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PLEASE DO NOT QUOTE OR CIRCULATE THE PAPER WITHOUT THE EXPLICIT PERMISSION
OF THE AUTHORS
Sources of Total Factor Productivity Growth in the Manufacturing
Sector across Selected OECD Countries
Lili Hao1
Industry Canada
Prepared for the CEA 2009 Conference
Abstract:
In this paper I study the sources of total factor productivity (TFP) growth in 13 selected OECD
countries’ manufacturing industries including Canada over the period 1980-2004. A stochastic
frontier production framework has been applied to decompose TFP growth into three
components: namely technological progress, changes in technical efficiency and economies of
scale. I find that technological progress contributes the most to total manufacturing TFP growth
in all countries and it explains cross-country differences in the ranking of total TFP growth. The
changes in technical efficiency and economies of scale only contribute minuscule to TFP growth.
The constant returns to scale assumption could hold in these countries’ manufacturing industries.
The decompositions of TFP growth in three sub-groups (low-tech, high-tech and resource-based)
manufacturing industries also have been studied.
Keywords: Total Factor Productivity, Technological Progress, Technical Efficiency
JEL classification: O3-Technological Change, Productivity
1 This working paper reports preliminary results of research and analysis undertaken by the Economic
Research and Policy Analysis (ERPA) Branch of Industry Canada. All opinions expressed in this paper are
entirely my own and should not in any way reflect those of Industry Canada or the Government of Canada.
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I: Introduction
The manufacturing sector has historically been the main driver of aggregate output
growth in OECD countries. Although the employment and output share of the
manufacturing sector in the total economy has declined in recent years, mainly due to
strong productivity growth and a gradual process of structural change to a more service-
oriented economy, this sector still shows strong performance in the OECD total economy
and innovation. For instance, the manufacturing industries make significant contributions
to the Canadian economy. The sector accounts for about 16% of Canada’s gross domestic
product in 2007 and is vital to many communities and provinces economies. It notes that
although manufacturing production is declining in OECD countries, innovation in this
sector continues to be dominated by OECD countries. However, Canadian manufacturing
industries lagged behind many OECD countries in productivity growth, especially their
U.S. counterparts. Moreover our economic environment has been changing very quickly.
Canadian manufacturing industries are facing serious competitive challenges from lower-
cost global competition, relatively higher energy prices, and weaker global demand,
particularly from the U.S, and the manufacturing sector is in a period of decline. The role
of productivity growth has become increasingly important to future Canadian
manufacturing industries’ growth and a better understanding of the sources of total factor
productivity growth will help these industries achieve international competitiveness and
long-term growth.
Neoclassical growth models argue that economic growth is not sustainable without
continuous total factor productivity growth since input factor accumulation exhibits
diminishing returns that are eventually self-defeating. Solow (1957) attributed output
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growth to input growth and technical change. However, TFP growth differences could
result from either technological progress, efficiency gains or change in economies of
scale. It is particularly relevant to distinguish between technological progress and
changes in technical efficiency in studying productivity performance. Technological
progress is defined as the change in the best practice production frontier and its rate can
be estimated directly from a deterministic frontier production function. Technical
efficiency change refers to all other productivity changes; for example, learning by doing,
diffusion of new technological knowledge, improved managerial practices as well as the
short run adjustments to shocks external to the enterprises. Given a level of technology,
resource allocation may be required to reach the “best-practice” level of technical
efficiency over time. Such productivity gains from technical efficiency improvement are
substantial and may outweigh gains from technological progress. It is therefore important
to know how far one economy is away from the technological frontier at some point and
how quickly it can reach the frontier.
The issue then becomes how to decompose TFP growth into its components and find
the sources of productivity change. It is always of interest for economists to measure and
identify the sources of productivity change. Fisher (1922) and Tornqvist (1936) provided
early examples of constructing superlative productivity indices using price and quantity
data. Researchers also measured productivity change by computing a Malmquist (1953)
productivity index. Fare, Grosskopf, Norris, and Zhang (1994) developed a
nonparametric technique to construct Malmquist productivity indexes, to analyze the
productivity growth decomposition for a sample of OECD countries. Sharma, Sylwester
and Margono (2007) criticized that their approach is deterministic and therefore it labels
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any deviation from the frontier as inefficient. “It did not allow for the possibility of
random events or for other factors to affect output. One can also compute a Malmquist
productivity index with a stochastic frontier model but only if one assumes constant
returns to scale. It is a very restrictive assumption”.
Nishimizu and Page (1982) conducted a productivity change analysis on Yugoslavia
and estimated the sources of TFP growth. They proposed a methodology that
decomposed total factor productivity change into technological progress and changes in
technical efficiency. The econometric model used in the above study is called the frontier
model, first proposed by Farrell (1957) for the concept of output-oriented technical
efficiency and popularised by Aigner, Lovell and Schmidt (1977), and Meeusen and van
den Broeck (1977). This production frontier technique differs with the traditional growth-
accounting method developed by Solow (1957) in that the former now allows for
production below the best practice output, which is commonly observed empirically. The
frontier technique enriches Solow’s model by attributing growth in observed output to
movement along on the production frontier (input growth), movement toward the
production frontier (technical efficiency change), and shifts of the production frontier
(technological progress). They also explicitly included an inefficiency component in the
error term of the estimated production function to handle the lack of random shocks
problem in the Farrell (1957) paper.
Although the stochastic frontier production function allows for the existence of
technical inefficiencies in the production function, most of the previous theoretical
models had not explicitly formulated a model for these technical inefficiency effects in
terms of appropriate explanatory variables. Kumbhakar, Ghosh and McGuckin (1991),
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Reifschneider and Stevenson (1991) and Huang and Liu (1994) proposed models in
which the parameters of the stochastic frontier and the inefficiency model were estimated
given appropriate distributional assumptions. Battese and Coelli (1992, 1995) examined
the efficiency of paddy farmers in India and proposed a model with stochastic
inefficiency effects and a stochastic frontier production function for panel data. The
model permitted the estimation of both technological change in the stochastic frontier and
time-varying technical inefficiencies simultaneously.
