1000-5
0
5
10
15Y,4
0 500 1000-5
0
5
10Y,5
Figure 2. VAR(p) generating process
VAR(1) residual control chart
The true process is unknown, but we can investigate the
consistency of the VAR(1) models based on second
differences in MA term. Particular investigation of the VAR
residual model can be interpreted on MA term or impulse
response as shows in figure 5. in Appendix.
0 2 4 6 8 10 12 14 16 18 20-0.2
-0.15
-0.1
-0.05
0
0.05
0.1
0.15
0.2
Monthly Production
Nu
mb
er
of fib
ers
pe
r sq
ua
re m
illilite
r &
its
fra
ctio
n
FSp
FSm
fSp
fSp1
fSm1
(a). Woodmod raw data after first difference
0 2 4 6 8 10 12 14 16 18-0.4
-0.3
-0.2
-0.1
0
0.1
0.2
0.3
Monthly Production
Nu
mb
er
of fib
er
pe
r sq
ua
re m
illite
r &
its
fra
ctio
n
FSp
FSm
fSp
fSp1
fSm1
(b). Woodmod raw data after
second difference
Figure 1. Raw data transformation
The Third Basic Science International Conference - 2013 M25-4
When we set VAR(1) residual models as appropriate in this
model, then we presetting UCL at type I error of 0.0027 and
0.005 on VAR residual chart. We found signals at the almost
on all point, except in 3th ,4
th,6
th,7
th,and 15
th. Conversely, when
we change type I error to 0.005, limit of UCL increase and
reduce the signals of limit control.
IV. CONCLUSION AND SUGGESTION
In this study, we considers the problem of monitoring the
process in which observation can be modeled as a first-order
vector autoregressive VAR(1) process and study how to
generalized to VAR(p) process base on residuals. Due to the
effect of shift in mean process on VAR residual chart by Pan
and Jarrett (2007), we investigate the performance using data
from an industrial process depend on structure of the time
series.
T2 chart using Chi-Square distribution with α=0.0027 give
more unrealistic when designed on Woodmod data or time
series data that come from small sample. In our design of
VAR residual control chart, it shown some fault detection on
all variables. To overcome these problem (result), we can use
other residual model by interpreted on MA term or impulse
function simultaneously (causality analysis) to investigate best
innovation matrix that provide parsimonious model.
APPENDIX
Model estimating using OLS has been obtained innovation
matrix and its coefficient matrix from VAR residual, and by
the Cholesky decomposition, we investigate the impulse
response and FEVD of VAR model with various input
parameters (i.e for p=1,2,3,4; T=30,50,100,500, and 1000).
As an example we give causality analysis to depict the
impulse response In fig.5 for p=5,T=100, and K=5.
REFERENCES
[1] Brockwell P.J., and Davis R.A., (1991), Time Series: Theory and
Methods, second edition, Springer-Verlag, New York,Inc.;
[2] Lütkepohl H., (2005), New Introduction to Multiple Time Series
Analysis, Springer_verlag Berlin Heidelberg;
[3] Pan,X. (2005), Notes on shift effects for T2-type charts on multivariate
ARMA residuals, Computers and Industrial Engineering 49 (2005) 381-
392
[4] Pan X. and Jarrett J., (2007), Using vector autoregresive residual to
monitor multivariat processes in presence of serial correlation, Int. J.
Production Economics 106 (2007) 204-216;
[5] J. Jones. (1991, May 10). Networks (2nd ed.) [Online]. Available:
http://www.atm.com
[6] (Journal Online Sources style) K. Author. (year, month). Title. Journal
[Type of medium]. Volume(issue), paging if given.
Available: http://www.(URL)
[7] R. J. Vidmar. (1992, August). On the use of atmospheric plasmas as
electromagnetic reflectors. IEEE Trans. Plasma Sci. [Online]. 21(3). pp.
876–880. Available: http://www.halcyon.com/pub/journals/21ps03-
vidmar
2 4-1
0
1
2
Y1 to U
1
2 4-0.1
0
0.1
Y1 to U
2
2 4-0.2
0
0.2
Y1 to U
3
2 4-0.05
0
0.05
Y1 to U
4
2 40
0.01
0.02
0.03
Y1 to U
5
2 4-2
-1
0
1
Y2 to U
1
2 4-1
0
1
2
Y2 to U
2
2 40
0.1
0.2
Y2 to U
3
2 4-0.2
0
0.2
Y2 to U
4
2 4-0.1
0
0.1
Y2 to U
5
2 40
1
2
3
Y3 to U
1
2 4-0.5
0
0.5
Y3 to U
2
2 40
0.5
1
Y3 to U
3
2 40
0.1
0.2
Y3 to U
4
2 40
0.02
0.04
0.06
Y3 to U
5
2 40
1
2
3
Y4 to U
1
2 4-1
-0.5
0
0.5
Y4 to U
2
2 40
0.1
0.2
Y4 to U
3
2 40
0.2
0.4
Y4 to U
4
2 40
0.05
0.1
Y4 to U
5
2 4-1
-0.5
0
0.5
Y5 to U
1
2 4-0.5
0
0.5
Y5 to U
2
2 40
0.2
0.4
Y5 to U
3
2 40
0.5
1
Y5 to U
4
2 40
0.2
0.4
Y5 to U
5
Figure 5. Impulse responses
0 2 4 6 8 10 12 14 16 180
5
10
Observation number
T S
qu
are
S
ta
tistic
T-Square for VAR residuals
0 2 4 6 8 10 12 14 16 180
5
10
Observation number
T S
qu
are
S
ta
tistic
T-Square for VAR residuals
Figure 4.
(a) T2 chart using Chi-Square distribution with α=0.0027;
(b) T2 chart using Chi- distribution with α=0.005
(a)
(b)
The Third Basic Science International Conference - 2013
M26-1
1Abstract—Extreme rainfalls events usually have negative
effect for environment and human. It can cause flood or
landslide. Therefore, prediction of extreme rainfall events
for different return period is essential for safe and optimal
design structure. In this paper we apply Peak Over
Threshold (POT) method to predict extreme rainfalls for
several return periods in Malang Regency. We investigate
characteristic of extreme rainfalls by fitting shape and
scale parameters of Generalized Pareto Distribution. Mean
residual life plot and assessment of shape parameter
stability across a range of different thresholds are used to
determine threshold value. Maximum likelihood method is
used for parameter estimation and probability plots,
quantile plots, return level plots and density plots for
model validation. Using daily rainfalls data for total period
of 14 years from Januari 1996 to December 2009 in
Malang Regency, we show that generalized pareto
distribution fitted the data well then extreme rainfalls in
different return periods are predicted using the model.
Index Terms— Extreme rainfalls, generalized pareto
distribution, maximum likelihood, mean residual life plot, peak
over threshold, return period, threshold value.
I. INTRODUCTION
Extreme rainfalls events usually have negative effect for
environment and human. It can cause flood or landslide which
is occured immediately. Rainfalls in Malang Regency are
important to support of agriculture sector. However, extreme
rainfall can be serious threat. Therefore investigation of the
extreme rainfalls are required for mitigation efforts.
Unfortunately, we do not know exactly when the next
extreme rainfalls with certain level will occure. Thus, we can
Manuscript received April 6, 2001. This work was supported by PGB ITS
under Grant No. : 0750.256/I2.7/PM/2011.
Amran, Post Graduate Student at Department of Statistics, Institut
Teknologi Sepuluh Nopember, Surabaya, Indonesia (e-mail:amranihsani@
gmail.com).
Iriawan N., Department of Statistics, Institut Teknologi Sepuluh Nopember,
Surabaya, Indonesia.
Subiono, Department of Mathematics, Institut Teknologi Sepuluh
Nopember, Surabaya, Indonesia.
Irhamah, Department of Statistics, Institut Teknologi Sepuluh Nopember,
Surabaya, Indonesia.
only estimate the probabilities of level extreme in the future
and this can be done by extreme value analysis.
The study of extreme events are one of interesting field in
natural science, particularly, in extreme value analysis. The
goal of extreme value analysis is to quantify the stochastic
behaviour of a process at unusually high or low levels. The
stochastic behaviour of extreme events can be analysed by their
probability distribution function. Estimating probability of
extreme event has become an important statistical disicpline in
applied science and frequently used for environmental process
modeling.
Commonly, estimation of probability distribution of extreme
events are performed by Block Maxima (BM) method for
Generalized Extreme Value (GEV) distribution or Peak Over
Threshold (POT) method for Generalized Pareto (GP)
distribution. Both of BM and POT method have been used
widely to study extreme events. Adamowski [1], analyse GEV
distribution of daily precipitation data to study effect of
underlying trend in Ontario, Buishand [2], estimates extreme
rainfalls through GEV distribution of daily rainfall data from
several sites in Netherland. Davison and Smith [3] using POT
method to analyze extreme rainfalls, Leahy and Kiely [4],
investigate short duration rainfalls extreme using GP
distribution for rainfalls data in Ireland.
BM method employ series of maximum observation in
certain range or block to characterize parameters of GEV
distribution, thus, there are some extreme observation which
are exclude in the analysis. Conversely, POT method consider
all of extreme observation in the analysis, thus this method use
data more effecient [9].
In this paper, we apply POT method to predict the next
extreme rainfalls in Malang regency which is has not been done
yet. The prediction is denoted by return level, it runs for
several return periods and temporal dependence is evaluated
for increasing the accuracy of GP model.
II. METHODOLOGY
A. Data sets
Daily rainfalls data were measured at Ngajum station in the
Malang Residences. The location has 349 m heights from sea
level. Extreme rainfalls were determined by selecting certain
threshold value. The number of 5145 data were measured
Application of the Peak Over Threshold Method for
Extreme Rainfalls Modeling in Malang Regency
Amran, Iriawan N., Subiono, and Irhamah
The Third Basic Science International Conference - 2013
M26-2
during 1996 to 2009 would be characterized their distribution.
The skewness values is 3.95, it indicates asymmetric
distribution .
B. Generalized Pareto Distribution
Let X be a sequence of independent and identical distributed
random variables. For a certain threshold value u, define Y = X
– u, known as excess [10]. The distribution of Y, conditional X
> u can be approximated by GP distribution [7], [8]:
F(y; , ) = (1)
where y > 0, and are shape and scale parameters
respectively. Shape paremeter value shows behaviour of tail of
distribution. If < 0 then the GP distribution has a point until
the end that is known as short-tailed distribution, when = - 1,
GP known as uniform distribution. If = 0, GP behave as
exponential distribution. On the other hand if > 0 known as
heavy-tailed distribution. Maximum likelihood method will be
employed to estimate and values.
C. Return Level
Return level (RLN) is the level expected to be exceeded once
every N years [6]. The N- Return period is usually specified in
years. Suppose that GP distribution is appropriate model for y,
the N period return level is denoted as follows:
(2)
where u is threshold value, ny is number of observations per
year and u is probability of an individual observation
exceeding u [6], [9].
Return level RLN is described by a simple graph known as
return level plots for easy interpretation. Return level plots
tend to concave line with no finite bound for > 0, linear line
for = 0, and convex line for < 0.
D. Model Validation
We use four steps validation for assessing the quality of a
fitted GP model, these are probability plot, quantile plot, return
level plot, and density plot. GP model fit data well, if
probability plot and quantile plot of model and data points
could be approximated by a linear line, return level plot will
shows suitability between shape parameter values and their
graphs, and density estimation should be consistent with the
histogram of data [6]. GP model will fit with data if results for
these steps are convenient.
III. RESULTS
We use R-package extRemes for daily rainfalls data
modeling, in Ngajum station.
A. Threshold Selection
Figure 1 shows mean residual life plot over interval of
threshold values. Mean residual life plot is presented with
approximate 95% confidence intervals. The graph shows
curvature from u = 0 to u ≈ 35, approximately linear from u ≈
35 to u ≈ 60, and decrease after u ≈ 60. Since, a reasonable
threshold values are obtained form linearity between mean
excess values and interval of thresholds, the plot suggests that
the possible interval i.e. [35, 60]. Threshold value u is
convenient if modified scale parameter and shape parameter are
stable above u [6]. The graphs are seen in fig. 2.
Fig. 1 Mean residual life plot for daily rainfalls data in Ngajum station.
Figure 2 shows modified scale parameter and shape
parameter against threshold values. In fig. 2 we can see that the
pattern is change for high threshold values that was suitable
with the change in pattern in the mean residual life plot.
However, a reasonable interval of possible threshold value that
is [30, 45]. Fig. 2 shows shorter interval compare than interval
from fig. 1. Since, interval in fig. 2 also include in interval in
fig. 1, hence, interval of possible threshold value [30, 45]
appears reasonable.
B. Parameter estimation and Validation
According to results which are obtain from threshold
selection process, then maximum likelihood method was
performed for estimating parameters of GP distribution and
validation process for measuring quality of model [5], [6]. The
results are showed in Table 1.
Table 1 shows parameter estimation with their
corresponding standard errors for several threshold u. Scale
parameter and shape parameter reveal stability over threshold
values. Scale parameters are close to 21 and shape parameters
are close to zero with small standard error values.
TABLE I
PARAMETER ESTIMATION BY MLE
The Third Basic Science International Conference - 2013
M26-3
Parameters
u
30 35 40 45
scale 21.55
(1.753)
22.343
(2.043)
20.956
(2.242)
21.072
(2.664)
shape -0.014
(0.059)
-0.035
(0.066)
0.001
(0.081)
0.003
(0.098)
loglikelihood 1294.104 1009.817 812.663 631.895
Exceedance rate
(per year) 23 18 14 11
Nu 319 248 201 156
Nu = number of exceedances
Temporal dependency is one of important aspect in POT
method. Dependence series usually appeared in extreme
rainfalls. However, the main assumption of GP model requires
independency of exceedances series. Thus, according to the
assumption, we also run declustering process [6]. But
parameters estimation which are obtained after declustering
process are not significantly different.
