An analysis of production relations in the large-scale textile manufacturing sector of Pakistan.
Malik, Sohail J. ; Mushtaq, Mohammad ; Nazli, Hina 等
This paper attempts to determine econometrically the underlying
production relations for the large-scale textile manufacturing sector of
Pakistan, based on data available from the six most recent censuses of
large-scale manufacturing industries. The covariance model is used for
pooling the provincial data. Testing for alternative forms reveals that
the CES production function with constant-returns-to-scale most
adequately explains the underlying production structure. The estimates
of the elasticity of substitution are significantly different from zero
in all cases, implying significant and efficient employment generation
possibilities.
INTRODUCTION
The strategy underlying Pakistan's development during the
earlier decades was based on the concept of "industrial
fundamentalism". A host of fiscal, trade, financial and
technological policies were implemented to encourage the process of
growth through industrialization. However, it was observed that the
process of industrialization brought in increasingly capital-intensive
techniques of production. There are two schools of thought as to why
this occurs. The "technological determinists" believe that
technical efficiency alone determines the eventual choice of technique
and since the technically efficient techniques are also the
capital-intensive ones, the norms of efficiency dictate continuous
capital-deepening in production. No choice of technique is possible, in
this view, because the elasticity of factor-substitution is zero or near
zero. On the other hand, the "neo-classicists" maintain that
factor-substitution is possible, and that it is the factor-price
distortions created by a host of incentive policies pursued which
generate an inoptimal choice of capital-intensive techniques. The
large-scale textile manufacturing industry in Pakistan is a prime
example of such an "industrial fundamentalism". A host of
Government incentives were directed at promoting the growth of this
sector. However, the growth in employment did not keep pace with the
growth in output. Moreover, a continuing process of capital-deepening
was observed. Which of the two diverse theoretical propositions outlined
above explain this phenomenon?
This study seeks to evaluate these two points of view, through an
in-depth investigation of the possibilities of factor-substitution in
the large-scale textile manufacturing sector of Pakistan. The study sets
out to test a number of other hypotheses that have a direct bearing on
the eventual estimate of the elasticity of substitution. Since the data
are available at the provincial level, initially we test the hypothesis
of the similarity of provincial functions. Only if such functions are
similar can we pool the data to obtain estimates for Pakistan as a
whole. If the provincial functions are different, it implies a
difference in the underlying production relations in this sector across
the provinces. Having determined if pooling of data is possible or not,
we then proceed to test the hypothesis of the similarity of functions
over time. The results of this test also, in addition to providing
possible validity for pooling the successive cross-sections, provide us
with an insight into the changes in the production relations over time.
The basic thrust of the paper is a series of tests designed to show
which functional form best fits the data or, in other words, adequately
explains the underlying production relations. As is well known, various
generalizations of the basic (indirect) estimating forms of the CES
production function are available, which permit testing for the
existence of variable-returns-to-scale. Moreover, extensions that permit
variable elasticities of substitution as well as variable returns to
scale are also available, and are estimated. These forms and the testing
procedure are descried in detail in the section on methodology.
The large-scale textile manufacturing sector is of considerable
importance to Pakistan not only because it is the predominant industrial
sub-sector, but also because of its backward linkages with the key
agricultural sector. The results of this study could be of considerable
interest for policy-making. In a labour-abundant, capital-scarce economy
like Pakistan's, the existence of significant factor-substitution
possibilities in textile manufacturing will imply increased employment
generation without sacrificing efficiency (i.e., without loss of
output).
To date, there has been very little work done in this area. Three
previous studies of note, however, must be mentioned. The first, by Kazi
et al. (1976), using the constant elasticity of substitution production
function, found the possibilities of labour capital substitution to be
limited in the large-scale textile manufacturing sector. The second
study, by Kemal (1981), using an adjusted or "consistent"
time-series data, also found limited possibilities of
factor-substitution in this sector. However, a recent study, by Battese
and Malik (1987), has found significant possibilities of
factor-substitution using aggregative data for selected key industries.
This study has highlighted the need for disaggregated analysis of the
key industries, including textiles.
The decline over time of relative importance of the textile
industry in Pakistan can be gauged from the following statistics. During
the period from 1970-71 to 1980-81 the mean value of the proportion of
value added in large-scale industries combined was 0.22. This proportion
declined from a maximum of 0.30 in 1970-71 to 0.16 in 1980-81. The mean
value of employment in this industry as a proportion of total
large-scale industrial employment was 0.46. This proportion ranged from
a maximum of 0.48 in 1970-71 to a minimum of 0.41 in 1980-81. The trend
value of the regression of time variable on the log of real value added
(1) in this sector shows that it declined at a rate of 0.48 percent.
Moreover, employment in this sector declined at a rate of 0.71 percent
while real capital employed declined at a rate of 1.04 percent.
Employment cost as a proportion of value added in this industry,
however, grew at a rate of 2.90 percent. This was due partly to the
growth of wages of 3.13 percent and partly because of the decline in
value added.
An examination of the sub-sectors within the large-scale textile
manufacturing sector reveals that, in terms of the value added generated
and the capital and labour employed, it is heavily dominated by
cotton-spinning and weaving and finishing of cotton textiles. These
categories together account for over seventy percent of the value added,
seventy-five percent of the capital employed, and nearly the same
percentage of the labour employed. However, spinning of cotton is a more
capital-intensive industry requiring a higher proportion of capital per
unit of labour to produce the same proportion in value added. It is the
trends in these two categories that have dominated the trends in the
overall textile sector. The growth rates of different key variables in
the constituent categories and in overall textile manufacturing can be
seen in Table 1.