Recent studies have applied the stochastic frontier estimation to compare efficiency
differences across countries or across regions within a country. Aaberg (1973), Shefer
(1973) and Sveikauskas (1975) were among the first to make regional productivity
estimates for the manufacturing sector. Wu (2000) used a parametric econometric model
and examined productivity growth in China’s reforming economy for 27 Chinese regions
panel dataset and filled the literature shortage in the assessment of economic growth in
East Asia countries without consideration of China’s performance. Adkins, Moomaw and
Savvides (2002) estimated technical efficiency across a wide sample of countries and
examined its relationship with measures of institutions and political freedom.
There are also several attempts to apply stochastic frontier estimation to U.S. states.
Significant interregional differences in productivity growth have been observed by
several researchers. Hutlen and Schwab (1984) concluded that the interregional
differences for the West North Central States in the growth rate of value added in the
manufacturing sector were primarily due to differences in input growth and not to
differences in productivity growth. Beeson and Husted (1989) examined manufacturing
industries across U.S. states and compared their productivity efficiency. A large portion
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of the variation was found to be related to regional differences in labor-force
characteristics, levels of urbanization and industrial structure. Most recently, Sharma,
Sylwester and Margono (2007) applied the parametric stochastic frontier production
model to the lower 48 U.S. states over the period 1977-2000 and decomposed the sources
of total factor productivity growth into technological progress, changes in technical
efficiency, and changes in economies of scale. Their model allowed for a stochastic
environment to explain the sources of TFP growth. They found that technological
progress comprised the majority of TFP growth but technical efficiency differences could
explain the cross-state differences in TFP growth.
In this paper, I apply the stochastic frontier methodology to selected 13 OECD
manufacturing sector (Australia, Austria, Canada, Denmark, Finland, France, Germany,
Italy, Japan, Netherlands, Portugal, Sweden, United Kingdom and the U.S) during the
period of 1980-2004 and explain their differences in the sources of TFP growth for total
manufacturing and three sub-groups (low-tech, high-tech and resource-based)
manufacturing industries across countries. Within manufacturing industries, large
differences in productivity growth have been observed for most OECD countries. For
example, in recent years, high-technology industries have typically experienced relatively
high rates of productivity growth while low-technology manufacturing industries have
tended to generate lower rates of productivity growth. By looking at the contributions
from technological progress, efficiency improvements and economies of scale, this study
can also help explain why some manufacturing industries grow faster than others,
especially if they have similar economic environments within countries.
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The paper is organized as follows. Section II presents the theoretical framework used
to decompose the growth of total factor productivity. Section III describes the dataset
used for 13 OECD countries manufacturing industries and Section IV presents the
estimated components of TFP growth for total and three-sub groups manufacturing
industries across OECD countries from 1980 to 2004. This stochastic frontier model also
allows us to see where Canadian manufacturing industries stand in the productivity
growth ranking and how to improve future productivity growth. A conclusion follows at
the end.
II: Stochastic Frontier Estimation Methodology:
(1) Technical efficiency
In neoclassical models, total output growth is usually attributed to input growth and
TFP growth. The contribution of TFP is always estimated as a residual after accounting
for the growth of inputs and is interpreted as technical progress. Such interpretation
implies that the improvement in productivity arises solely from technical progress, which
is valid only if firms operate on their production frontier, producing the maximum
possible output and realizing the full potential of current technology. However, in reality,
production is not always operating at the frontier and technically efficient. Much
empirical evidence suggests that production is carried out somewhere below the frontier
due to various factors, such as organizational inefficiencies. As a result, technical
progress cannot be the only source of total factor productivity growth. The stochastic
production frontier technique proposed by Farrell (1957) enriches Solow’s model by
attributing output growth to the sum of the three parts: movement along a path on the
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production frontier (input growth, changes in economies of scale), movement toward the
production frontier (technical efficiency gains), and shifts out of the production frontier
(technological progress). The decomposition of TFP growth into technological progress
and changes in technical efficiency and economies of scale can provide more information
on the status of the production technology being applied. This decomposition analysis
can also examine whether the given technology has been used in such a way that its full
potential has been realized and whether the technological progress is stagnant or
sustainable over time.
[Appendix A. Figure 1: Decomposition of output growth]
The decomposition of total output growth is graphically illustrated in Figure 1,
following the work by Kalirajan, Obwona, and Zhao (1996) and Wu (2000). In period 1
and 2, the given firm faces production frontiers F1 and F2 respectively. If production is
technically efficient, output would be y1* in period 1 and y2** in period 2. On the other
hand, if production is technically inefficient and does not operate on its frontier, then
realized output is only y1 in period 1 and y2 in period 2. Technical inefficiency (TI) is
measured by the vertical distance between the frontier output and the realized output of
the given firm, that is, TI1 in period 1 and TI2 in period 2, respectively. Hence the
change in technical efficiency overtime is the difference between TI1 and TI2.
Technological progress (TP) is measured by the distance between frontier F2 and frontier
F1, that is, (y2**−y2*) using x 2 input levels or (y1**−y1*) using x 1 input levels. The
contribution of input growth to output growth between period 1 and period 2 is denoted
as ∆ y x , which is the distance between y2** and y1**. The total output growth therefore
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can be decomposed into three components: input growth, technological progress and
technical efficiency change.
The decomposition could be expressed as follows:
D = y2−y1
= A + B + C
= [y1*−y1] + [y1**−y1*] + [y2-y1**]
= [y1*−y1] + [y1**−y1*] + [y2-y1**] + [y2**−y2**]
= [y1*−y1] + [y1**−y1*] − [y2**−y2] + [y2**−y1**]
= {[y1*−y1] − [y2**−y2]} + [y1**−y1*] + [y2**−y1**]
= (TI1−TI2) + TP + ∆ y x where: y2−y1= output growth
(TI1−TI2)= technical efficiency change
TP= technological progress
∆ y x = output growth due to input growth
Here I only briefly describe the stochastic production frontier for cross-sectional time
series data and the details will be provided in Appendix B.