Plots in fig. 3a – 3d, consist of probability plot, quantile plot,
return level plot, density plot. We can see that all diagnostic
plots show valid result for all possible threshold values.
Probability plot and Quantile plot of model and rainfalls data
are close to linear line, return level plots close to linear, the
plots are suitable for all shape parameter estimation which are
close to zero. Density plots for model and data are fit.
Therefore, the model could be used to predict extreme through
return level for different return periods.
Fig. 3a. Diagnostic plots for threshold value, u = 30 mm.
Fig. 3b. Diagnostic plots for threshold value, u = 35 mm.
Fig. 3c. Diagnostic plots for threshold value, u = 40 mm.
Fig. 2. Modified Scale and Shape parameters
The Third Basic Science International Conference - 2013
M26-4
Fig. 3d. Diagnostic plots for threshold value, u = 45 mm.
Return level take in to account in order to predict extreme
rainfalls. Based on parameters values which are estimated by
maximum likelihood method and assuming that extreme
rainfalls from stationary process, return level in (2) are
provided in Table 2 as follows:
TABLE II
RETURN LEVEL FOR THRESHOLD VALUES
N Return Level (mm)
u = 30 u = 35 u = 40 u = 45
5
128.704 127.683 129.579 130.043
(114.531,
152.310)
(114.353,
152.597)
(114.748,
157.749)
(114.963,
161.660)
10
142.642 140.789 144.156 144.819
(124.182,
169.581)
(123.519,
169.226)
(124.361,
176.910)
(124.447,
181.930)
25
160.866 157.639 163.438 164.394
(135.737,
192.164)
(134.215,
190.606)
(135.655,
202.255)
(135.354,
208.782)
50
174.501 170.035 178.032 179.233
(143.654,
209.059)
(141.353,
206.334)
(143.244,
221.439)
(142.516,
229.139)
Return levels tend to stable for interval threshold value and
it is increase for all combination of return periods. There is a
different phenomenom showed in return level for u = 35 mm.
For every return period, return level will increase for higher
threshold value, however, it did not happen for u = 35 mm.
Return levels of 35 mm are minimum for all return periods. It is
needed a further investigation to evaluate this phenomenom.
Generally, return level in Ngajum station are vary for every
return period and it can be seen in Table 2.
.
IV. CONCLUSIONS
Model GP distribution has been built for daily rainfalls data
in Ngajum station, Malang Regency. Threshold selection use
mean residual life plot and stability parameters plot to select
threshold value. Both of the graph have a similar pattern.
These analysis suggest that interval of possible threshold value
are [30, 45].
Based on the interval threshold values, maximum likelihood
method was performed on 30 mm, 35 mm, 40 mm, and 45 mm
and validation model was performed to assess quality of model.
All diagnonstic plots indicated that model fitted data well.
Therefore, the model could be used to predict extreme through
return level for different return periods.
Return levels tend to stable for interval threshold value and
increase for all combination of return periods. Generally, return
level in Ngajum station are (127.683, 130.043) for 5 years
return period, (140.789, 144.819) for 10 years return period,
(157.639, 164.394) for 25 years return period, and (170.035,
179.233) for 50 years return period.
There are some possible extension in this paper. How to
determine the best threshold values for more convenient way is
still needed. Stationary process assumption for extreme rainfall
is required for long time return period but, it is interesting to
evolve return level for nonstationary process.
REFERENCES
[1] J. Adamowski, K. Adamowski, and J. Bougadis, “Influence of trend on
short duration design storms,” Water Resour Manage, 24(3):401–413,
2010.
[2] T. A. Buishand, “Extreme rainfall estimation by combining data from
several sites,” Hydrologkal Sciences - Journal - des Sciences
Hydrologiques, 36,4, 8/ 1991.
[3] A.C. Davidson and R. L. Smith,” Models for exceedances over high
threshold (with discussion),” J. Roy. Stat. Soc. B, 52, 393-442.
[4] P. G. Leahy and G. Kiely, “Short duration rainfall extremes in Ireland:
Influence of climatic variability,” Water Resour Manage, 2010, DOI
10.1007/s11269-010-9737-2.
[5] D.Z.P. Bermudez and S. Kotz, ,” Parameter estimation of the generalized
Pareto distribution-Part I”. Journal of Statistical Planning and
Inference, 140, 1353-1373, 2010.
[6] S. G. Coles, An Introduction to Statistical Modeling of Extreme
Values. London: Springer-Verlag, 2001.
[7] M. Falk andA. Guillou,” Peaks-over-threshold stability of multivariate
generalized Pareto distributions,” Journal of Multivariate Analysis, 99,
715-734, 2008.
[8] J. Picklands, Statistical inference using extreme order statistics. Ann
Stat 3:119–131, 1975.
[9] L. Fawcet and D. Walshaw, “Modeling environmental extremes,” in 19th
conf. of The International Environmetrics Society, Kelowna, Canada,
June 8th , 2008.
[10] I. Li, W. Cai, E, and. P. Campbell, “Statistical Modeling of Extreme
Rainfall in Southwest Western Australia,” Journal of Climate, 18, pp.
852–863, 2005.
The Third Basic Science International Conference - 2013 M28-1
Abstract— Nonparametric multivariable regression model is a
development of nonparametric regression model with one
variable predictor. The smoothing spline function can be used to
approximate nonparametric multivariable regression models. In
order to obtain estimator and to construct confidence interval of
smoothing spline curve in the nonparametric multivariable
regression model, we can use bayesian approach. The smoothing
parameters selection simultaneously in nonparametric
multivariable regression model using the Generalized Maximum
Likelihood (GML) method. By computing posterior mean and
posterior variance of smoothing spline function, we obtain the
confidence interval for the smoothing spline function k
f , k =
1,...,q. We proposed this method with simulation data.
Keywords—Bayesian Confidence interval, GML,
Nonparametric multivariable, Smoothing spline.
I. INTRODUCTION
Smoothing splines have been used successfully in a wide
range of applications requiring flexible nonparametric
regression models. It is highly desirable to have interpretable
confidence intervals for these estimates for various reasons, for
example, to decide whether a spline estimate is more suitable
than a particular parametric regression. A parametric
regression model may be considered not suitable if a large
portion of its estimate is outside of the confidence intervals of a
smoothing spline estimate.
One way for constructing confidence intervals for
nonparametric estimates is bootstrap and bayesian approach.
The disadvantage of the bootstrap intervals is that they are
computer intensive. Reference [5] and [4] used bayesian
confidence interval for a smoothing spline in nonparametric
model. Reference [6] compared the performance of bayesian
confidence interval with bootstrap confidence interval for
Rita Diana is a student at Department of Statistics, Faculty of Mathematics
and Natural Sciences, Sepuluh Nopember Institute of Technology, Surabaya,
Indonesia; (corresponding author to phone: +6285232078886; fax:
+62315922940; e-mail: [email protected]).
I. Nyoman Budiantara is a lecturer at Department of Statistics, Faculty of
Mathematics and Natural Science, Sepuluh Nopember Institute of Technology,
Surabaya, Indonesia; (e-mail: [email protected]).
Purhadi, is a lecturer at Department of Statistics, Faculty of Mathematics
and Natural Science, Sepuluh Nopember Institute of Technology, Surabaya,
Indonesia; (e-mail: [email protected]).
Satwiko Darmesto is a senior lecturer at Center for the Study and Education
and Training Apparatus I, National Institute of Public Administration,
Bandung, Indonesia; (e-mail: [email protected]).
smoothing spline in nonparametric model via simulations.
Reference [1] used bootstrap confidence interval for regression
spline truncated in nonparametric model. Reference [3] also
used bayesian confidence interval for regression B-splines in
nonparametric model.
Furthermore, reference [2] constructed bayesian confidence
interval as a penalized spline with mixed model approach in
nonparametric model. Reference [10] used bootstrap
confidence interval for regression spline in nonparametric
additive model. Reference [8] extended method of [2] to
construct confidence interval for penalized spline in
nonparametric additive model. Reference [9] used bayesian
confidence interval for penalized spline in nonparametric
additive model with non-Gaussian data.
The description above shows that research on bayesian
confidence interval for regression spline dan penalized spline in
nonparametric multivariable model have been done. However,
the research on bayesian confidence interval for smoothing
spline in nonparametric multivariable model has not yet been
done. In this paper, we provide some evidence that the
bayesian confidence intervals for smoothing splines that we
construct have an average coverage probability across the
estimated function. The optimal smoothing parameters
selection method simultaneously in nonparametric multivariable
regression model using GML. We proposed this method with
simulation data.
II. BAYESIAN CONFIDENCE INTERVAL FOR
SMOOTHING SPLINE
A. Bayesian Smoothing Spline for one variable
Define a nonparametric regression model as
( ) , z [ , ]j j j jy f z a b , j = 1,2,…,n
where f is unknown function and εj are zero-mean independent
random errors with a common variance σ2. Assume a prior for
f as
1/2
1
( ) ( ) ( )m
v v
v
f z z g z
,
(1)
where 1 2( , ,..., ) ~ ( , ), m N α 0 I , and are
positive constants. ( ); [ , ]g z z a b is a zero-mean Gaussian
stochastic process with covariance function ,
1, 1( , )
n n
j l j lz z
V
Bayesian Confidence Interval for Smoothing Spline in
Nonparametric Multivariable Regression Model
Rita Diana, I. Nyoman Budiantara, Purhadi and Satwiko Darmesto
The Third Basic Science International Conference - 2013 M28-2
with 1 1 2( , ) ( ) ( ) [( 1)!] .
b
m m
j l j l
a
z z z u z u m du
Moreover,
, 1, 2,..., v v m and ( )g z are mutually independent.
Let 1( ,..., ) ,T
m α
,
1, 1={ ( )} ,n m
v j j vz Z
1( , , )m
where
-1( ) ( 1)!,v
v j jz z v v=1,2,...,m, then (1) can be written as
1/2( ) ( )Tf z g z α
and we also obtain
1/2 2( ) ~ ( , )Tg z N y Zα + ε 0 Z Z V I (2)
and 1/2( ) ( ) ~ ( , ( , ))T Tf z g z N z z α 0
(3)
Furthermore,
( )E f y Z + ψ
(4)
where 1( ( , ), , ( , )) .T
nz z z z ψ Let 2 /n and / .
Using properties of multivariate normal random variables and
(2), (3) and (4), we have
1 1( | ) ( ) ( )T T T TE f n n y Z ZZ V I y ψ ZZ V I y
(5)
and
1
| ( , ) ( )
( ) ( )
T T T T
T
Var f z z
n
y Z ψ
ZZ V I Z ψ
(6)
2 1
1 1
( , ) ( ( ) )
2 ( ( ) ) ( )
T T T
T T T T T
z z
I Z ZZ M Z
Z ZZ M ψ ψ ZZ M ψ
Reference [5] showed that if ,U V I n
1lim( )T
ZZ U y
1 1 1 1 1( ( ) )T T U U Z Z U Z Z U y
(7) 1 1 1 1lim ( ) ( )T T T
Z ZZ U y Z U Z Z U y
(8)
Combining results in (5), (7) and (8), [7] showed that
1 1 1 1 1 1 1 1
ˆ lim ( | )
( ) ( ( ) )T T T T T T
f E f
y
Z U Z Z U y ψ U U Z Z U Z Z U y
(9)
and
1 1 1 1 1
1 1 1 1 1
lim |
= ( , ) ( ) 2 ( )
( ( ) )
T T T T T
T T T
Var f
z z
y
Z U Z Z U Z Z U ψ
ψ U U Z Z U Z Z U ψ
(10)
If 1 1 1n VU U V I U then 2ˆlim | ( )Var f
y A where
2 ˆˆ n , 1 1 1 1 1( ) ( ( ) )T Tn A I U U Z Z U Z Z U and
ˆ ( ( )) .T n m y I A y
Therefore, by calculating each posterior mean and posterior
variance of f, we can construct 100(1 )% confidence
intervals for smoothing spline functions f(zj), j = 1,...,n in
nonparametric regression model is thus
2
2
ˆ ˆ( )j jjf z z a , j = 1,...,n (11)
where 2 is an estimate of 2 and jja are diagonal elements
of the matrix ( )A .
B. Bayesian Smoothing Spline for multivariable
A nonparametric multivariable regression model assumes
that
1
( ) , z [ , ]q
j k kj j kj k k
k
y f z a b
, j = 1,2,…,n
(12)
where fk are unknown functions and εj are zero-mean
independent random errors with a common variance σ2.
Assume a prior for fk as
1/2 1/2
1
( ) ( )km
kv kv k k k k
v
f z g z
(13)
where 1 2( , ,..., ) ~ ( , ), k k k km N α 0 I , and are
positive constants, kα and ( )k kg z are mutually independent,
and ( ); [ , ]k k k k kg z z a b is a zero-mean Gaussian stochastic
process with covariance function ,
1, 1( , )
n n
k k k k kj kl j lz z
V
with 1 1 2( , ) ( ) ( ) [( 1)!] .k
k
b
m m
k kj kl kj kl
a
z z z u z u m du
Let 1( ,..., ) ,T T T
qα α α 1( ,..., ) ,
k
T
k k km α
1( , , ),qT T T
,
1, 1={ ( )} ,n m
k kv kj j vz T
1 , , ,qΦ
1, ,kk k km
where
-1( ) ( 1)!,v
kv kj kjz z v v=1,2,...,mk; k=1,2,...,q, then (12) can be
written as 1/2 1/2
1 1 1
( ) ( )q q q
T
k k k k k k k
k k k
w f z g z
Φ α and
1/2 1 2
1
( ) .q
k k kk
y Tα + g z ε Hence, we also obtain
2
1
~ ( , )q
Tk k
k
N
y 0 TT V I
(14)
and 1 1
( ) ~ ( , ( , ))q q
T
k k k k k k
k k
w f z N z z
0 Φ Φ
(15)
Furthermore,
1
( )q
T
k k
k
E w
y TΦ+ ψ
(16)
where 1( , ), , ( , ) .
