chapter 1. what is statistics? ir.muhril ardiansyah,m.sc.,ph.d.1 statistic descriptive

Chapter 1. What Is Statistics?

Ir.Muhril Ardiansyah,M.Sc.,Ph.D. 1

Statistic Descriptive

http://statisticdescriptive.wordpress.com/



Lecturer

Ir. Muhril Ardiansyah, M.Sc., Ph.D Email: [email protected]



Text

Lind, Marchal, Wathen. 2008. Statistical Techniques in Business and Economics with Global Data Sets. Mc Graw Hill International Edition.

Note: Student must bring the textbook to the class, since we discuss case and examples from the textbook.



Blog

http://statisticdescriptive.wordpress/



Grading

The grading will be used based on the following components:

Participation : 10 % Homework / Quiz : 20 % Mid term exam : 30 % Final exam : 40 % TOTAL : 100 %



Rules In Class

Turn Off HP. Late more than 15 minutes cannot

attend the class. 07:45 am is the latest time to enter

the class.



Materials Ch 1. What is

statistics? Ch 2. Describing

data: frequency tables, frequency distributions, and graphic presentation.

Ch 3. Describing data: numerical measures.

Ch 4. Describing data: displaying and exploring data.

Ch 5. A survey of probability concepts.

Ch 6. Discrete probability distributions.



Materials (continued) Ch 7. Continuous

probability distributions.

Ch 8. Sampling methods and the central limit theorem.

Ch 9. Estimation and confidence intervals.

Ch 10. One sample tests of hypothesis.

Ch 13. Linear regression and correlation.

Ch 16. Time series and forecasting.



Chapter 1.What Is Statistics?



Why Study Statistics? Numerical information is everywhere.

Statistical techniques are used to make decisions that affect our daily lives.

Knowledge of statistical methods will help you understand how decisions are made and give you a better understanding of how they affect you.



What Is Meant By Statistics?

Statistics: The science of collecting, organizing,

presenting, analyzing, and interpreting data to assist in making more effective decisions.



What Is Meant By Statistics?

Chart 1-1 Page 5.



Frito Lay Volume and Share of Major Snack Chip Categories in US Supermarkets

Potato Chips 64% Rest

Tortilla Chips 75% Rest

Pretzels 26%



Types Of Statistics

1. Descriptive statistics.2. Inferential statistics.



Types Of Statistics (continued)Descriptive statistics:Methods of organizing, summarizing, and presenting data in an informative way.

Example:- The population of the United States was 179 323 000 in 1960 203 302 000 in 1970 226 542 000 in 1980



Types Of Statistics (continued)

Inferential statistics (statistical inference):The methods used to estimate a property of a population on the basis of a sample.

Population:The entire set of individuals or objects of interest or the measurements obtained from all individuals or objects of interest.




Sample:A portion, or part, of the population of interest.

Reasons for sampling?




Population: all items.

Sample: items selected from the population.



Types Of Variables

1. Quantitative.2. Qualitative.

Qualitative variable (attribute):Characteristic being studied is non numeric.Such as: gender, Religious, State of birth,



Types Of Variables (continued)

Quantitative variable:Characteristic being studied is numeric.

Quantitative variables: 1. Discrete. 2. Continuous.




Discrete variables:Assume only certain values, and there are “gaps” between the values.Example: number of bedrooms in a house.

Continuous variables:Assume any value within a specific range.Example: weight.




Chart 1-2 Page 9

Types Of Variables

Qualitative Quantitative

Discrete Continuous



Levels Of Measurement

1. Nominal level data.2. Ordinal level data.3. Interval level data.4. Ratio level data.



Levels Of Measurement (continued)

Nominal level data: Data categories are represented by

labels or names. Even when the labels are numerically

code, the data categories have no logical order.

Table 1-1 Page 10



Table 1-1 Source Of World Oil Supply For 2004

Source Millions Of Barrels Per Day

Percent

OPEC 32.91 39.7

OEDC 22.76 27.4

Former USSR 11.33 13.7

China 3.62 4.4

Other 12.35 14.9




Ordinal level data: Data classifications are represented by

sets of labels or names (high, medium, low) that have relative values.

Because of the relative values, the data classified can be ranked or ordered.

Table 1-2 Page 11



Table 1-2 Rating Of A Finance Professor

Rating Frequency

Superior 6

Good 28

Average 25

Poor 12

Inferior 3




Interval level data: Ordinal level. The difference between values is a

constant size. Data classification are ordered. Equal differences in the characteristics are

presented by equal differences in the measurements.

Table Page 12



Table Page 12

Size Bust (In) Waist (In) Hips (In)

8 32 24 35

10 34 26 37

12 36 28 39

14 38 30 41

16 40 32 43




Ratio level data: Has all the characteristics of the interval level. The 0 point is meaningful. The ratio between two numbers is meaningful. Such as: money, weight,

Table 1-3 Page 13



Table 1-3 Father-Son Income Combination

Name Father Son

Lahey $ 80 000 40 000

Nale 90 000 30 000

Rho 60 000 120 000

Steele 75 000 130 000



Ethics And Statistics

Practice statistics with integrity and honesty.

Urges us to do the right thing when collecting, organizing, summarizing, analyzing, and interpreting numerical information.



Homework

No. 9 Page 16.

http://statisticdescriptive.wordpress.com/



QuizFor the following questions, would you collect information using a sample or a population? Why?

1.a. Statistics 201 is a course taught at university. Prof. Verage has taught nearly 1500 students in the course over the past 5 years. You would like to know the average grade for the course.

1.b. As part of a research project, you need to report the average profitability of the number one corporation in the Fortune 500 for the past 10 years.

1.c. You are looking forward to graduation and your first job as a salesperson for one of five large pharmaceutical corporations. Planning for your interviews, you will need to know about each company’s mission, profitability, products, and markets.

chapter 1. what is statistics? ir.muhril ardiansyah,m.sc.,ph.d.1 statistic descriptive

Documents

muhril ardiansyah

descriptive statistics

types of statistics

study statistics

inferential statistics

wordpress slide

materials ch

interpreting data