Let y it denote the output of industry i=1, 2…, m, at time t=1, 2…, T.
y it = f (x it , t, β ) exp ( itε ) (1)
Suppose the stochastic frontier production function for panel data has two components:
the deterministic component and the stochastic component. The error term itε = itυ − u it
has two components. The deterministic component u it is associated with the technical
inefficiency of production. Following Battese and Coelli (1995), u it is obtained by
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truncation (at zero) of the normal distribution with mean itz⋅δ and variance 2
uσ2. The
non-negative condition reflects the fact that the industry may produce below its
production frontier and the inefficiency exists. itυ is assumed to be iid N~ (0, 2
vσ )
random two-sided errors, independently distributed, and represents the measurement
error statistical noise in the equation.
The production function can also be expressed by a logarithmic form:
ln y it =ln f(x it , t,β ) −u it + itυ (2)
The vector x it includes factor inputs for industry i at time t with β as a vector of
coefficients to be estimated. And itυ is the stochastic error term here.
The technical inefficiency components, u it , in (2) are specified as:
u it = δ z it + itω (3)
The z it is a (m × 1) vector of explanatory variables associated with technical
inefficiency of production over time, which could be country or industry specific factors
contributing to the inefficiency; and δ is an (1×m) vector of unknown coefficients. Here
itω are truncated normal random variables with zero mean and variance 2
uσ . This
truncation occurs at the point −δ z it , i.e. itω ≥ −δ z it . These assumptions are consistent
with u it being a non-negative truncation of the normal distribution N ~ (z it δ , 2σ ).
2 An alternative specification of the stochastic frontier model used by Stevenson (1980) is a normal-gamma
distribution. But truncated normal distribution form is more popularly used in the literature, such as Battese
and Coelli (1988, 1992, and 1995), Huang and Liu (1994), Y. Wu (2000), Jaume Puig-Junoy (2001),
Sharma, Sylwester, and Margono (2007), etc.
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The method of maximum likelihood3
is used to estimate the parameters of the
stochastic frontier and the technical inefficiency effects simultaneously, which is
originally derived by Battese and Coelli (1992, 1995).
The technical efficiency of production then is defined as follows,
TE it =E [exp (−u it )| itε ] = E [exp (−δ z it −ω it )| itε ] (4)
where itε = itυ − u it , u it ≥ 0
The prediction of the technical efficiencies is based on its conditional expectation,
given the model assumptions. In order to estimate the frontier and technical efficiency of
production, I also need to specify the functional form of f (x it , t, β ). I adopt the common
form of a translog production function. The translog production function was originally
developed by Christensen, Jorgenson and Lau (1971, 1973) and was used also by Battese
and Coelli (1992 and 1995)4.
Consider capital KIT (ICT capital) and KNIT (non-ICT capital), labor L and
intermediate inputs M are used for production. Technological change is captured by the
time trend, t, and the production function is allowed to vary over time.
Thus the translog function of f (x it , t,β ) is specified as:
ℓn f (x it , t,β ) = 0β + 1β ℓn KIT it + 2β ℓn KNIT it + 3β ℓn L it + 4β ℓn M it + 5β t +
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[ 6β (ℓn KIT it ) 2 + 7β (ℓn KNIT it )
2 + 8β (ℓn L it ) 2 + 9β (ℓnM it )
2 + 10β t 2 ] +
3 Ordinary least squares method for estimation is only valid when all economic agents operate production
at their efficient frontier. As a result, this traditional estimation will not reflect the frontier relationship with
the existence of inefficiency specified in this model. The likelihood function of (1) is derived in Appendix
B. 4 There are several advantages of using this type of function, for instance, the translog form allows for non-
constant returns to scale as well as for technical change to be both neutral and factor augmenting; partial
elasticities of substitution among inputs are allowed to vary and elasticity of scale can vary with output and
input proportions; also this translog form has more generality usages since CES and Cobb-Douglas
production functions are its special cases.
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11β ℓn KIT it * ℓn L it + 12β ℓn KNIT it * ℓn L it + 13β ℓn KIT it * ℓn M it +
14β ℓn KNIT it * ℓn M it + 15β ℓn L it * ℓn M it + 16β t *ℓn KIT it +
17β t *ℓn KNIT it + 18β t *ℓn L it + 19β t*ℓn M it (5)
Then substituting (5) into (2) gives the translog production frontier which will be
estimated by the maximum likelihood method using the computer program, FRONTIER
4.15.
(2) Total factor productivity (TFP)
The total change in frontier output can be measured by taking total differentiation of
(2) with respect to time:
•
y = dt
txfd ),,(ln β− dtdu
= t
txf
∂∂ ),,(ln β
+∑ ∂∂
j
x
txf
j
),,(ln β
dt
dx j− dtdu
(6)
Technological progress (TP) is measured by the first term on the right hand side of (6)
and in translog production function it gives:
t
txf
∂∂ ),,(ln β
=TP= 5β + 10β t + 16β ℓn KIT it + 17β ℓn KNIT it + 18β ℓn L it + 19β ℓnM it (7)
Rewriting the second term on the right hand side of (6):
∑ ∂∂
j
x
txf
j
),,(ln β
dt
dx j=∑
•
j
jj xe (8)
In the equation above, e j is the output elasticity of j-th input and •
x j is the change of
the j-th input over time. From the translog production function of (5),
5 For more information about the program, refer to Coelli (1992) for details.
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eitKIT = )ln(
)ln(
it
it
KIT
Y
∂∂
= 1β + 6β ℓnKIT it + 11β ℓnL it + 13β ℓnM it + 16β t (9)
eitKNIT = )ln(
)ln(
it
it
KNIT
Y
∂∂
= 2β + 7β ℓn KNIT it + 12β ℓnL it + 14β ℓnM it + 17β t (10)
eitL
= )ln(
)ln(
it
it
L
Y
∂∂
= 3β + 8β ℓnL it + 11β ℓn KIT it ++ 12β ℓn KNIT it + 15β ℓnM it + 18β t (11)
e M = )ln(
)ln(
it
it
M
Y
∂∂
= 4β + 9β ℓnM it + 13β ℓnKIT it + 14β ℓn KNIT it + 15β ℓn L it + 19β t (12)
The sum of eitKIT , e KNIT , e
itLand e
itM provides a measure of returns to scale.
The change in technical efficiency is expressed by ∆TE = − dtdu
Thus the total output change equation (6) can be denoted by:
•
y = TP + ∆TE + ∑•
j
jj xe (13)
From the equation above, the overall output change (•
y ) is not only affected by
technological progress and changes in inputs, but also by changes in technical efficiency.