T
k k k k k knz z z z ψ
Let 2 /n and / .
Using properties of multivariate
normal random variables and (14), (15) and (16), we have
The Third Basic Science International Conference - 2013 M28-3
1
1
1
1
1 1
ˆ( | ) ( | )
= ( )
( )
k
q
k
k
qT T T
k k
k
q qT T
k k k k
k k
E w E f
n
n
y y
Φ T TT V I y
ψ TT V I y
(17)
and
1 1
1
1 1
| { ( )
( ) ( )
q qT T T T
k k k k
k k
q qT
k k k k
k k
Var w
n
y Φ Φ Φ T ψ
TT V I TΦ ψ
(18)
2 1
1 1
1
1
1 1
ˆ( | ) { ( ( ) )
2 ( ( ) )
( ) }
k
q qT T T
k k k
k k
T T T
q qT T
k k k k
k k
Var f
y Φ I T TT M T Φ
Φ T TT M ψ
ψ TT M ψ
with 1
+ + .q
k k
k
n n
θM V I V I
If the limit of posterior mean
value w is taken for , we find that
1lim( )T
TT M y
1 1 1 1 1( ( ) )T T M M T T M T T M y
(19)
1 1 1 1lim ( ) ( )T T T
T TT M y T M T T M y
(20)
Combining results in (17), (19) and (20), we have
1
1 1 1
1 1 1 1 1
1
ˆˆ lim ( | )
( )
( ( ) )
k
q
k
k
T T T
qT T T
k k
k
w f E w
y
Φ T M T T M y
ψ M M T T M T T M y
(21)
and
1
1 1
1
1 1 1
1
1 1 1 1 1
1
lim ( | ) lim ( | )
= { ( )
2 ( )
( ( ) )
q
k
k
qT T
k k
k
qT T T
k k
k
qT T T
k k k k
k k
Var w Var f
y y
Φ T M T Φ
Φ T M T T M ψ
ψ M M T T M T T M ψ1
}q
where 1 1 1 1 1( ) ( ( ) )T Tn H λ I λ M M T T M T T M and
ˆ ( ( ))T n m y I H y
with 1
.q
k
k
m m
Hence,
k
1 1 1 1 1
lim ( | )= 2
( ( ) )
T T
k k k k kk k k
T T T
k k k k
Var f
y B C
ψ M M T T M T T M ψ
where kkB is a matrix corresponds to rows
1
1
1k
ww
m
to 1
k
ww
m
and columns 1
1
1k
ww
m
to 1
k
ww
m
of matrix T 1 1( )
T M T and kC
is a subvector of 1 1 1( )T T
k k T M T T M ψ with elements from
1
1
1k
ww
m
to 1
k
ww
m
. Based on these posterior covariances and
posterior means, we construct bayesian confidence intervals for
the overall function f and its components in (12). The
100(1 )% bayesian confidence interval for kf , k=1,...,q is
2
ˆ ( )k
k kj jjf z z d (22)
where jjd are diagonal elements of matrix lim |kVar f
D y .
C. Optimal smoothing parameters selection method
The smoothing parameters selection are crucial for the
performance of smoothing spline function estimates. A
selection method of the smoothing parameters k k ,
k=1,...,q for smoothing spline estimators in nonparametric
multivariable regression model using bayesian approach, that is
Generalized Maximum Likelihood (GML) is given as
1 1/
1GML( , , ) ( ( )) (det ( ( )))T n m
q n y I H λ y I H λ
where det+ is the product of the nonzero eigenvalues. The
values of 1, , q are optimal by minimizing
1GML( , , ).q
III. SIMULATION STUDY
In the simulations, we generated our data from the
nonparametric multivariable regression model (12) with
kiz i n , k=1,2; i=1,...,n, and the functions were set to be
13
1 1( ) 6.36zf z e and
6 11 6 4 3 10
2 2 2 2 2 2( ) 10 [ (1 ) (12,7)] 10 [ (1 ) (4,11)]f z z z Be z z Be
where ( , )Be p q is the Beta function. The simulation settings
were set to have three different sample sizes n = 50, 100, 200.
The random errors i were generated from the standard normal
distribution. GML method is used to choose smoothing
parameters for all simulations. The intervals must be
interpreted “across-the function”, rather than pointwise. The
number of data points at which the confidence interval cover
the true values of f1(z1), f2(z2) and f1(z1)+f1(z2) are recorded.
These numbers are then divided by the sample size to form the
coverage percentage of the intervals on design points. We
summarize these coverage percentage in Table 1.
Table 1.
Coverage Percentages of 90% and 95% Confidence Interval
in Simulation
function Coverage Percentages
n=50 n=100 n=200
0.05 f1(z1)+f1(z2
) 0.940 0.850 0.885
f1(z1) 0.720 0.770 0.755
f2(z2) 0.700 0.780 0.760
0.10 f1(z1)+f1(z2
) 0.900 0.850 0.885
f1(z1) 0.700 0.760 0.740
f2(z2) 0.700 0.770 0.755
The Third Basic Science International Conference - 2013 M28-4
In simulations, we note that these confidence intervals are
not in general pointwise confidence intervals. The coverage
will tend to be less than nominal where the true curve has sharp
peaks or kinks and more than nominal where the true curve is
smooth. If the users interpret them appropriately across the
function, they will have a reasonable feel for the overall
accuracy of the estimate. The readers may judge them from the
plotted confidence intervals overlaying the true function of the
psychological information that is conveyed by the intervals. In
Figure 1, confidence interval smoothing spline function for
f1(z1), f2(z2) and f1(z1)+f1(z2).
0.0 0.2 0.4 0.6 0.8 1.0
-4e
+0
5-3
e+
05
-2e
+0
5-1
e+
05
0e
+0
0
z1
fz1
0.0 0.2 0.4 0.6 0.8 1.0
-4e
+0
5-3
e+
05
-2e
+0
5-1
e+
05
0e
+0
0
z2
fz2
-6e+05 -4e+05 -2e+05 0e+00
-6e
+0
5-4
e+
05
-2e
+0
50
e+
00
f1+f2
y
Fig. 1. 95% Confidence interval smoothing spline
function for f1(z1), f2(z2) and f1(z1)+f2(z2) with n = 50
IV. CONCLUSION
Bayesian confidence intervals have good frequentist
properties which provided that the smoothing parameter has
been estimated properly. As the shape of the smoothing
parameters used in GML method is fixed, further study may
consider to use the smoothing parameter in the form of random
variables and to develop methods for testing hypothesis in
nonparametric multivariable regression model.
ACKNOWLEDGMENT
The first author would like to thanks BPS-Statistics
Indonesia for the Ph.D. grant through Human Resources
Development Project in cooperation with Sepuluh Nopember
Institute of Technology, Surabaya, Indonesia with contract
number: 19/KS/01-VII/2010.
REFERENCES
[1] J. F. Carriere, “Non-parametric confidence intervals of instantaneous
forward rates”, Insurance: Mathematics and Economics, vol. 26, pp.
193–202, 2000.
[2] T. Krivobokova, T. Kneib and G. Claeskens, “Simultaneous confidence
bands for penalized spline estimators”, Technical report, University
Gottingen, 2010.
[3] V. Mao and L. H. Zhao, “Free knot polynomial splines with confidence
intervals”, Journal of the Royal Statistical Society, series B, vol. 65, pp.
901-919, 2003.
[4] D. Nychka, “Bayesian confidence intervals for smoothing splines”,
Journal of the American Statistical Association, vol. 83, pp. 1134-1143,
1988.
[5] G. Wahba, “Bayesian Confidence Intervals for the cross-validated
smoothing spline”, Journal of the Royal Statistical Society, series B, vol.
45, pp. 133-150, 1983.
[6] Y. Wang and G. Wahba, “Bootstrap Confidence Intervals for Smoothing
Splines and Their Comparison to Bayesian Confidence Intervals”,
Journal of Statistical Computational and Simulation, vol. 51, pp. 263-
279, 1995.
[7] Y. Wang, Smoothing Splines Methods and applications, CRC Press
Taylor & Francis Group, California, USA. 2011.
[8] M. Wiesenfarth, T. Krivobokova and S. Klasen, “Simultaneous
Confidence Bands for Additive Models with Locally Adaptive Smoothed
Components and Heteroscedastic Errors”, Technical Report, Georg
August Universitat Gottingen, 2010.
[9] S. N. Wood and G. Marra, “Coverage Properties of Confidence Intervals
for Generalized Additive Model Components”, Research Report, No.
313, Department of Statistical Science, University College London, 2011.
[10] L. Yang, “Confidence Band for additive Regression Model”, Journal of
Data Science, vol. 6, pp. 207-217, 2008.
z1
z2
f2(z2)
f1(z1)
The Third Basic Science International Conference - 2013 M29-1
1Abstract— Risk modeling of Dengue hemorrhagic fever (DHF)
cases is framed by some factors, such as spatial heterogeneity,
uncertainty components (or random effects), DHF nested within
two levels, and spatiotemporal varying. Nested factor could
happen such as DHF nested to location as level 1 and location
nested to population as level 2. This study develops and analyzes
spatial convolution (Poisson-Lognormal) model using Bayesian
approach, called Bayesian Poisson-Lognormal 2-level (BP2L)
spatiotemporal. In this model, spatial terms are treated as
random effects factors (namely uncorrelated and correlated).
BP2L spatiotemporal is a complex model, so the parameter
estimation needs the computational intensive approach. It
requires mathematical manipulation such as full conditional
distribution form gathered from its joint posterior in order to
estimate those parameters through Gibbs sampler or Metropolis-
Hasting. The investigation result showed that full conditional
distribution of model is closed form. Gibbs sampler, therefore, is a
right method for estimating the parameters.
Index Terms— Bayesian, closed form, correlated, DHF, full
conditional distribution, Poisson-Lognormal, uncorrelated
I. INTRODUCTION
engue hemorrhagic fever (DHF) analysis based location
used for monitoring and intervention tool. DHF case is
affected by the spatial heterogeneity as covariate and
random effects [1]-[5] introduced a spatial convolution
(Poisson-Lognormal) model accommodating random effects
(uncorrelated and correlated) and covariate. This spatial
convolution model was applied by [6],[7] in 31 districts of
Surabaya DHF data on 2010 and shown realistic result.
In other deep study, DHF case varies not only spatially but
also temporally [8], so that convolution model has been
developed into a spatiotemporal model by adding temporal
trend and log relative risk using Bayesian approach since 2007
by [9]. DHF case is also hierarchically structured data, as
shown in [11]. It has been demonstrated that DHF case is
Mukhsar is PhD Student of Statistics Department Institut Teknologi
Sepuluh Nopember (ITS) Surabaya; e-mail:
Iriawan, N., is lecturer of Statistics Department Institut Teknologi Sepuluh
Nopember (ITS) Surabaya. He is also vice rector 3 of Institut Teknologi
Sepuluh Nopemner (ITS) Surabaya; e-mail: [email protected]
Ulama, B. S. S., is lecturer of Statistics Department Institut Teknologi
Sepuluh Nopemner (ITS) Surabaya. He has also a head of statitiscal
computation of Statistics Departmenet Institut Teknologi Sepuluh Nopemner
(ITS) Surabaya; e-mail: [email protected]
Sutikno, is lecturer of Statistics Department Institut Teknologi Sepuluh
Nopember (ITS) Surabaya; e-mail: [email protected]
Heri, K., is lecturer of Statistics Department Institut Teknologi Sepuluh
Nopember (ITS) Surabaya; e-mail: [email protected]
nested to district as level 1 and each district is nested to
Surabaya city as level 2 (or 2-level hierarchy).
The purpose of this study develops spatial convolution and
temporal model applied on 2-level hierarchical data by using
Bayesian approach, called Bayesian Poisson-Lognormal 2-level
(BP2L) spatiotemporal. BP2L spatiotemporal would have a
complex joint posterior of parameters model, so that parameter
estimation needs the computational intensive approach. One
way to solve the estimation is by constructing full conditional
distribution and employing Gibbs sampler or Metropolis-
Hasting algorithm. These algorithms require the appropriate
method for generating the parameters of model [10],[11].
When the full conditional distribution has closed form, the
Gibbs sampler is simpler be used. Otherwise, Metropolis-
Hasting is more appropriate [12]-[14]. The simplest way to
identify the closed-form of full conditional distribution is by
characterizing the pattern of functional form of Poisson
distribution, normal distribution, gamma distribution,
logarithmic functions, exponential functions, integrals, or
Taylor series. When Gibbs sampler is appropriate, WinBUGS
can be used to estimate these parameters [15],[16].
II. BAYESIAN POISSON-LOGNORMAL 2-LEVEL
SPATIOTEMPORAL
The most commonly encountered district count based model is
Poisson model. It would be suitable when there is a relatively
rare event of DHF in relatively large population in each district.