As seen in Figure 1, the TP is positive (negative) if exogenous technical change shifts
the production frontier upward (downward) for a given level of inputs. If dtdu
is negative
(positive), then TE improves (deteriorates) over time.
Denoting •
TFP as output growth unexplained by input growth, the effect of TP and TE
change on TFP change will be:
•
TFP = •
y − ∑•
j
jj xs where s j is input j’s share in production cost. (14)
Substituting (14) into (13), gives:
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•
TFP = TP + ∆TE + (e-1) j
j
j x•
∑λ +•
−∑ jj
j
j xs )(λ (15)
where e=∑ je denoting a measurement of returns to scale6, ee jj /=λ
When price information is unavailable to determine costs, the allocative efficiency
component, the last term in (15) can not be calculated empirically. Following Sharma et
al. (2007) assumption, assuming ees jj /= for all j, thus reduces (15) to:
•
TFP = TP + ∆TE + ∑•
−j
je
exe j)1( (16)
The sources of total factor productivity growth are decomposed using the above
formula into three components: technological progress, changes in technical efficiency,
and changes in economies of scale.
III: Dataset Description
Using the methodology described in the previous section, I am able to decompose the
TFP growth of total manufacturing industries as well as three sub-group industries using
13 selected OECD industry-level data from 1980 to 2004. The three sub-groups of
manufacturing industries are defined as: Low-tech industries including Food, Beverage
and Tobacco industries and Textile, Textile Products, Leather and Footwear industries;
High-tech industries including Chemical, Rubber, Plastic, Fuel industries, Machinery,
Electrical and Optical Equipments industries, Transport Equipment industries and
Manufacturing NEC; and Resource-based industries including Wood and Wood products
6 Increasing K and L by a% will increase the output by more (less) than a% if there are increasing
(decreasing) returns to scale. If there are constant returns to scale, e=1, and changes in the quantity of
inputs do not affect changes in TFP.
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industries, Pulp, Paper, Printing and Publishing industries, Other Non-metallic Mineral
industries and Basic Metals, Fabricated metals industries.
The productivity growth is derived based on industrial gross output, so in the
production function the dependent variable is industrial gross output at constant 1995
prices. The independent variables in the production function are labor input measured by
total hours worked by employees; intermediate inputs measured at 1995 prices; ICT
Capital and non-ICT Capital inputs measured by ICT and non-ICT capital services at
1995 prices. All these data are from the EU KLEMS (March 2008) output data file. Gross
output purchasing power parity (PPP) at 1995 prices is used to adjust for the price
differences across countries.
The inefficiency vector z includes an intercept term and some industry-related
variables such as: an R&D intensity term, which is the share of total business expenditure
on R&D (BERD) in value-added; a trade openness term, which is the sum of total exports
and imports share of value-added; a human capital term proxied by the share of hours
worked by high-skilled persons (college or above) engaged; a business cycle factor
proxied by the percentage deviation from the value added trend; and a regulation impact
indicator defined as the growth rate of the regulation impact index. This data is from
OECD statistics regulation impact (RI) indicator datasets, which measures the sectoral
“knock-on” effects of regulation in non-manufacturing sectors7 on all sectors in the
economy. These sectors are the areas in which most economic regulations are
concentrated and where domestic regulations are most relevant to economic activity and
the welfare of consumers. Heavier regulation indicates more negative impacts on
efficiency improvement. In addition, I include some country dummy variables in the
7 Non-manufacturing sectors here include service sectors and energy sectors by OECD definitions.
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inefficiency function: Euro-European countries (countries which use the Euro as their
currency in the European Union), Non-Euro European countries (countries which do not
use Euro as their currency in the European Union), Oceania countries region (Australia
and Japan) and Canada. The control group is the United States.
The data for value-added, share of hours worked by high skilled persons engaged are
from the EU KLEMS (March 2008) output data file and the data for R&D are from the
OECD STAN BERD tables for each selected country.
IV: Empirical Application
The estimation results of the production frontier function and inefficiency components
are presented in Table 1. The individual coefficients of each variable in the production
function are not readily interpretable given the special form of the translog production
function (Beeson and Husted (1989)). More appropriate interpretation about inputs
elasticities and TFP growth decomposition are presented for this purpose in Table 2 and
Table 6.
[Table 1: Estimates of translog production function and inefficiency components]
A likelihood ratio test is conducted to check whether the Cobb-Douglas production
function is preferred over the translog function. The null hypothesis that the coefficients
6β ─ 19β are equal to zero is rejected at the conventional significance interval with a Chi-
squared statistic of 144.9 is significantly larger than the critical value of 22.36 with 13
degrees of freedom at the 5% significance level.
Also seen from Table 1, γ =68.7% denotes the variance of the inefficiency component
of the error term,2
uσ divided by the total variance22
vu σσ + . It suggests that the majority
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of the variation in the error term comes from the inefficiency component and is not
measurement error. The likelihood ratio test for the null hypothesis 0=γ is 827.21 with 8
degrees of freedom. This is a mixed Chi-squared statistic with a critical value of 15.51
given 8 degrees of freedom. This result means that the inefficiency term should not be
removed from the production function and thus the model will be inconsistently
estimated only using ordinary least squares.
Most of the coefficients in the inefficiency function are significant at the 95% and 90%
confidence intervals. If the coefficient of a variable is negative, it implies that a specific
variable could help technical efficiency improve over time, and has a positive impact on
TFP growth, vice versa. The coefficients of R&D intensity and trade openness have
negative signs and are both significant, which means they are important determinants of
efficiency improvements over time. They usually have great impacts on competition,
specialization, and technology and knowledge transfer as suggested in many other
productivity research studies. The coefficient of regulation impact growth is significant
and positive, which indicates that more restrictive regulations deteriorate technical
efficiency improvement over time and contribute negatively to the TFP growth given the
sample period. Although the human capital term proxied by the share of high-skilled
persons engaged is not statistically significant in the regression analysis, the coefficient
of this term has the expected negative sign, which means with more educated workers in
the labor force, the industry can achieve better production efficiency of applied
technology. The business cycle factor is negative and statistically significant, which
suggests that technical efficiency improvement is more closely related with economic
fluctuations. Coefficients for most of the country dummy variables are negatively
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significant, which indicates the experience of technical efficiency improvements in those
countries.
Detailed decompositions of TFP growth in 13 OECD countries total manufacturing
industries from 1980 to 2004 are reported in Table 2. The first column represents the
annual average TFP growth rate calculated empirically. The industrial gross output
growth is in column 2. The model estimated annual average TFP growth is listed in
column 3. The contributions of technological progress, technical efficiency change and
economies of scale to TFP growth are presented in column 4, 5 and 6 respectively,
followed by the level of average technical efficiency. The model residual can therefore be
calculated by the difference of column 1 and 3.
[Table 2: Average Annual Growth Rate of TFP and its Components (1980-2004) in
selected OECD total manufacturing industries]
All countries’ total manufacturing industries experienced positive TFP growth in the
sample period, in which technological progress contributed most. Therefore technological
progress played a dominant role in contributing to TFP growth. In another words, most of
the TFP growth was due to outward shifts of the production function rather than moves
towards it. The average technical efficiency level is close to one in all sample countries,
indicating that the potential TFP growth will mainly be achieved by technological
progress (innovation). Both the changes in efficiency and economies of scale have
minuscule contributions to TFP growth from the estimation.
The innovation efforts of manufacturing industries differ a lot across the selected
OECD countries. During the study period, Netherlands had the highest technological
growth at a 1.9% annualised rate while Portugal ranked the last at 0.05% annual growth
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in technological progress. The average technological progress is 0.974% per year in the
sample countries manufacturing. Generally speaking, a country experiencing very low
TFP growth such as Portugal should focus on technology innovation along with
improving efficiency to produce. If high rates of technological progress coexisted with
deteriorating technical efficiency in countries like Canada and Italy, then increasing the
efficiency given existing technology is required. For other countries with somewhat
efficiency improvement but relatively low technological progress such as Japan, more
efforts could be put into technology innovations to increase TFP growth over time.
The two countries in North America, Canada and the U.S. did not perform very
competitively in terms of TFP growth across the sample OECD countries. Canadian and
U.S. total manufacturing ranked 8th
and 4th
, respectively, among 13 OECD countries in
average TFP growth. The average TFP growth and its components in Canada were lower
than the 13 OECD country average. Moreover, the TFP growth rate of Canadian total
manufacturing industries was only 57 percent of their U.S. counterparts. Total
manufacturing industries in Canada experienced much slower technology progress than
in the U.S. (60 percent of the U.S.). Negative changes in technical efficiency and
economies of scale also worsened TFP growth in Canada. Canadian manufacturing
experienced lower than OECD average technical efficiency change. As it is well known
that both R&D expenditure is assumed to be a major driver of the fundamental innovation
and efficiency improvement, and ICT capital contributes significantly both directly and
indirectly to TFP growth8, the differences of R&D expenditure and ICT capital share of
total non-residential investment could partly explain the TFP gap between Canadian and
8 ICT capital contributes directly through capital accumulation and capital deepening. They also impact on
innovation indirectly through spillovers effects.
20
the U.S. manufacturing industries. The average ICT share was significantly bigger in the
U.S. than in Canadian manufacturing industries. Canadian manufacturing industries had
less than 10 percent of their U.S. counterparts invested on ICT assets during the sample
period. The R&D share of value-added in Canadian manufacturing industries was only
one third of their U.S. counterparts in 2004. The R&D share averaged 4 percent in
Canada while it averaged 10 percent in the U.S. manufacturing industries. The estimation
results also suggest that the share of high-skilled labor positively contributes to efficiency
improvement. In Canada, the total working hour share of high-skilled persons was only
half of that in the U.S. The difference in labor skills could therefore determine the
difference in TFP growth between these two countries.
To have a closer look at TFP performances in different groups of manufacturing
industries, I also decompose TFP growths in three sub-group manufacturing industries
(low-tech, high-tech and resource-based manufacturing industries) as defined previously.
Overall, the sub-group manufacturing showed similar patterns in terms of the sources of
TFP growth as the total manufacturing. Table 3, Table 4 and Table 5 provide the detailed
summaries for these results.
[Table 3: Average Annual Growth Rate of TFP and its Components (1980-2004) in
Low-tech manufacturing industries]
Across the OECD low-tech manufacturing industries, nearly all TFP growth comes
from technological progress, and both technical efficiency change and economies of scale
contribute negatively to TFP growth. The magnitude of TFP growth in the low-tech
group is much smaller than total manufacturing industries. The U.S. and Canadian low-
tech industries performed relatively competitively in the selected OECD countries,
21
although the TFP growth in Canada was still slightly lower than in the U.S. The total
hours worked by high-skilled persons engaged in Canada were only 60 percent of that in
the U.S. The gap in the R&D expenditure was large and up to 40 percent. These facts
may partly explain the difference in the contribution of technical efficiency to TFP
growth between these two countries.
[Table 4: Average Annual Growth Rate of TFP and its Components (1980-2004) in
High-tech manufacturing industries]
In Table 4, high-tech manufacturing registered the highest average TFP growth in the
sub-group analysis, which posted nearly three times the TFP growth of the low-tech
sector and one and a half times of the resource-based sector. The majority of the TFP
growth was from technology innovation. The high-tech sector played an important role in
the total manufacturing industries across these OECD countries. Average TFP growth in
the Netherlands was nearly five times of that in Portugal. There were five countries
(Netherlands, Italy, U.S., Finland and Sweden) high-tech sector had the above average
technological progress during the sample period. Though this group of manufacturing
experienced rapid technological progress, it was characterized by lower efficiency. This
low level of efficiency was consistent with the estimated contribution of negative
efficiency change to TFP growth. Since many countries experienced negative technical
efficiency change, improving technical efficiency of production given the current
technology could help these countries grow at a higher rate. Canadian high-tech
industries only ranked 10th
out of 13 countries and lagged in TFP growth behind many
other countries. Slower technological progress significantly determined lower TFP
growth in the Canadian high-tech industries. Compared with their U.S. counterparts, TFP
22
growth in Canada was merely 53 percent of that in the U.S. The ICT intensity gap
between Canadian and U.S. high-tech sector was significantly large. The ICT share of
total non-residential investment averaged 8 percent in the U.S., while it was less than one
percent in Canadian high-tech industries. The share of high-skilled persons working
hours in Canada was only 59 percent of that in the U.S. All of these factors may
adversely affect the TFP growth in Canadian high-tech sector.