Suppose the DHF count sty is identically distributed Poisson
with parameter st . Poisson variability is influenced by st
that depends on district or location s and time t. Then, the
exploring BP2L spatiotemporal as described in section 1,
therefore, could be expressed as[9],
~ ( )st st sty Poisson (1)
With
T0
1
exp , 1, , , 1, , , 1,..., ,P
st st pst p s s z s zp
e x u v t t s S t T p P
where S is the number of locations, T is length of time
observation, P is the number of covariates, ste is an expected
count in district sth at time t
th, pstx is p
th covariate in district s
th
at time tth,
su is uncorrelated random effect at district sth, sv is
correlated random effect (CAR model) at district sth, zt is
trend temporal, and s zt is log relative risk. Likelihood and
Full Conditional Distribution Investigation of
Bayesian Poisson Lognormal 2-Level Spatiotemporal for
Analyzing DHF Risk
Mukhsar, Iriawan, N, Ulama, B. S. S, Sutikno, Kuswanto H
D
The Third Basic Science International Conference - 2013 M29-2
joint prior distribution of (1), therefore, are defined
respectively as,
1( ,..., )t Stp y y A B λ ,
(2)
0{ , , , , , , , , , }p s s s u vu v λ
T0
1
1 1
exp
!
ityP
st p pst s s z i zT S p
stt i
e x u v t t
Ay
T0
1 1 1
exp expT S P
st p pst s s z s zt s p
B e x u v t t
and
( )stp C D (3)
0( ) ( ) ( ) ( ) ( )p s u s vC p p p p u p v
( ) ( ) ( ) ( ) ( ) ( ).s u vD p p p p p p
Based on equation (2) and (3), joint posterior would be
1( ,..., ) ,t Stp y y E F G λ (4)
where
T0
1
1 1
exp
!
styP
st p pst s s z s zT S p
stt s
e x u v t t
Ey
T0
1 1 1
exp expT S P
st p pst s s z s zt s p
F e x u v t t
0( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( )p s u s v s u vG p p p p u p v p p p p p p
Definition 1. (Full conditional distribution) (Congdon,
2010). Suppose joint posterior of (4),
11
1
1 0
( ,..., ) ( )( ,..., ) ,
( ,..., ) ( )
( ,..., ) ( ) , { , , , , , , , , , }
t Stt St
t St
t St p s s s u v
p y y pp y y
p y y p d
p y y p u v
λ
λ λλ
λ λ λ
λ λ λ
then full conditional distribution for p is defined as
1 0
1
( ,..., , , , , , , , , , , )
[ .] ( ) ( ,..., ) ,
p t St p s s s u v
p p t St
p y y u v
p p y y
λ
and treats the other parameters exceptp , expressed as
p,
are constant.
Definition 2 (Closed form) (Hoff, 2009). Suppose that prior
of each parameter containing in λ following the standard
distribution as in Table 1, the full conditional distribution p
as an example, is written as 1[ .] ( ) ( ,..., ) ,p p t Stp p y y λ
would be closed form, if it can be rearranged to be a standard
distribution.
Based on Definition 1, prior distribution in Table 1, and joint
posterior (4), the full conditional distribution for each
parameter of model (1) can be created. Supposed that p is
treated as an example, the full conditional distribution would
be,
T T
1 1 1 11 1
. exp exp exp .
styT S S T S P
p st p pst st p psts t s pt s
e x e x H
(5)
21
exp22
pH
Equation (5) would be elaborated more deeply and it could be
represented as
T
1 1 1
1. exp ,
2
T S P
p st p pstt s p
y x J
(6)
2T
1 1 1
exp exp2
T S Pp
st p pstt s p
J e x
Taylor series around * 0p
could be employed to
approximate the T1
expP
p pstpx
[2], and found that
2
T T 2
1 1 1
1. exp 1 .
2
T S P
p st st pst p st pst pt s p
y e x e x L
(7)
1 1
exp
2
T S
stt s
e
L
Suppose,
T11
1 1 1
T S P
st st pstt s p
A y e x
and
2T
121 1 1
1 ,T S P
st pstt s p
A e x
then (7) can be written 2
11
212 11
12
2exp
21. exp .
22p p
A
A A
A
(9)
Based on the Definition 2, full conditional distribution for p
is closed form,
211 11
12 12
2 2, exp .p
A AN
A A
Full conditional distributions for the other parameters are also
closed form which can be created similar asp
, which are
listed in Table 2.
The Third Basic Science International Conference - 2013 M29-3
Corollary. Given BP2L spatiotemporal (1), if set of likelihood
(2) and prior (3) are following the assumptions in Table 1, then
its full conditional distributions are closed form.
III. CONCLUSIONS AND FUTURE RESEARCH
Full conditional distributions of BP2L spatiotemporal are
closed form. Gibbs sampler, therefore, would be used for
estimating the parameters. Further research for applying BP2L
spatiotemporal to Surabaya DHF data would be interesting.
ACKNOWLEGMENTS
This article is a part of Laboratory’s research grant and
doctoral research at Statistics Department of Institut Teknologi
Sepuluh Nopember (ITS), Surabaya, Indonesia, granted by
LPPM Institut Teknologi Sepuluh Nopember (ITS). We thank
Head of BPS and BMKG Surabaya city.
REFERENCES
[1] Ainsworth, L. M. and Dean, C. B.(2005). Approximate
Inference for Disease Mapping, Computational Statist.&
Data analysis, Elsevier, 50, 2552-2570,
DOI:10,1016/j.csda.2005.05.001.
[2] Chowell, G., Cazelles, B., Broutin, H. and Munayco, C.
V. (2011). The influence of geographic and climate
factors on the timing of dengue epidemics in Perú, 1994-
2008, BMC Infectious Disease, Mathematical and
Computational Modeling Sciences Center, School of
Human Evolution and Social Change, Arizona State
University, Tempe, USA
[3] Clark, J. S., and Gelfand, A. E (2005). Hierarchical
Modelling for the Environmental Sciences, Statistical
Methods and Application, Oxford University Press.
[4] Congdon, P. D. (2010). Applied Bayesian Hierarchical
Methods, Chapmann&Hall, CRC Press, UK,
QA279.5.C662010.
[5] Eckert, N., Parent, E., Belanger, L., and Garcia, S.
(2007). Hierarchical Bayesian Modeling for Spatial
Analysis of the Number of Avalance Occurrences at the
Scale of the Township, Journal of Cold Regions Science
and Technology, Elsevier, 97-112,
DOI:10.1016/j.coldregions.2007.01.008.
[6] Gelfand, A. E, Diggle, P. J., Fuentes, M., and Guttorp, P.
(2010). Handbook of Spatial Statistics , , Chapman &
Hall, UK, QA278.2.H3742010
[7] Ghosh, M., Natarajan, K., Waller, L. A., and Kim, D.
(1999). Hierarchical Bayes GLMs for the Analysis of
Spatial Data: An Application to Disease Mapping,
Journal of Statistics Planning Inference, Elsevier, 75,
305-318, DII:SO378-3758(98)001150-5.
[8] Hamada, M. S., Wilson, A. G., Reese, C. H., and Martz,
H. F. (2008). Bayesian Reliability, Springer,
DOI:10.1007/978-0-378-77950-8.
[9] Hoff, P. D. (2009). A First Course in Bayesian Statistical
Methods, Springer,DOI 10.1007/978-0-387-92407-6.
[10] Iriawan, N., Ulama, B. S. S., Sutikno, Heri, K. (2012).
Report of Laboratory Research, LPPM ITS, Surabaya.
[11] Lawson, B. A. (2008). Bayesian Disease Mapping:
Hierarchical Modeling in Spatial Epidemiology, CRC
Press, Chapman&Hall, RA792.5.L3872008.
[12] Li, N., Qian, G., and Huggins, R. (2002). A Random
Effects Model for Disease with Heterogeneous Rates of
Infection, Journal of Statistics Planning and Inference,
Elsevier.
[13] Neyens, T., Faes, C., and Molenberghs, G. (2011). A
Generalized Poisson Gamma Model for Spatially
Overdispersed Data, Journal of Spatio temporal
Epidemiology, Elsevier, 1-10,
DOI:10.1016/j.sste.2011.10.004.
[14] Ntzoufras, I. (2009). Bayesian Modeling Using
WinBUGS, John Wiley&Sons, QA279.5.N892009, New
Jersey.
[15] Maiti, T. (1998). Hierarchical Bayes Estimation of
Mortality Rates for Disease Mapping, Journal of
Statistical Planning and Inference, Elsevier, 339-348,
PII:SO378-3758(97)00165-1.
[16] Mukhsar, Iriawan N., Ulama, B. S. S., Sutikno,
Kuswanto, H. (2012). Spatial Bayesian Poisson-
Lognormal Analysis of Dengue Relative Risk Incidence in
Surabaya on 2010, Proccedings of International
Conference Mathematics Statistics and Its Application,
ITS, Surabaya.
[17] Royle, J. A. and Dorazio, R. M. (2008). Hierarchical
Modeling and Inference in Ecology, The Analysis of
Data from Populations, Metapopulations and
Communities, Elsevier, Academic Press.
Table 1. Prior distribution of BP2L spatiotemporal
0( ) ~ ()p flat
( ) ~ (0, )p N
1 2( ) ~ ( , )up G c c
1 2( ) ~ ( , )vp G d d
1 2( ) ~ ( , )p G a a
( ) ~ (0, )pp N
1 2( ) ~ ( , )p G e e
( ) 1( ) ~ ,
S
jj s
ss s
p ND D
1 2( ) ~ ( , )p G b b
( ) 1( ) ~ ,
S
jj s
ss v s
v
p v ND D
The Third Basic Science International Conference - 2013 M29-4
Table 2. Full conditional distributions of BP2L spatiotemporal
0 0 01 1
exp exp( ) log .T S
st stt s
y e K
211 11
12 12
2T T
11 121 1 1 1 1 1
2 2, exp ,
, 1 .
p
T S P T S P
st st pst st pstt s p t s p
A AN
A A
A y e x A e x
211 11
12 12
11 121 1 1 1
2 2~ , exp ,
, 1 .
Su us u
T S T S
st st u stt s t s
B Bu N
B B
B y e B e
211 11
2
12 12
211 12
1 1 ( ) 1 1
2 2~ , exp ,
, .
Sv v
s v s
T S S T S
st st v j v st v st s j s t s
C Cv N D
C C
C y e v C e D
211 11
12 12
11 121 1 1 1
2 2, exp ,
, 1 .T S T S
st st stt s t s
F FN
F F
F y e F e
2
22 ( )11 11
12 12
211 12
1 1 ( ) 1 1
2 21~ , exp ,
2
, .
S
S jj s
ss s
T S S T S
st st j st st s j s t s
G GN
G D GD
G y e G e D
The Third Basic Science International Conference - 2013 M30-1
1Abstract-Migration is the process of moving people from one
region to another. There are two aspects that follow the process,
those are individuals and regions. The individual data or the
micro data requires specific modeling to the individual
characteristic related to the decision to migrate. While the region
data or macro data requires different modeling to characterize
the region, as the origin and the destination of migration. The
population mobility become more complex at district/city levels
compared to inter-provincial or even international due to the
completeness data. The East Java Province is known as the
province that send migrants to other provinces in Indonesia and
even internationally. Several theories reveals that economic is one
of the dominant factors in migration, but it does not comply in
this cases. This province can be categories as strong economics as
Jakarta, but out migrations from East Java is still high. The high
economic growth in East Java province cannot resist the out
migration flows. The imbalance of economic growth evenly among
districts/cities should be one of major factors that have to be
overviewed closely.
Index Terms-East Java, Migration, Models
I. INTRODUCTION
Migration as a population problems, hold an important role
especially after globalization, technological advances, and the
ease of transportation access. Progress in some fields, like
health and technology, makes easy to control the quantity of
natural population by pressing a number of fertility and
mortality, but it does not apply to control the migration. From
the perspective of the individual, of course, it is more
advantageous because it provides more opportunities to make
choices for improving their living standards. Those facts, on
the other hand, are believed to be as a problem by the
government as policy makers. The migration consequences that
out of control, can affect many sectors such as economic,
social, educational, health, and others. An understanding of
migration patterns become very important in the framework of
development goals that cannot be detached from the
population problem.
Preatin is student at Department of Statistics, Institut Teknologi Sepuluh
Nopember - Surabaya, East Java, Indonesia (corresponding author to e-mail:
Nur Iriawan is Vice Rector for Resources and Organization, and also as
senior lecturer at Institut Teknologi Sepuluh Nopember - Surabaya, East Java,
Indonesia (e-mail: [email protected]).
Ismaini Zain is lecturer at Institut Teknologi Sepuluh Nopember - Surabaya,
East Java, Indonesia (e-mail: [email protected]).
Wendy Hartanto is PCC and Deputy for Population Management National
Family Planning Coordination Board (BKKBN), Jakarta, Indonesia (email :
In developing countries, including Indonesia, understanding
of the migration phenomenon becomes more limited due to
availability of data. The registration of resident has not done
continuously well mainly related to the resident mobility.
Analyzing to the migration phenomenon, therefore, is fully
relying on the results of 10 yearly population censuses. The
population mobility become more complex at district/city levels
compared to inter-provincial or even international due to lack
of the completeness data.
Several theories of migration have been developed based on
some point of views of different disciplines such as sociology,
micro or macro economics, geography, and interdisciplinary
science. Figure 1 describes the scheme theory of migration
from some discipline of sciences [4].
Figure 1. The Scheme Theories of Migration
Many discipline of sciences interested in developing
migration model. It is because migrations are a complex
phenomenon that involves many dimensions. It requires a
comprehensive understanding which is not limited to particular
disciplines. Multidisciplinary modeling approach couple with
the right chosen variables would be more beneficial than just
using any particular theory approach [2]. Bijak [2] had been
improved in [4] describes the topological relationship of some
of the methods and models of migration as in Figure 2.
On the View of the Modeling Interregional Migration in
East Java: Selected Models
Preatin, Nur Iriawan, Ismaini Zain, Wendy Hartanto
The Third Basic Science International Conference - 2013 M30-2
Figure 2 Typology of Migration Methods and Models
There are two aspects that follow the process, those are
individuals and regions. The individual data or the micro data
requires specific modeling to the individual characteristic
related to the decision to migrate. While the region data or
macro data requires different modeling to characterize the
region, as the origin and the destination of migration. Figure 3
shows separation some models that are used to elaborate
migration viewed from the availability of data.