[Table 5: Average Annual Growth Rate of TFP and its Components (1980-2004) in
Resource-based manufacturing industries]
Table 5 shows the decompositions of TFP growth in resource-based manufacturing
industries. Finland ranked 1st and Japan ranked last in TFP growth. Technological
progress still significantly contributed to TFP growth in this sub-sector. Although
Canadian resource-based manufacturing performed much better than their U.S.
counterparts, it still ranked 8th
out of 13 countries, with lower than average technology
innovation. The change in economies of scale was highest in Canada among all other
OECD countries, while the technical efficiency component negatively contributed to TFP
growth. Canada is known as a natural resource exporting country with comparative
advantage in its natural resource production. Innovation is the most critical driver for
enhanced productivity and competitiveness. To stay in a competitive position, the
Canadian resource-based sector should invest more in ICT capital and human capital,
conduct more R&D and adopt new production process that improve technical efficiency
according to the estimation results.
[Table 6: Average Elasticity Estimates for total manufacturing industries (1980-2004)]
23
Finally, in Table 6, the average contribution from economies of scale to TFP growth is
provided for total manufacturing industries in each country during the period studied. The
elasticities of both types of capital, labor and intermediate inputs for each country are
reported at the average level during the sample periods of 1980-2004. The average ICT
capital share of production was 0.061, the non-ICT capital share was 0.098, the labor
share was 0.168 and the intermediate inputs share was 0.667, which implies constant
returns to scale for production function. This also explains why the component of
economies of scale was minuscule in TFP growth since this component dropped out of
equation (15) when 1=e . Intermediate inputs contributed the most in the production
function since our productivity analysis was based on the gross output method.
V: Conclusion
This paper decomposes total factor productivity growth into technological progress,
efficiency improvement and economies of scale for 13 selected OECD manufacturing
industries, including Canada. This study not only estimates the average TFP growth
across countries, but also investigates the driving forces for productivity growth.
The regression results suggest that the R&D share of value-added, trade openness,
business cycles and smart regulation all have contributed to TFP growth through the
efficiency improvement channel. Overall, TFP growth in 13 selected OECD countries is
mainly due to outward shifts of the production function than to movement towards it.
Intuitively, improvement in efficiency is limited since TFP growth can only be driven to
the production possibility curve; once the production is carried out at the most efficient
level given the existing level of technology, no further improvement in TFP can be
24
achieved. On the other hand, changes in technological progress can be realized over time
and continue infinitely. Thus, once the frontier is reached given the current technology,
long-run growth will come only from technological progress. Changes in economies of
scale and efficiency improvement are minor contributors to TFP growth. The average
total share of capital, labor and intermediate inputs indicates constant returns to scale in
the selected countries’ manufacturing industries. These features of TFP growth and its
sources have shown similar patterns in the three sub-group manufacturing industries
studies.
Canadian manufacturing industries ranked 8 out of 13 OECD countries in terms of
average TFP growth. Moreover, TFP growth in Canada lagged behind the U.S. in most
manufacturing industries, especially in the high-tech manufacturing industries. Canadian
manufacturing industries only had some advantage in the resource-based sectors.
Canadian manufacturing industries experienced just half of the technological progress
compared to the U.S. during the period studied, and they were operating less efficiently
than their U.S. counterparts. The ICT capital intensity, R&D share of value-added gaps
and skills difference between the U.S. and Canadian manufacturing industries were large
and could result in TFP growth gap through innovation and efficiency improvements.
These U.S.-Canada comparative findings are consistent with the recent study by Rao,
Tang, Wang and Hao (2008) of Industry Canada. Their estimates suggest that Canada is
more productive than the U.S. in a number of resource-based industries, but trails the
United States in high-tech manufacturing industries.
The results of this study also point to the importance of efficiency improvements to the
TFP growth given available technologies. In this sense, our study contributes not only to
25
identify the sources of TFP growth which are critical to finding future growth potentials,
but also to practically interpret the effects of policies to promote productivity and
innovation.
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28
Table 1: Estimates of translog production function and inefficiency components
Parameter Variable Estimate Standard Error
Production Function
Beta 0 Intercept 1.103 0.759
Beta 1 ln(KIT) 0.063 0.069
Beta2 ln(KNIT) 0.128 0.171
Beta 3 ln(L) -0.383 0.263
Beta 4 ln(M) 1.191* 0.343
Beta 5 t -0.013* 0.007
Beta 6 ln(KIT)^2/2 -0.006* 0.003
Beta 7 ln(KNIT)^2/2 0.132* 0.022
Beta 8 ln(L)^2/2 0.028 0.030
Beta 9 ln(M)^2/2 -0.032 0.044
Beta 10 t^2/2 0.0005* 0.000
Beta 11 ln(KIT)ln(L) 0.083* 0.015
Beta 12 ln(KNIT)ln(L) -0.035 0.040
Beta 13 ln(KIT)ln(M) -0.013 0.018
Beta 14 ln(KNIT)ln(M) -0.171* 0.057
Beta 15 ln(L)ln(M) 0.237* 0.061