Figure 3. Separation of Selected Migration Models
II. MICRO MODELS
A. Logistic Model
Several studies using logistic models include [14], [18], and
[19]. McCullagh and Nelder [14] demonstrated logistic models
as a generally included in the model for binary scale responses
with log link function. The general form of logistic models as:
0 1 1log ...
1p px x
or
0 1 1
0 1 1
exp ...
1 exp ...
p p
p p
x x
x x
. (1)
Three-level logistic regression model with Bayesian
approaches had been used to modeling migration in Thailand
[11]. The model is used to see the influence of individual
factors, region, and time for individual decisions to migrate.
This approach had only succeeded to see the individual
decision to migrate is significant or not, while the regional
analysis had not been performed. Based on the data used in this
model, it would be very hard in preparation for analysis. It is
due to the difficulty to have the entire population data. Using
logistic models on individual data migration, on the other hand,
will involve migrants and non-migrants. Indonesia which still
relies on census data for the analysis of migrations, therefore,
need the use of computational intensive approaches due to the
involving large data.
B. Event History Analysis
Migration studies using event history analysis have been
began, among others [12], [7]-[10], and [38]. Migration is one
of the events that occurred on the individual demographics
such as change of marital status, changes in the level of
education, type of economic activity and other changes.
Migration in event history analysis is historically one dwelling,
which is focused to a time between switching [2]. Courgeau
[8], modeled the migration opportunities (transition) using
continuous time approaches:
, ,
1
0
( ), ( )
, , , ( ), ( )lim
a a a
i j k i j
a a a a a a
k k k k i j
dt
m t x t y t
P T t dt I j T t I i x t y t
dt
(2)
This Model elaborated some variables as a is an individual
having duration of stay Tka, k-1 is the number of migrate by
individual a, Ika is a random variable for region, individual
characteristics a is xia , and characteristics of area destination j
is yia. This model requires a special survey to see the migration
history of each individual during every individual lifetime.
C. Schedule Model
Figure 4 shows migration patterns according to age. Its
graduation was changed by a scheduled model, which is
defined as a sum of four components:
Migration
The Third Basic Science International Conference - 2013 M30-3
1. Pre-labor force, a single negative exponential curve with its
rate of decent 𝛼1.
2. Labor-force, a left skewed unimodal curve with mean age μ2,
rate of ascent λ2, and rate of decent 𝛼2.
3. Post-labor force, an almost bell shaped curve, with mean age
μ3, rate of ascent λ3, and rate of decent 𝛼3.
4. Post-retirement peak, exponential curve with rate of ascent
λ4.
5. Constant c.
α1 = rate of descent of pre-labor force component xj = low peak
λ2 = rate of ascent of labor force component xh = high peak
α2 = rate of descent of labor force component xr = retirement peak
λ3 = rate of ascent of post-labor force component X = labor force shift
α3 = rate of descent of post-labor force component A = parental shift
c = Constant B = Jump
Figure 4 Migration Model Schedule
Those four components would build the equation that
defines as:
1 1 2 2 2 2 2
3 3 3 3 3 4 4
( ) exp( ) exp{ ( ) exp[ ( )]}
exp{ ( ) exp[ ( )]} exp( )
M x a a x x
a x x a x c
(3)
Equation (3) is a full model with 13 parameters. Based on
comparative analysis of over 500 profile scheduled model done
in [25], the majority profile were match with a simpler model
containing 7 parameters that consist of two components and
constants.
III. MACRO MODELS
A. Gravity Model
Gravity models are widely used for the analysis of macro-
level data, mainly if the availability data are in the form of flow
from an origin to a destination migration. Bijak [4] was defined
the initial assumption of this model by employing Newton's
Gravity Law. That is migration between regions i and j is
proportional to the product of the mass (size of population)
areas of origin and destination (Pi and Pj) and inversely
proportional to the distance between the two regions (dij). The
mathematical expression of this model is:
.i j
ij
ij
PPm G
d (4)
This is a continuous model which evolves not only variables of
population size but also socio-economic variables and others.
Distance variable is also experienced growth. It would involve
travel time that related with the availability of transportation.
To include this variable in the model, the migration data needs
to be performed as the origin-destination matrices, so that the
interaction between the regions would be more perceptible.
B. Spatial Autoregressive (SAR)
SAR models had been used by [37] with mathematical
models:
1o o d d w w n o o d dy W y W y W y X X d
(5)
where the dependence is based on the origin and destination.
Weighting matrix is calculated by using Kronecker
multiplication result (origin-base), (destination-base), and
(origin-to-destination-base). SAR model is more profitable
than the use of gravity models when the migration data in the
form of origin-destination contains some missing values.
C. Multinomial Logit Model
Multinomial Logit Model was developed by adding the
spatial competition variable to see the competitiveness of the
migration destination area [16]. The model is mathematically
expressed as:
1
1
exp( ) 1; ,
1exp( )
n Kij jn k
ij jJn k kj
ij j
i
V c WP c k j
k dV c
(6)
Pijn is the opportunity to move from the area of origin i to
destination j, Vijn is the value obtained from the displacement of
the area i to area j, cj is competition variable for regional j, θ is
parameter for the competition variable, Wk is the size of region
k, dkj is a distance between region k and j, where j, k=1,2,…,K.
D. Poisson and Negative Binomial Regression
Poisson regression is used to model migration by employing
origin and destination region variables. Migration data is
assumed to be Poisson distribution, yi|β ~ Pois (μi); for i = 1,
2,..., n. Mean (μi) would be connected with the independent
variable using the log link function, log( ) T
i ix . It is
assumed that there is a linear relationship between independent
variable and log mean. Poisson regression is not appropriate
for the data having variance not equal to the mean. It is
because if these conditions are happened then there is over-
dispersion, and Poisson-Gamma Mixture Model would be an
alternative approaches to overcome. When the data follow
, ( );i i i jy Pois and , ( , )i k v Gamma k v ,
then the marginal distribution of y would be Negative Binomial
[17].
IV. CONCLUSION
Modeling migration must be adapted to the purpose of
research and the availability of data. For interregional
migration in East Java having limited data requires the
The Third Basic Science International Conference - 2013 M30-4
selection of an appropriate model. Development of existing
models to fulfill the analysis needs is necessary, especially when
the data is limited. The models as gravity models, SAR,
multinomial logit models, and negative binomial regression are
appropriate to be employed to model the migration people in
East Java. Bayesian approach, on the other hand, is suggested
to be employed, because it would be more flexible as data
driven approaches, but it requires computational intensive
capabilities.
REFERENCES
[1] Assuncao, R.M., Schmertmann, C.P., Potter, J.E., and Cavenaghi, S.M.,
“Emprical Bayes Estimation of Demographic Schedules for Small
Areas”, Demography, Vol.2, No.3, pp. 537-558, 2005.
[2] Bijak, J., “Forecasting International Migration: Selected Theories,
Models, and Methods”, Central European Forum For Migration Research
(CEFMR) Working Paper No. 04, Warsaw, Poland, 2006.
[3] Bijak, J., Bayesian methods in international migration forecasting in
“International Migration in Europe: Data, Models and Estimates”, J.
Raymer and F. Willekens, Chichester, GB, John Wiley, pp. 255-281,
2008.
[4] Bijak, J., “Forecasting International Migration in Europe: A Bayesian
View”, Springer, London, 2011.
[5] Butzer, R., Mundlak, Y., and Larson, D.F., “Intersectoral Migration in
Southeast Asia: Evidence from Indonesia, Thailand, and the Philippines”,
Journal of Agricultural and Applied Economics, Vol.35, pp.105-117,
2003.
[6] Congdon, P., “A Bayesian Approach to Prediction Using the Gravity
Model, with an Aplication to Patient Flow Modeling”, Geographical
Analysis, Vol. 32, No.3, pp.205-224, 2000.
[7] Courgeau, D., “Interaction between Spatial Mobility, Family and Career
Life Cycle: A French Survey”, European Sociological Review, Vol.1,
No.2, pp.139–162, 1985.
[8] Courgeau, D., “Migration theories and behavioural models”,
International Journal of Population Geography, vol.1, No.1, pp.19–27,
1995.
[9] Courgeau, D., “From the Macro-Micro Opposition to Multilevel Analysis
in Demography” in Methodology and Epistemology of Multilevel
Analysis, D. Courgeau, Dordrecht, Kluwer, 2003.
[10] Courgeau, D. and Lelièvre, E., Event history analysis in demography.
Oxford University Press, Oxford, 1992.
[11] Garip, F. and Western, B., Model Comparison and Simulation for
Hierarchical Models: Analyzing Rural-Urban Migration in Thailand,
Weatherhead Center for International Affairs (WCFIA) Working Paper
No. 0056, Harvard University, Cambridge, 2008.
[12] Ginsberg, R.B., “Probability Models of Residence Histories: Analysis of
Times between Moves”, in Population Mobility and Residential Change,
Clark, W.A.V. and Moore, E.G., Northwestern University, Evanston, IL,
1978.
[13] Gullickson, A., Multiregional Probabilistic Forecasting, presented in
“The Young Scientists Summer Program Midsummer Workshop,
International Institute for Applied Systems Analysis”, Vienna-Austria,
July 2001, printed at www.demog.berkeley.edu/~aarong/PAPERS/
gullick_iiasa_stochmig.pdf
[14] McCullagh, P. and Nelder, J. , Generalized Linear Models, Second
Edition, Chapman and Ppl, Boca Raton, 1989.
[15] Muhidin, S, The Population of Indonesia, Rozenberg Publishers,
Amserdam, 2002.
[16] Pellegrini, P.A. and Fotheringham, A.S., “Intermetropolitan Migration
and Hierarchical Destination Choice: A Disaggregate Analysis from the
US Public Use Microdata Samples”, Environment and Planning A,
Vol.31, pp.1093-1118, 1999.
[17] Perrakis, K, Karlis, D., Cools, M., Janssens, D., Vanhoof, K. And Wets,
G., “A Bayesian Approach for Modeling Origin-Destination Matrices”,
Trasportation Research part A: Policy and Practice, Vol. 46, Issue 1,
pp.200-212, 2012.
[18] Phouxay, K., Malmberg, G., and Tollefsen, A., “Internal Migration and
Socio-Economic Change in Laos”, Migration Letters, Vol.7, No.1, pp.
91-104,2010.
[19] Poncet, S., “Provincial Migration Dynamics in China: Borders Costs and
Economic Motivations”, Regional Science and Urban Economics,
Vol.36, pp.385-398, 2006.
[20] Raymer, J.,” The estimation of international migration flows: A general
technique focused on the origin-destination association structure”,
Environment and Planning A, Vol.39, No.4, pp.985-995,2007.
doi:10.1068/a38264.
[21] Rogers, A., “Model Migration Schedules: A Aplication Using Data for
The Soviet Union”, Canadian Studies in Population, Vol.5, pp.85-98,
Canada,1978.
[22] Rogers, A.,” Parameterized multistate population dynamics and
projections”, Journal of the American Statistical Association, Vol.81,
No.393, pp. 48-61, 1986.
[23] Rogers, A., “Age patterns of elderly migration: An international
comparison”, Demography, Vol.25, No.3, pp355-370,1988.
[24] Rogers, A., Demographic Modeling of the Geography of Migration and
Population : A Multiregional Perspective, Population Program Working
Paper No.02, Institute of Behavioral Science, University of Colorado,
Boulder,2007.
[25] Rogers, A. and Castro, L.J., “ What the Age Composition of Migrants
Can Tell Us”, Population Bulletin of the United Nations, No. 15, pp. 66-
79,1983.
[26] Rogers, A. and Little, J.S., “Parameterizing age patterns of demographic
rates with the multiexponential model schedule”, Mathematical
Population Studies, ratesol.4., No.3, pp. 175-195,1994.
[27] Rogers, A. and Watkins, J.F., “General versus elderly interstate migration
and population redistribution in the United States”, Research on Aging,
Vol.9, No.4, pp.483-529,1987.
[28] Rogers, A., and Raymer, J., “The Spatial Focus of U.S. Interstate
Migration Flows”, International Journal of Population Geography,
Vol.4, pp.63-80,1998.
[29] Rogers, A., and Raymer, J., “Estimating the regional migration patterns
of the foreign-born population in the United States: 1950-1990”,
Mathematical Population Studies, Vol. 7, No.3, pp. 181-216, 1999.
[30] Rogers, A., and Raymer, J., “Fitting observed demographic rates with the
multiexponential model schedule: An assessment of two estimation
programs”, Review of Urban and Regional Development Studies,
Vol.11, No.1, pp.1-10, 1999a. doi:10.1111/1467-940X.00001.
[31] Rogers, A., and Raymer, J., “Using Age and Spatial Flow Structures in
the Indirect Estimation of Migration Streams”, Demography, Vol.44,
No.2, pp.199-223, 2007.
[32] Rogers, A., Little, J., and Raymer, J., The Indirect Estimation of
Migration, Springer, London, 2010.
[33] Rogers, A., Willekens, F., and Raymer, J., “Imposing age and spatial
structures on inadequate migration flow data sets”, The Professional
Geographer, Vol. 55, No.1, pp. 56-69, 2003. doi:10.1111/0033-0124.
01052
[34] Safrida, S.B.M., Siregar, H., and Harianto, “Dampak Kebijakan Migrasi
Internal terhadap Perilaku Pasar Kerja di Indonesia”, IPB E-Jurnal,
2008, printed at http://repository.ipb.ac.id/handle/123456789/45432.