Beta 16 tln(KIT) 0.003* 0.001
Beta 17 tln(KNIT) 0.006* 0.001
Beta 18 tln(L) -0.024* 0.002
Beta 19 tln(M) 0.020* 0.002
Inefficiency Components
Delta 0 Intercept -0.027 0.033
Delta 1 Business cycles -0.163* 0.061
Delta 2 High skilled hours share -0.001 0.014
Delta 3 R&D/VA -1.538* 0.185
Delta 4 Trade openness -0.013* 0.004
Delta 5 Regulation Indicator 0.041* 0.014
Delta 6 Euro-European 0.045* 0.017
Delta 7 Non-Euro European -0.020* 0.017
Delta 8 Oceania -0.065* 0.020
Delta 9 Canada -0.042* 0.019
Sigma square Variance of Inefficiency 0.001* 0.000
Gamma 0.687* 0.079
* denotes significant at both 5% and 10% levels
22
2
vu
u
σσ
σ
+
29
Table 2: Average Annual Growth Rate of TFP and its Components (1980-2004) in
selected OECD total manufacturing industries
TFP
growth
from data
Output
growth
TFP
growth
from
model
Technological
Progress (TP)
Technical
Efficiency
(TE) Change
Economies of
Scale Change
Average
TE (level)
Netherlands 1.991 1.331 1.916 1.915 0.0028 -0.0020 0.9586
Sweden 1.893 2.889 1.553 1.548 -0.0011 0.0058 0.9925
Finland 1.765 3.458 1.467 1.464 0.0002 0.0025 0.9399
USA 1.676 2.138 1.351 1.339 0.0008 0.0111 0.9747
Italy 1.662 2.266 1.266 1.255 -0.0037 0.0147 0.9662
Denmark 1.113 1.584 1.046 1.046 0.0000 0.0003 0.9868
Australia 1.060 1.599 1.034 1.031 -0.0023 0.0054 0.9686
Canada 1.024 2.939 0.778 0.809 -0.0023 -0.0294 0.9652
Germany 0.765 1.528 0.744 0.732 -0.0010 0.0133 0.9859
Austria 0.891 2.596 0.655 0.669 -0.0020 -0.0123 0.9883
UK 0.691 0.426 0.581 0.571 -0.0004 0.0106 0.9854
Japan 0.389 1.932 0.284 0.232 0.0000 0.0519 0.9953
Portogual 0.080 2.374 0.054 0.054 -0.0002 0.0003 0.9414
Average 1.154 2.082 0.979 0.974 -0.0007 0.0055 0.9730
Total Manufacturing Industries
Table 3: Average Annual Growth Rate of TFP and its Components (1980-2004) in Low-
tech manufacturing industries
TFP
growth
from data
Output
growth
TFP growth
from model
Technological
Progress (TP)
Technical
Efficiency
(TE) Change
Economies of
Scale Change
Average
TE (level)
Netherlands 1.647 0.751 1.238 1.252 -0.0004 -0.0134 0.9885
USA 1.307 0.864 0.949 0.967 0.0005 -0.0190 0.9879
Canada 0.855 1.219 0.803 0.812 -0.0001 -0.0088 0.9897
Japan 0.818 0.078 0.688 0.670 -0.0004 0.0189 0.9885
Germany 0.789 0.660 0.619 0.636 0.0002 -0.0173 0.9887
Austria 0.793 0.014 0.537 0.557 0.0002 -0.0205 0.9909
Finland 0.597 0.594 0.396 0.413 0.0004 -0.0172 0.9867
Italy 0.488 1.823 0.322 0.317 -0.0006 0.0061 0.9880
Australia 0.406 0.685 0.272 0.267 -0.0003 0.0056 0.9867
Denmark 0.398 0.649 0.209 0.218 0.0005 -0.0092 0.9865
UK 0.324 0.916 0.202 0.236 0.0003 -0.0351 0.9872
Sweden 0.189 0.164 0.048 0.043 -0.0012 0.0060 0.9860
Portogual 0.145 1.355 0.029 -0.144 -0.0001 0.0039 0.9874
Average 0.674 0.752 0.486 0.480 -0.0001 -0.0077 0.9879
Low-tech Manufacturing Industries
30
Table 4: Average Annual Growth Rate of TFP and its Components (1980-2004) in High-
tech manufacturing industries
TFP
growth
from data
Output
growth
TFP
growth
from
model
Technological
Progress (TP)
Technical
Efficiency
(TE) Change
Economies of
Scale Change
Average
TE (level)
Netherlands 2.611 1.739 2.607 2.599 0.0070 0.0006 0.9625
Italy 1.828 2.474 1.821 1.828 -0.0072 -0.0003 0.9371
USA 1.979 3.092 1.815 1.812 0.0024 0.0002 0.9155
Finland 1.952 5.000 1.810 1.807 0.0066 -0.0039 0.9155
Sweden 1.915 4.385 1.706 1.707 0.0000 -0.0008 0.9742
Denmark 1.377 2.775 1.165 1.165 0.0002 -0.0004 0.9802
Australia 1.173 2.214 1.110 1.113 -0.0027 0.0000 0.9665
Austria 1.086 3.678 1.024 1.028 -0.0015 -0.0028 0.9670
Germany 1.031 2.453 1.002 1.004 -0.0014 -0.0007 0.9711
Canada 1.025 3.574 0.965 0.966 -0.0043 0.0032 0.9503
UK 0.999 1.298 0.892 0.894 -0.0029 0.0005 0.9661
Japan 0.990 3.306 0.605 0.601 0.0007 0.0033 0.9843
Portogual 0.926 3.558 0.562 0.568 -0.0057 0.0005 0.8591
Average 1.453 3.042 1.314 1.315 -0.0007 0.0000 0.9500
High-tech Manufacturing Industries
Table 5: Average Annual Growth Rate of TFP and its Components (1980-2004) in
Resource-based manufacturing industries
TFP
growth
from data
Output
growth
TFP growth
from model
Technological
Progress (TP)
Technical
Efficiency
(TE) Change
Economies of
Scale Change
Average
TE (level)
Finland 1.990 3.015 1.583 1.548 0.0018 0.0333 0.9758
Sweden 1.941 1.485 1.410 1.398 -0.0001 0.0122 0.9851
Italy 1.747 2.307 1.296 1.264 -0.0009 0.0321 0.9791
Germany 1.477 0.665 1.189 1.191 -0.0003 -0.0021 0.9850
Netherlands 1.432 1.082 1.138 1.131 0.0003 0.0067 0.9804
Australia 1.118 1.698 1.025 1.007 0.0001 0.0186 0.9808
Austria 1.118 2.633 0.999 0.957 -0.0005 0.0420 0.9878
Canada 1.218 2.343 0.940 0.892 -0.0001 0.0475 0.9870
Denmark 0.834 0.684 0.807 0.798 0.0001 0.0086 0.9797
UK 0.798 0.230 0.606 0.625 0.0015 -0.0206 0.9797
Portogual 0.753 2.318 0.459 0.541 0.0005 -0.0819 0.9814
USA 0.571 0.847 0.282 0.257 0.0002 0.0244 0.9829
Japan 0.330 0.020 0.229 0.247 0.0000 -0.0185 0.9831
Average 1.179 1.487 0.920 0.912 0.0002 0.0079 0.9821
Resource-based Manufacturing Industries
31
Table 6: Average Elasticity Estimates for total manufacturing industries (1980-2004)
Australia 0.063 0.104 0.181 0.639 0.986
Austria 0.072 0.110 0.199 0.611 0.992
Canada 0.061 0.093 0.162 0.668 0.984
Denmark 0.070 0.117 0.213 0.583 0.983
Finland 0.070 0.111 0.211 0.584 0.975
Germany 0.053 0.090 0.135 0.736 1.013
Italy 0.056 0.089 0.146 0.705 0.996
Japan 0.050 0.077 0.118 0.768 1.013
Netherlands 0.063 0.103 0.191 0.623 0.980
Portugal 0.078 0.110 0.187 0.636 1.011
Sweden 0.060 0.105 0.193 0.617 0.975
UK 0.055 0.091 0.150 0.712 1.008
US 0.043 0.071 0.103 0.794 1.011
Average 0.061 0.098 0.168 0.667 0.994
mlk eee ++
mlk eee ++
mlk eee ++
mlk eee ++
mlk eee ++
mlk eee ++
mlk eee ++
mlk eee ++
mlk eee ++
mlk eee ++
mlk eee ++
mlk eee ++
MeKITe KNITeLe MLKNITKIT eeee +++
Note KITe, KNITe
, Le and Me denotes elasticity of ICT capital, non-ICT capital labor and intermediate
inputs, respectively.