[35] Smith, P.W.F., Raymer, J., and Giulietti, C., “Combining available
migration data in England to study economic activity flows over time”,
Journal of the Royal Statistical Society: Series A (Statistics in Society),
Vo. 173, No.4, pp. 733-753, 2010. doi:10.1111/j.1467-985X.2009.
00630.x.
[36] Tsegai, D. And Le, B.Q., District-level Spatial Analysis of Migration
Flows in Ghana: Determinants and Implications for Policy, Zentrum fur
Entwicklungforschung Discussion Papers on Development Policy No.
144, Universiy of Bonn, Germany, 2010.
[37] Tsutsumi, M. and Tamesue, K.,” Intraregional Flow Problem in Spatial
Econometric Models for Origin-Destination Flows”, Procedia Social and
Behavioral Sciences, Vol.21, pp.184-192, 2011.
[38] Van Imhoff, E., and Post, W.,” Microsimulation methods for population
projection”, Population–E, Vol.10, No.1, pp. 97–138, 1998. [39] Wilson, T., “Model Migration Schedules Incorporating Student
Migration Peaks”, Demographic Research, Vol 23, No. 8, pp.191-222,
2010.
The Third Basic Science International Conference - 2013
M31-1
Abstract— This article explores the use of generalized
linear model (GLM) in modelling AIDS cases in Indonesia.
The analysis was based on longitudinal cumulative data of
32 provinces during the period 2004-2011. Year, group of
provinces, and prevalence were proposed to explain
variability of AIDS cases. Some models are proposed,
i.e.GLM with normal link function for cases and log-
natural cases (ln Cases), and gamma link function. AIC
and deviance were used as goodness of fit criteria of the
model. The best model is linear model with ln cases as
dependent variable and Year and Group as independent
variables. This model can explain 83 % variablity of the
data According to the model, in 2020 there will be
247,037AIDS cases in Indonesia.
Index Terms— AIDS cases, GLM
I. INTRODUCTION
ince the first detection of Acquired ImmunoDeficiency
Syndrom (AIDS) in Indonesia in 1985, the amount of
peoples with AIDS (AIDS cases) has been increasing with
year. In 2011, AIDS cases in Indonesia became more than
29.000 [1]. There is the necessity to estimate AIDS cases for
several needs, i.e. drug stock, and medical attention for HIV
infected and AIDS patients. Estimation is usually done through
determining growth model for AIDS cases.
Several techniques had been applied for modelling the
growth of AIDS cases. The study by [2] estimated cumulative
AIDS cases in Indonesia with EM algorithm using the amount
of people infected by HIV with assumption of incubation
periods 5-10 years. Previously, the author [3] has developed a
model of AIDS cases in Belgium with GLM, where the annual
AIDS cases is assumed to be Poisson’s process. Ministry of
Health of Indonesia also published the estimated of AIDS cases
in Indonesia every year. These estimations use single times
series of national AIDS cases.
AIDS in Indonesia spreads differently in 32 provinces. Only
province of West Sulawesi doesn’t have AIDS cases until the
end of 2011. In 2011, some provinces have more than 1000
cases and rapidly have been growing since 1985. On the other
hand, in some provinces AIDS cases grow slowly and only
have less than 100. At least there are three groups of provinces
according to the growth of AIDS cases. The first is group of
H. Hanum is Senior Lecture in Statistics, Department of Mathematics,
FMIPA, Sriwijaya University (phone: +62711 580765; fax: +62711 580059; e-
mail: linhanum@ yahoo.com.au). She is now studying for her PhD in Statistics
at School of Graduate Studies, Bogor Agricultural University
provinces with high growth. These provinces have AIDS cases
more than 1000 in 2011. While the last group has provinces
with AIDS
cases less than 100. The longitudinal data for 32 provinces is
shown in Fig 1.
Fig. 1. Plot of AIDS cases in 32 Provinces of Indonesia Years
2004 - 2011
Availability of data for AIDS cases for each province
becomes the advantage for modelling. The growth model can
be built based on longitudinal data of provinces. It is also
possible to build some alternative models including advanced
model.
Problem statement
Some model can be proposed for estimating AIDS cases in
Indonesia. Firstly the model may be built without grouping the
provinces then compares with grouping model. Secondly,
considering the growth of AIDS cases, the model may be
nonlinear, according previous research its exponential. This is
the reason of choosing between normal or gamma link
function. What is the real growth type of AIDS in Indonesia.
Applying those models for Indonesian AIDS cases will
answer these questions
1) Does grouping infuence the goodnes of the model?
2) Which is the real growth model: linear or exponensial?
3) Does GLM using normal link function with dependent
variable ln cases give similar model with GLM using gamma
link function with cases as dependent variable?
II. MATERIAL AND METHOD
A. Material
1. Longitudinal data of AIDS cases in Indonesia is
observation of 32 provinces for years 2004-2011.
Generalized Linear Model for Estimating AIDS Cases in
Indonesia
Herlina Hanum
S
The Third Basic Science International Conference - 2013
M31-2
As mentioned before, based on growth type (see
Fig. 1), the provinces can be divided at least into 3
groups. The first group for high growth of AIDS
cases with more than 1000 cases in 2011. This
group consists of Papua, Jakarta, East Java, West
Java, Bali, Central Java, and West Kalimantan
provinces. The second group consists of provinces
with moderate growth. The provinces included in
this group are South Sulawesi, Riau, Yogyakarta,
North Sumatera, West Sumatera, Banten, Riau
Archipelago, North Sulawesi, East Nusa Tenggara,
Jambi, South Sumatera, West Nusa Tenggara,
Jambi , and Bangka-Belitung. The rest provinces,
which have less than 100 cases in 2011, become the
member of the third group.
B. Method
In order to answer the questions above, we propose some
model to be analyzed. These model are
1. General linear model for Indonesia the provinces
with normal link function for
Y = Xβ + ε
with Y is the AIDS cases as defendent variable, X
the matrix consists of vector 1 and year of
observation for ungroup model.
2. Adding group as independent variable to ungroup
model .
3. Exponensial model ln Y = Xβ + ε, that is GLM with
normal link funtion of ln Y. With and without group
as independent variable.
4. GLM model using gamma link function with AIDS
cases as dependent variable, and year and group as
independent variables.
Goodness of fit of the model measures by Akaike
Information Criteria (AIC) for GLM. For each GLM model
AIC is
where is maximized model log likelihood and p is the
number of explanatory variables (including the constant) [4].
The second criteria is deviance. According to [4] deviance is
the most useful category of residual for GLM and also the
most general form. This criteria likelihood ratio statistic
comparing a proposed model specification relative to saturated
model. Deviance is
Where is likelihood for proposed model, and for
saturated model [6].
III. RESULT
The data were analyzed using SPSS 18. GLM for AIDS
cases with year as single covariate using linear link function,
has Akaike’s Information Criteria (AIC) 4325.084. Adding
Group to this model reduced AIC to 4196.56. It means Group
make the linear model has better fit to the data.
However, these AIC values are very large compared with
the AIC = 672.729 of linear model with ln Cases as dependent
variable. This situation is accepted since the data do not meet
the assumption of homoscedasticity. Although the covariates
are significant in chi-squares test, it may be a false conclusion
due to the violent of the assumption. Logarithmic
transformation of Cases overcomes this problem.
TABEL 1.
DEVIANCE AND AIC VALUES OF PROPOSED MODEL FOR AIDS
CASES
Model Deviance AIC
Y = f(year) 1969E8 4325,084
Y = f(year, group) 1201E8 4196,560
Ln Y = f (year) 1056,46 1121,29
Ln Y = f(year, group) 191,710 672,729
Ln Y = f(year, group,
prev)
187,83 666,32
Gamma, Y = f(year,
group)
160,005 2938,691
Another variable that may influence the growth of AIDS
cases in Indonesia is the population of each province. This
variable is represented by prevalence of AIDS. Adding this
variable into last models didn’t make it has better fit. So the
population of province does not contribute to AIDS cases in
that province.
Logically, linear model with ln Cases as dependent variable
similar with GLM using Cases as dependent variable with log
link function. Do they give similar goodness of fit ? In fact the
second model has AIC = 2938,691, much larger than the one
of first model. It means the first model is the better one. On
the other hand, another goodness of fit criteria i.e deviance
leads to conclusion that Gamma link function as better model
since it has less values.
IV. DISCUSSION
In this article, the grouping of provinces significantly
influences the goodness of model. Dividing the 32 provinces
into 3 groups is subjective. It is only based on the number of
AIDS Cases in 2011. There may be another grouping that can
give better models.
Choosing two competing GLM model based on deviance
and AIC is little bit confusing. Since both of these criteria lead
to better model is the one with smaller value. Considering AIC
is negative of 2log likelihood of proposed model, so smaller
value of log likelihood will gives greater AIC. While deviance
measure the distance of 2 likelihood. The closer likelihood of
proposed model to the one of saturated model, the smaller the
value of deviance.
Here deviance of first model (191) larger than that of the
second model (160). But the difference is not big enough to
certain that GLM with gamma link function is better model
compare with the difference of AIC of both model. Parameters
estimate for both model are little bit similar. They yields
The Third Basic Science International Conference - 2013
M31-3
almost similar prediction. Furthermore, in model selection, the
better model is the simpler. These facts lead to select linear
model of ln Cases for estimating AIDS Cases in Indonesia. In
addition, linear model has another advantage. That is
percentage of variation of AIDS Cases that explain by the
model which represent by R2. The selected model
Ln Cases = -748.613 + 0.378 Year – 2.606 group
has R2 adjusted 0.829. Which can be simply interpreted as
82,9 % variances in Cases can be explained by the exponent of
the model. This model gives different growth for each group.
According to this model, in 2020 there will be 228890 AIDS
cases in first group, 16899 in second group, and 1248 in last
group. Totally, there will be 247037 cases in Indonesia.
It maybe interesting to model each group separately. The
result is both linear and exponential models of AIDS cases with
year as single independent variable didn’t good enough to
explain AIDS cases in each group. They only have R2
adj less
than 50%. So using whole provinces data is more useful.
As comparison, using single series of cumulative Indonesian
AIDS cases, the growth model is linear.
Cases = -7738969 + 3862,3 Year
With R-Sq(adj) = 98,3%. This model is very good fit the
cumulative data. But it cannot explain the variability growth of
AIDS cases in provinces. Its only useful for estimating
nationally AIDS cases.
Some authors i.e [5] and [7] suggest Generalized
Estimating Equations(GEE) for longitudinal data. It will yield
better model if there is correlation between observations in a
subject, in this case is province. Unless the result is the same
with the one of GLM. However it is better to try in the next
time.
V. CONCLUSION
Some conclusions can be derived. Firstly, grouping the
provinces is necessary. Since it explain some variation in
AIDS Cases for some group of provinces. Secondly, AIDS
cases has Exponential growth model. The best model for
AIDS Cases in Indonesia based on longitudinal data is
Ln Cases = -748 + 378 year – 2.6 Group.
REFERENCES
[1] Directorate General CDC & Environmental Health, Ministry of Health,
Republic of Indonesia, Cases of HIV/AIDS in Indonesia. Report. Jakarta:
Ministry of Health, 2012.
[2] H. Hanum, “Studi simulasi algoritma EM dalam pendugaan kasus
infeksi HIV,” M.S. Thesis, Dept. Applied Statistics., Bogor Agricultural
Univ., Bogor, Indonesia, 1996.
[3] S. Wood, Generalized Linear Models. UK: University of Bath,1993.
[4] J. Gill, Generalized Linear Models: A Unified Approach, Series
Number: 07-134. California: Sage Publication, 2001.
[5] J.W Hardin and J.M. Hilbe, Generalized Estimating Equations. Boca
Raton, Florida: Chapman & Halls CRC Press, 2003.
[6] A.J. Dobson, An introduction to Generalized Linear Models. 2nd ed.
Boca Rton, FL: Chapman & Hall/CRC, 2002.
[7] Liang, K.-Y. and S.L. Zeger, Longitudinal data analysis using
generalized linear models. Biometrika, 73, 13-22, 1986.
The Third Basic Science International Conference - 2013 M33-1
I INTRODUCTION
EVERAL recent papers explain methods to model teaching
quality. For example paper by Ahmed et al. (2010) and
Barone et al. (2010). We have published several papers to
explain how to determine teaching quality of lecturer based on
questiner (e.g. Setiawan & Parhusip (2011a), Setiawan &
Parhusip (2011b) and Parhusip & Setiawan (2011). Related
paper is also presented in Setiawan (2011a) that can be
considered related to this paper. It is used binomial models
for answer of every item in the questioner. In this paper, it is
explained how to determine teaching quality of lecturer based
on questioner using objective Bayesian and multinomial
models.
II THEORY
Bayesian inference is often critized for its reliance on prior
distributions whore choice influences the conclusions. In
particular, in testing theory the necessity of assigning prior
probabilities to the two hypotheses appears awkward. The
objective Bayesian approach overcomes this criticism by an
objective choice assumed model and the available data. In this
paper we propose an objective Bayesian to analyze data of
questioner using multinomial distribution and objective
Bayesian methods.
We consider x = ( x1, x2, ...., xm ) as answer of items in a
questioner that has m questions (items) where xi is the number
of respondent that gives skor 1, 2 or 3 for the i-th questions.
Variable xi = ( xi1, xi2, xi3) can be considered as a multinomial
distribution with parameter n and p = ( p1, p2, p3). In this case
n is the number of respondent and pi is the proportion of
respondent that give scor i where i = 1, 2, 3. The probability
density function of xi = ( xi1, xi2, xi3) is
321
321
321
321321,,
)),,(|),,(( iii xxx
iii
iii pppxxx
npppxxxf
where xi1, xi2, xi3 = 0, 1, 2, ...., n, xi1 + xi2 + xi3 = n,
0 < p1, p2, p3 < 1 dan p1 + p2 + p3 = 1. The Fisher information
can be computed to be
)1(
)1(
1
1)1(
)1(
),(
212
1
21
21211
1
21
ppp
pn
pp
n
pp
n
ppp
pn
ppI
and the reference prior is given by
Adi Setiawan is a lecturer at Department of Mathematics, Faculty of
Science and Mathematics, Satya Wacana Christian University Jl. Diponegoro
52-60 Salatiga 50711 (corresponding author to provide e-mail:
12
1
3
12
1
2
12
1
1
2/1
321
32111
1),,()(
ppp
ppppppp
.
Then, the reference prior is the Dirichlet( ½, ½, ½ )-
distribution. The posterior density function of p = ( p1, p2, p3 )
given x = ( x1, x2, x3 ) is
)),,(|),,(( 3213212 iii xxxppp
)),,(|),,((),,( 3213213211 pppxxxfppp iii
321
321
12
1
3
12
1
2
12
1
1iii xxx
pppppp
12
1
3
12
1
2
12
1
1321
iii xxxppp
.
Thus, the posterior 3( p | xi ) is Dirichlet( xi1 + ½, xi2 + ½,
xi3 + ½ )-distribution. The quotient of the density of xi =
( xi1, xi2, xi3) for two parameter values p = ( p1, p2, p3 ) and
q = ( q1, q2, q3 ) is given by
321
321
321
321
321
321
,,
,,
)|(
)|(
iii
iii
xxx
iii
xxx
iii
i
i
qqqxxx
n
pppxxx
n
qxf
pxf
and
3
33
2
22
2
11 lnlnln
)|(
)|(ln
q
px
q
px
q
px
qxf
pxfiii
i
i .
Kulback-Leibler divergence between the probability density
function f(xi | p) and f(xi | q) is given by
3
33
2
22
1
11 lnlnln)|(
q
px
q
px
q
pxEqpK iiip
3
33
2
22
2
11 lnlnln
q
pnp
q
pnp
q
ppn .
The intrinsic discrepancy between f(xi | p) and f(xi | q) is
)|(,)|(min),( pqKqpKqp .
Then the intrinsic statistic is given by
dpxppqqpExqd i
ppi )|(),(]),([),( 2 .
The intrinsic statistic cannot be found in closed form, but may
easily computed by numerical integration. Point estimation
q* will minimize intrinsic statitic, i.e.,
),(minarg)(** iq
i xqdxqq
where
= { ( q1, q2, q3) | 0 < q1, q2, q3 < 1 and q1 + q2 + q3 = 1 }.
To describe the method, suppose we have x = ( x1, x2, x3 ) =
(1,12,2) i. e. it is only 1 respondent gives score 1, 12
respondents give score 2 and 2 respondents give score 3.
Based on multinomial distribution model and by using
Determining Teaching Quality of Lecturer Based on
Questioner Using Multinomial Distribution & Objective
Bayesian
Adi Setiawan,
S
The Third Basic Science International Conference - 2013 M33-2
objective Bayesian method, we will get the estimation
parameter p = (p1, p2, p3) = (0,08, 0,88, 0,15) and the MLE of
parameter p = (p1, p2, p3) is (0,07, 0,80, 0,13). The estimate
will minimize intrinsic statistical value. In this case, the
intrinsic statistical value is presented in Figure 1. In other
hand, if we have x = ( x1, x2, x3 ) = (0,2,5) and by using
objective Bayesian method we will get (0,06, 0,29, 0,65) but,
the MLE is (0, 0,29, 0,71). Thus, we can see that p1 will not
be zero eventhough x1 = 0. Figure 2 presents the intrinsic
statistical value for p given data x = ( x1, x2, x3 ) =
(0,2,5).
0 1000 2000 3000 4000
0.0
00
.05
0.1
00
.15
0.2
00
.25
0.3
00
.35
Intrinsic Statistic value
Index
Intr
insi
c S
tatis
tic
Figure 1. The intrinsic statistical value for p given data
x = ( x1, x2, x3 ) = (1,12,2).
III. METHODS
Data consists of 120 sheets of questioner from 9 courses.
Every sheet of questioner contains answers of 16 items or
questions. Based on the answer of questioner for every
respondent, we can determine value of xi = ( xi1, xi2, xi3) i. e.
the number of score i where i = 1, 2, 3 for every courses and
then the parameter p = (p1, p2, p3) is estimated using objective
Bayesian method. We assume that answer of respondent for
every item will be independent each other. To measure the
teaching quality for every course we can use statistic
3/)32(%100 321 pppT
(in percent). The statistic T will be lay between 0 and 100
percent. The statistic T will give the measure of the quality of
lecturer for every course.
0 1000 2000 3000 4000
0.0
00
.05
0.1
00
.15
0.2
00
.25
0.3
0
Intrinsic Statistic value
Index
Intr
insic
Sta
tistic
Figure 2. The intrinsic statistical value for p given data
x = ( x1, x2, x3 ) = (0,2,5).
IV. RESULTS AND DISCUSSION
Based on 120 sheets of questioner form 9 courses, we
analyze the data using multinomial distribution model and
objective Bayesian method. Table 1 presents the result of the
teaching quality for every courses. The analysis of T
statistical value using T based on MLE and objective Bayesian
method are present in Table 2 and Table 3, respectively. We
can see that Course 4 becomes the higest teaching quality and
Corse 9 becomes the lowest teaching quality. Thus, the result
of analysis will be moreless same as the MLE and statistics T
because the number of items times the number of respondent
are large.
Tabel 1. Teaching Quality for every courses based on questioner sheet.
No. Course 16n x = ( x1, x2, x3 )
1 Course 1 352 (60, 175, 117)
2 Course 2 304 (40, 141, 123)
3 Course 3 208 (5, 96, 107)
4 Course 4 192 (2, 55, 135)
5 Course 5 208 (5, 96, 107)
6 Course 6 144 (6, 58, 80)
7 Course 7 176 (7, 94, 75)
8 Course 8 176 (23, 86, 67)
9 Course 9 224 (43, 148, 33)
The methods can be extended for the number of answer for
every item is bigger than three. The research can be continued
to a simulation study based on the model to see the property of
The Third Basic Science International Conference - 2013 M33-3
estimation for every value of parameter space.
Tabel 2. Teaching Quality for every courses based on MLE.
No. Course 16n p T
1 Course 1 352 (0,17, 0,5, 0,33) 72,06 %
2 Course 2 304 (0,13, 0,46, 0,41) 75,77 %
3 Course 3 208 (0,03, 0,46, 0,51) 83,01 %
4 Course 4 192 (0,02, 0,28, 0,70) 89,76 %
5 Course 5 209 (0,02, 0,46, 0,51) 83,01 %
6 Course 6 144 (0,04, 0,40, 0,56) 83,79 %
7 Course 7 176 (0.04, 0.53, 0.43) 79 ,55%
8 Course 8 176 (0,13, 0,49, 0,38) 75 %
9 Course 9 224 (0,19, 0,66, 0,15) 65,18%
Tabel 3. Teaching Quality for every courses based on objective Bayesian
method.
No. Course 16n p T
1 Course 1 352 (0,17, 0,5, 0,33) 72 %
2 Course 2 304 (0,14, 0,46, 0,40) 75,33 %
3 Course 3 208 (0,02, 0,46, 0,52) 83,33 %
4 Course 4 192 (0,02, 0,28, 0,70) 89,33 %
5 Course 5 209 (0,10, 0,56, 0,34) 74,67 %
6 Course 6 144 (0,04, 0,40, 0,56) 84 %
7 Course 7 176 (0.04, 0.54, 0.42) 79,33 %
8 Course 8 176 (0,14, 0,48, 0,38) 74,67 %
9 Course 9 224 (0,18, 0,66, 0,16) 66 %
REFERENCES
[1] Ahmed, I, M. M. Nawaz, Z. Ahmad, Zafar Ahmad, M. Z,
Shaukat, A. Usman, Wasim-ul-Rehman, N. Ahmed,
(2010), Does service quality affect student’s
performance? Evidence from institutes of higher learing,
African Journal of Bussiness M anagement Vol. 4 (12)
[2] Barone, S and E. L. Franco, 2010, TESF Methodology for
Statistics Education Improvement, Journal of Statistics
Education, Vol. 18 (3)
[3] H. A. Parhusip, H. A., & A. Setiawan (2011) Modelling
on Lecturer’s Performance with Hotteling-Harmonic-
Fuzzy, The 6th SEAMS GMU 2011 July 12-15.
[4] Setiawan, Adi & Hanna Arini Parhusip (2011)
Pengukuran Kualitas Pengajaran Dosen Berdasarkan
Kuesioner dengan Menggunakan Hotelling, Prosiding
SemNas Statistika Undip 2011.
[5] Setiawan, A., & Hanna A Parhusip (2011) Determine
Teaching Quality of Lecturer Based on Questioner Using
T Statistics, ICREM 5, Bandung, 22-24 October 2011.
[6] Setiawan, A. (2011) Penggunaan Metode Bayesian
Obyektif dalam Analisis Pengukuran Tingkat Kepuasan
Pelanggan berdasarkan Kuesioner, Prosiding Seminar
Nasional Matematika dan Pendidikan Matematika, UNY
Yogyakarta 3 Desember 2011.
The Third Basic Science International Conference - 2013
PSM14-1
Abstract— The coal mining sector that is the mainstay
products of interest to investors in Kalimantan Selatan,
contributes about 17.56% of the Gross Domestic Product
of South Kalimantan. This paper described the application
of the spatial statistical technique, Inverse Distance
Weighting (IDW) and Ordinary Kriging (OK), to estimate
the mineral reserve such coal deposit in Kabupaten Hulu
Sungai Utara. Ordinary kriging and Inverse Distance
Weighting are linear interpolators as the methods in
mining grade control and mine resource estimation.
Kriging, that is commonly described as minimum variance
estimator, would give the best estimation when the
neighbourhood is properly defined. Kriging can be a very
effective statistical method for limiting the number of
samples needed to spatially characterize objects while still
insuring adequate data quality. The result indicate that
IDW and OK performed equally well in estimating the
thickness of coal deposit.
Index Terms— Inverse Distance Weighting, Ordinary
Kriging, A Coal Deposit.
I. INTRODUCTION
nterpolation is an estimation of a variable at an unmeasured
location from observed values at surrounding locations. All
interpolation algorithms (inverse distance squared, splines,
radial basis functions, triangulation, etc.) estimate the value at a
given location as a weighted sum of data values at surrounding
locations. Almost all assign weights according to functions that
give a decreasing weight with increasing separation distance.
Kriging assigns weights according to a (moderately) data-
driven weighting function, rather than an arbitrary function, but
it is still just an interpolation algorithm and will give very
similar results to others in many cases [1]. The estimates will
be fairly good if the data locations are fairly dense and
uniformly distributed throughout the study area regardless of
interpolation algorithm. The estimates will be unreliable if the
data locations fall in a few clusters with large gaps in between
regardless of interpolation algorithm. Almost all interpolation
algorithms will underestimate the highs and overestimate the
Dewi Sri Susanti is lecturer of MIPA Faculty, Lambung Mangkurat
University Banjarmasin (corresponding author to provide phone:
08152149700; e-mail: dew_oqi@ yahoo.com).
lows; this is inherent to averaging and if an interpolation
algorithm didn’t average we wouldn’t consider it reasonable.
Kriging is a geostatistical method of spatial data interpolation
that can be used to estimate mine resource. In 1963 G.
Matheron named Kriging after D.G. Krige, a South African
mining engineer, who used the technique to more accurately
predict the extent of gold deposits in unsampled areas [1].
Kriging is an interpolation method that optimally predicts data
values by using data taken at known nearby locations. Kriging
can be either two-dimensional or three-dimensional.
Kriging is a set of linear regression routines which minimize
estimation variance from a predefined covariance model.
Kriging is based on the assumption that the parameter being
interpolated at a site is a regionalized variable. A regionalized
variable varies in a continuous manner spatially so that data
values from points nearer each other are more correlated. Data
values from widely separated points are statistically
independent in kriging. [2].
There are some advantages of kriging i.e: helps to compensate
for the effects of data clustering, assigning individual points
within a cluster less weight than isolated data points, gives
estimate of estimation error (kriging variance), along with
estimate of the variable, Z, itself. Availability of estimation
error provides basis for stochastic simulation of possible
realizations of Z(u).
II. LINEAR SPATIAL INTERPOLATION
A. Inverse Distance Weighting
Inverse Distance Weighting (IDW) is one of the linear
interpolators to estimate spatial data, as is Ordinary Kriging
(OK). A relatively non-mathematical understanding of linear
weighted averaging can be gained from thinking about linear
regression. In linear regression, the relationship between two
variables, x and y, is considered to be a straight line (i.e.
linear). The formula for this straight line is simple: y = ax + b.
Where a is the slope of the line and b is the value of y when x
equals zero (i.e. the y-intercept). If we specify a particular
value of x we can therefore conveniently determine the
expected y value corresponding to this x. It doesn’t matter
whether we specify an x value which is very small or very
large, or anywhere in-between: the relationship between x and
y is always the same as the specified straight line. In other
words, the formula used to estimate y does not alter as the
Spatial Interpolation Comparison in Estimating A Coal
Deposit in Kabupaten Hulu Sungai Utara, South
Kalimantan, Indonesia
Dewi Sri Susanti
I
The Third Basic Science International Conference - 2013
PSM14-2
magnitude of the x value changes [3].
A linear interpolator has this property: the weights we assign
to each of the N sample locations inside our estimation
neighbourhood are independent of the specific data values at
these locations. Think about the simplest kind of linear
interpolator, IDW. An IDW estimate assigns the weight to a
sample located within the estimation neighbourhood as:.