32
Appendix B:
The results of this part were originally derived by Battese and Coelli (1993, 1995) and
rephrased by S.C. Sharma et al. (2007).
Consider the stochastic frontier function:
ℓn Y it = ℓnf(x it , t, β ) + itυ −u it where region i=1, 2,…, m and time t=1, 2,…, T. (a.1)
Let y it = ℓn Y it for simplicity.
Given the assumption of u it (normal distribution truncated at zero) and itυ (normal
distribution), the density function for u it and itυ are:
g 1 (υ ) = πσυ 2
1exp (− 2
2
2 υσυ
), −∞ <υ < ∞ (a.2)
g 2 (u) = )/(2
1
uz σδπσυ Ψ exp (− )2
2
2
)(
u
zu
σ
δ−,u≥0 (a.3)
where Ψ (·) represents the standard normal distribution function for the random
variable and the subscripts, t and i are omitted to ease notation. The joint density of u and
ε is:
h (ε , u) = )/(2
))]}/()(())/())[((2/1(exp{ 2222
uu
u
z
zuu
σδσπσσδσε
υ
υ
Ψ−++−
, u≥0 (a.4)
Simplifying (a.4) gives:
h(ε , u) = )/(2
))]}/()(())/())[((2/1(exp{ 2222*
2*
uu
u
z
zu
σδσπσσσδεσµ
υ
υΨ
+++−− ,u≥0 (a.5)
where *µ = 22
22
υ
υ
σσ
σδεσ
+
+−
u
u z and 2
*σ = 22
22
υ
υ
σσ
σσ
+u
u
(a.6)
From (a.5), the density function of −=υε u is:
h 1 (ε )= ∫∞
0),( duuh ε = )/(2
)]})/()/()/)[((2/1(exp{ 2**
222
uu
u
z
z
σδσσπ
σµσδσε
υ
υ
Ψ
−+−×
π
σµ
2
)))/))((2/1(exp(0
2*
2*∫
∞−− duu
(a.7)
After simplifying, (a.7) becomes:
h 1 (ε )=)}/(/)/({2
)))}(2/))((2/1(exp{
**22
222
σµσδσσπ
σσδε
υ
υ
ΨΨ+
++−
uu
u
z
z (a.8)
Using the (a.5) and (a.8), the conditional density function of u given ε is:
33
f(u|ε )= )/(2
)}/))((2/1(exp{
***
2*
2*
σµσπ
σµ
Ψ
−− u , u≥0 (a.9)
From (a.9), the conditional expectation of exp (−u it ) given itε will be:
TE it = E (e itu− | itε ) = )/(
])/()[(
**,
***,
σµσσµ
it
it
Ψ
−Ψexp ( it*,µ− +
21
*σ ) (a.10)
where we reintroduce the subscripts for clarify the expression for the i-th region at the t-
th period, so (a.6) becomes:
it*,µ = *µ = 22
22
υ
υ
σσ
σδεσ
+
+−
u
ititu z
and 2
*σ = 22
22
υ
υ
σσ
σσ
+u
u
(a.11)
Now the density function for output value y it in (a.1) can be obtained from (a.8):
f(y it ) = )](/)()[(2
)}/(]),,(ln)[2/1(exp{
*,22
222
ititu
uititit ztxfy
ξξσσπ
σσδβ
υ
υ
ΨΨ+
++−− (a.12)
where itξ = u
itz
σδ
, it*,ξ = *
*,
σµ it
, and it*,µ = 22
22)],,(ln[
υ
υ
σσ
βσδσ
+
−−
u
itituit txfyz (a.13)
Let y i = (y 1i , y 2i , ..., y it )’ be a T×1 vector of the log of output of the i-th region and let
y = (y1 ’, y 2 ’, ... , y m ’)’ be the (mT×1) vector of the log of output of all regions over T
time periods. Then the logarithm of the likelihood function of the sample observations y
is given by:
ℓnL (θ, y) = −21 m T [ℓn2π + ℓn ( 22
uv σσ + )]
−21 { ))]}(ln)((ln[ *,
1 1
)),,(ln(22
2
itit
m
i
T
t
ztxfy
u
ititit ξξυσσ
δβ Ψ−Ψ+∑∑= =
+
+− (a.14)
where θ = (β s ’, sδ ’, 2
uσ , 2
υσ )
The log likelihood function in (a.14) will be estimated by Frontier 4.1 software. Using the
estimated parameter values, TE in (a.10) then will be estimated, as well as the
components of TFP growth in equations (9), (10), (11), (12) and (16).