N
j j
ii
d
d
i
1
1
Where λ are the weights, d are the distances from each
sample location to the centroid of the block to be estimated
and α is the power. Once the power to be used is specified, the
ith
sample is assigned a weight that depends solely upon its
location (distance di to the centroid). Whether the sample at
this location had an average or extreme value does not have
any impact whatsoever on the assignment of di λ [4].
OK is a more sophisticated linear interpolator proposed by
Matheron (1962). OK’s advantage over IDW as a linear
estimator is that it ensures minimum estimation variance given:
a specified model spatial variability (i.e. variogram or other
characterisation of spatial covariance/correlation), and a
specified data/block configuration. The second criterion
involves knowing the block dimensions and geometry, the
location and support of the informing samples, and the search
(or “Kriging neighbourhood”) employed. Minimum estimation
variance simply means that the estimation error is minimised by
OK. Given an appropriate variogram model, OK will
outperform IDW because the estimate will be smoothed in a
manner conditioned by the spatial variability of the data
(known from the variogram).
B. Variogram
In ordinary kriging [5], a variogram is first constructed using
a spatial set of soil or sediment data, for example, from a site.
A variogram has two parts: an experimental data and a model
variogram. An experimental variogram is constructed by first
calculating the variance of each point in a dataset with respect
to each of the other points. The experimental variogram
consists of the plotted variances versus the distance between
each data point at the site. The typical variogram was
calculated using the following formulae:
hN
i
ii szhszhN
h1
2
2
1
The model variogram is a curved line through the experimental
variogram points. The model variogram represents a simple
mathematical function modeling the trend in the points of the
experimental variogram. The variogram in kriging can be used
to calculate the expected error of estimation at each target
interpolation point since the estimation error is a function of
the distance to surrounding data points. There are four types
of model functions that support for building model
variograms. Each of the functions are characterized by a
nugget, contribution and range. The four model supported are:
spherical, exponential, gaussian and power [6].
The expected estimation error is minimized in a least squares
sense in kriging by using the variogram to compute weights in
the kriging equations. For this reason, kriging is said to
produce the best linear unbiased estimate. In most mapping
software manuals, kriging is recommended as the best
interpolation method.
III. STATISTICAL ANALYSIS AND DATA
SUBDIVISION
The study was conducted on a coal deposit. The deposit
extends over an area of about 16 km2 in Hulu Sungai Utara,
South Kalimantan. The thickness anf the depth of coal deposit
was observed to estimate the value of unobserved area. Prior
to modeling, detailed statistical analyses of the composite data
were carried out, because these data are the basis for the ore
grade estimation. Table 1 presents the descriptive statistics of
the data sets containing all the values [6]. The table shows that
the distribution of data variable were not skewed, ( value of
kurtosis and skewness between -1 and 1) respectively.
Table 1. Basic statistics of the observed data set
Statistics X Y Thickness Depth
Mean 295922.12 9779851.44 1.13 14.68
N 112.00 112.00 112.00 112.0
0
Std. Deviation 61.92 68.72 0.39 8.02
Variance 3834.50 4723.08 0.15 64.38
Kurtosis -0.66 -0.91 -0.11 -0.81
Skewness 0.17 -0.32 1.00 0.30
Minimum 295756.00 9779715.00 0.68 1.55
Figure 1 presents the normal Q-Q plots of thickness and
depth of coaldata. From these plots it can be seen that
thickness and depth are normally distributed. However, K-S
tests conducted on the dataof these variables indicated that the
data follow a normal distribution and it was statistically
significant at 5% level of significance.
The Third Basic Science International Conference - 2013
PSM14-3
Figure 1. Normal Q-Q Plots of Thickness & Depth of coal
deposit.
Since the data meet the assumption of normally distributed
and stationary then IDW and OK was applied to estimate the
coal data [7]. The spherical and Gaussian variogram performed
the best fitting for data covariance (Figure 2). The spherical
variogram characterized with nugget of 0.07, a sill of 0.175,
and a range of 20 m. The gaussian variogram characterized
with nugget of 0.07, a sill of 0.175, and a range of 30 m.
Figure 2. The spherical and Gaussian variogram
To derive an effective measure of model performance, the
data available for this study were divided into two sets: training
and testing. The model was trained using training data, and its
performance was validated using testing data. It is worth
pointing out that these two data sets should have similar
statistical characteristics: there is no point training the model
with data that has no relevance to the testing data [8]. This
would also lead to biased model performance This study
followed the conventional practice of randomly dividing the
data into training and testing sets. Instead of simple random
data division, the data were randomly divided in two groups.
Both mean and standard deviation values are close for all the
attributes. Further, the statistical similarity of the two data sets
was checked using F test. The F test result confirmed that both
the data sets are statistically similar at 0.05 level of
significance.
Table 2 Statistics of training and testing data
Statistics Data set X Y Thickness Depth
Mean Training 295922.12 9779851.44 1.13 14.68
Testing 296112.44 9779899.01 1.25 13.86
Std.
Deviation
Training 61.92 68.72 0.39 8.02
Testing 60.09 71.20 0.44 7.75
The validity of the OK model was established through a
comparative evaluation between IDW and OK. To derive a
legitimate model comparison, the same data set which was
used to train the OK model was used to developing the kriging
model. Finally, the effectiveness of the two models was
examined using the testing data set. For comparison of the
result, three statistical indices, mean error, R2 and mean
squared error were used. Table 3 shows the statistical summary
of the comparative results of the OK and IDW techniques for
both attributes. It is apparent from Table 3 that both IDW and
OK methods have performed equally well.
Table 3 Error statistics of IDW and OK based estimation of
testing data
Statistics Method Thickness Depth
Mean
Squared Error
IDW 0.000104 15.6632
OK 0.000088 11.0628
R2 IDW 0.774 0.651
OK 0.882 0.843
Mean Error IDW -0.001572 5.025
OK 0.002451 6.027
The mean squared error as well as R2 (coefficient of
determination) values indicate that the OK model works
slightly better than the IDW model for both variables
(thickness and depth of coal deposit. Further, the R2 values of
the OK model for both attributes are reasonably high, which
indicates that a reliable grade model can be constructed for the
deposit. All the modeling approaches had low prediction bias.
Figures 3 presents the contour plot of mining area for observed
value and estimating value using OK model.
The Third Basic Science International Conference - 2013
PSM14-4
IV. SUMMARY
This paper used two techniques - Inverse Distance
Weighting (IDW) and Ordinary Kriging (OK) – to model the
thickness and depth of coal deposit in Hulu Sungai Utara,
South Kalimantan. The sample set was carefully divided into
two groups as modeling and testing sets to ensure that
performance evaluation was valid. Both approaches, IDW and
OK, performed equally (in term of mean error (bias) and mean
squared error) on both variables, thickness and depth of coal
deposit. Since the R2 values of OK model are higher than IDW
model, it apparent that prediction of OK model was slightly
better than IDW technique.
A. References
[1] Armstrong, M, Basic Linear Geostatistics, Springer,
Berlin, 1998.
[2] Krige, D. G, A basic persprective on the Roles of
Classical Statistics, Data Search Routines, Conditional
Biases and Information and Smoothing Effects in Ore
Block Evaluations. Proceedings Conferenceon Mining
Geostatistics. Kruger National Park. South Africa. pp: 1-
10, 1996.
[3] Cressie, N. Statistic for Spatial Data, Revised Edition.
New York: Willey. 1993.
[4] Matheron, G. Principles of Geostatistics. Economic
Geology. 58:1246-1266. 1963.
[5] Abdullah, Arik. Effects of Search Parameters on Kriged
Reserve Estimation. International Journal of Mining and
Geological Engineering. 8:319-331. 1990.
[6] David, M. Geostatistical Ore Reserve Estimation
(Developments in Geomathematics 2). Elsevier.
Amsterdam. 1977.
[7] Vann, J. and Guibal, D. Beyond Ordinary Kriging – An
Overview of Non-Linear Estimation. In Mineral
Resource and Ore Reserve Estimation. The AusIMM
Guide to Good Practice. Monograph 23. pp: 249-256.
2000.
[8] Samanta, B, Ganguli, R. and Bandopadhyay. Comparing
The Predictive of Neural Networks with Ordinary Kriging
in Bauxite Deposit. Mining Technology (Trans. Inst. Min.
Metall. A). Vol. 114:A129-A139. September 2005.
The Third Basic Science International Conference - 2013 AU-1
NAME Institute COUNTRY E-Mail
Dann Mallet Queensland University of
Technology Australia [email protected]
Hideo Tsuboi Nagoya University Japan [email protected]
Kwang-Ryeol
Lee
Korea Institute of Science and
Technology South of Korea [email protected]
Lidia Morawska Queensland University of
Technology Australia [email protected]
M. Nurhuda Brawijaya University Indonesia [email protected]
Nurul T.
Rochman
Indonesian Institute of
Sciences Indonesia [email protected]
Petr Solich Charles University Czech
Republic [email protected]
S.K. Lai National Central University Taiwan [email protected]
Agus Z. Arifin Sepuluh Nopember Institute
of Technology Indonesia [email protected]
Adi Setiawan Satya Wacana Christian
University Indonesia [email protected]
Amran Sepuluh Nopember Institute
of Technology Indonesia amranihsani@ gmail.com
Ani Budi Astuti Brawijaya University Indonesia [email protected]
Anik Djuraidah Bogor Agricultural University Indonesia [email protected]
Ari Suparwanto Gadjah Mada University Indonesia
Arif Rahman
Hakim University of Indonesia Indonesia
Arman Gadjah Mada University Indonesia [email protected]
Asep Saefuddin Bogor Agricultural University Indonesia [email protected]
Brodjol S. S.
Ulama
Sepuluh Nopember Institute
of Technology Indonesia [email protected]
Ch. Rini Indrati Gadjah Mada University Indonesia
Dewi Sri
Susanti
Lambung Mangkurat
University Indonesia dew_oqi@ yahoo.com
Endang
Widiyastuti University of Indonesia Indonesia
Eprina Eksa
Gutami Yogyakarta State University Indonesia [email protected]
Erma Suwastika Bandung Institute of
Technology Indonesia [email protected]
Erni Tri Astuti Sepuluh Nopember Institute
of Technology Indonesia [email protected]
Hardinsyah Bogor Agricultural University Indonesia [email protected]
Heri Kuswanto Sepuluh Nopember Institute
of Technology Indonesia [email protected]
Herlina Hanum Sriwijaya University Indonesia linhanum@ yahoo.com.au
The Third Basic Science International Conference - 2013 AU-2
Hossein
Mohammadikia
Universiti Teknologi
Malaysia Malaysia
I Nyoman
Budiantara
Sepuluh Nopember Institute
of Technology Indonesia [email protected]
Ida Mariati
Hutabarat Cenderawasih University Indonesia [email protected]
Intan Muchtadi-
Alamsyah
Bandung Institute of
Technology Indonesia
Irhamah Sepuluh Nopember Institute
of Technology Indonesia [email protected]
Ismaini Zain Sepuluh Nopember Institute
of Technology Indonesia [email protected]
J. K. Wororomi Sepuluh Nopember Institute
of Technology Indonesia [email protected]
Kartika
Fithriasari
Sepuluh Nopember Institute
of Technology Indonesia [email protected]
Lisa Nesti Akademi Teknologi Industri
Padang Indonesia [email protected]
M. Mashuri Sepuluh Nopember Institute
of Technology Indonesia [email protected]
Md Nor bin
Bakar
Universiti Teknologi
Malaysia Malaysia
Moch. Aruman
Imron Brawijaya University Indonesia [email protected]
Mohamad
Dokhi Sekolah Tinggi Ilmu Statistik Indonesia [email protected]
Muhammad
Rifki Taufik Yogyakarta State University Indonesia [email protected]
Muhammad
Syifa’ul Mufid
Sepuluh Nopember Institute
of Technology Indonesia [email protected]
Mukhsar Sepuluh Nopember Institute
of Technology Indonesia [email protected]
Nelly Oktavia
Adiwijaya Jember University Indonesia [email protected]
Nur Iriawan Sepuluh Nopember Institute
of Technology Indonesia [email protected]
Preatin Sepuluh Nopember Institute
of Technology Indonesia [email protected]
Purhadi Sepuluh Nopember Institute
of Technology Indonesia [email protected]
Rahmawati
Pane
Sepuluh Nopember Institute
of Technology Indonesia
d
Rara Sugiarti Sebelas Maret University Indonesia
Rita Diana Sepuluh Nopember Institute
of Technology Indonesia [email protected]
Salmah Gadjah Mada University Indonesia
Satwiko
Darmesto
National Institute of Public
Administration Indonesia [email protected]
The Third Basic Science International Conference - 2013 AU-3
Scott McCue Queensland University of
Technology Australia
Sony Sunaryo Sepuluh Nopember Institute
of Technology Indonesia sonny_s@ statistika.its.ac.id
Sri Subanti Sebelas Maret University Indonesia [email protected]
Subiono Sepuluh Nopember Institute
of Technology Indonesia
Sutikno Sepuluh Nopember Institute
of Technology Indonesia [email protected]
Tony Karnain Universiti Teknologi
Malaysia Malaysia [email protected]
Trisilowati Brawijaya University Indonesia [email protected]
Wendy Hartanto
Deputy for Population
Management National Family
Planning Coordination Board
(BKKBN)
Indonesia [email protected]
Widodo Gadjah Mada University Indonesia
The Third Basic Science International Conference - 2013 ACK01
Acknowledgement The Program Committee would like to thank the followings for their supports:
Universitas Brawijaya
PT. Semen Gresik
PT. PLN (Persero)
The Third Basic Science International Conference - 2013 ACK02
The Third Basic Science International Conference - 2013 ACK03