The study is divided into five sections. Details of the methodology
and the procedures followed are described in the next section. The data
used are described in the third section, while the results are presented
in the fourth section. The summary of contusions makes up the last
section.
METHODOLOGY (2)
We start by specifying a simple Constant Elasticity of Substitution
(CES) production function with only two factors, of production capital
and labour. (3) It can be shown easily that when the elasticity of
substitution is one, the function represents a Cobb-Douglas type
production function; moreover, when it is zero, the function represents
a Leontief type fixed factors situation [Chiang (1984)].
Parameters of the constant--or variable-elasticity-of-substitution-
production functions are estimated by considering their indirect forms,
which are derived under the assumption that the marginal productivity of
labour is equal to the wage rate. These functions are specified for
firms in different asset-size categories. Given that the input levels of
firms within these different asset-size categories are the same [see
Battese and Malik (1986)], the appropriate indirect form of the
variable-returns-to-scale, constant-elasticity-of-substitution (CES)
production function is:
Log ([[bar.Y].sub.i] / [L.sub.i]) = [[beta].sub.0] + [[beta].sub.1]
Log [W.sub.i] + [[beta].sub.2] Log [L.sub.i] + Log [[bar.V].sub.i] ...
(1)
i = 1,2,......., n:
where [[beta].sub.1][equivalent to] v[(v + [rho]).sup.-1] and
[[beta].sub.2] = [rho] (v-1)[(v + [rho]).sup.-1] =
(v-1)(1-[[beta].sub.1]);
v is the homogeneity (return-to-scale) parameter;
[rho] is the substitution parameter;
[[bar.Y].sub.1] represents the sample mean of value added for the
firms in the ith asset-size category;
[L.sub.i] represents the number of labourers employed by firms in
the ith asset-size category; and
[W.sub.i] represents the wage rate for labourers in firms within
the ith asset-size category.
log [[bar.Y].sub.i] has an approximately normal distribution with
variance inversely proportional to the number of firms within the ith
asset-size category represented by [T.sub.i], provided that the number
is sufficiently large; and n represents the number of asset-size
categories involved.
It is readily verified that the elasticity of substitution, o, is
expressed in terms of the coefficients of the logarithms of wages and
labour in (1)by
[sigma] = [[beta].sub.1] [(1 + [[beta].sub.2]).sup.-1]
Thus, if the constant-returns-to-scale CES production function
applies (i.e. v = 1), then the coefficient of the logarithm of labour,
[[beta].sub.2], is zero and so the coefficient of the logarithm of
wages, [[beta].sub.1], in the indirect form (1), is equal to the
elasticity of substitution. In this case the estimable indirect form is
Log ([[bar.Y].sub.i] / [L.sub.i]) = [[beta].sub.0] + [[beta].sub.1]
Log [W.sub.i] + Log [[bar.V].sub.i] ... ... ... ... ... (2)
i = 1,2,......,n.
The indirect form of the variable-returns-to-scale VES production
function is
Log ([[bar.Y].sub.i] / [[bar.L].sub.i]) = [[beta].sub.0] +
[[beta].sub.1] Log [W.sub.i] + [[beta].sub.2] Log ([K.sub.i] /
[L.sub.i]) + [[beta].sub.3] Log [L.sub.i] + Log [[bar.V].sub.i], (3)
i = 1, 2,......n;
where [[beta].sub.1] [equivalent to] v[(v + [rho]).sup.-1],
[[beta].sub.2] [equivalent to] c and [[beta].sub.3] [equivalent to] v-1
If the returns-to-scale parameter, v, is one (i.e.,
constant-returns-to-scale applies), then it is clear from the above that
[[beta].sub.3] is zero and the indirect form is
Log ([[bar.Y].sub.i] / [L.sub.i]) = [[beta].sub.0] + [[beta].sub.1]
Log [W.sub.i] + [[beta].sub.2] Log ([K.sub.i] / [L.sub.i]) + Log
[[bar.V].sub.i] ... (4)
i = 1,2,......n;
Further, if [[beta].sub.2] = 0 in model (4) or [[beta].sub.2] = 0
and [[beta].sub.3] = 0 in model (3), then the indirect form of the
constant-returns-to-scale CES production function (2) is obtained.
Given that the random errors, Log [[bar.V].sub.i], i = 1, 2,....n,
in the indirect forms, (1) - (4), are heteroscedastic and the variances
are proportional to the number of firms within the corresponding
asset-size categories, then the parameters are most efficiently
estimated by weighted least-squares regression. In fact, the generalized least-squares estimators for the parameters are obtained by ordinary
least-squares regression after the values of the variables in the
indirect forms are multiplied by the square root of the corresponding
number of firms within the given asset-size category (i.e., the ith
observations of the variables in the appropriate indirect form are
multiplied by [r.sup.1/2.sub.i]).
Given that appropriate regularity conditions are satisfied [see
Battese and Malik (1986)], it follows that:
(i) The t-statistic associated with the weighted least-squares
estimator of [[beta].sub.2] in model (1) has approximately [t.sub.(n-3)]
distribution if the constant-returns-to-scale CES production function
applies;
(ii) The F-statistic associated with the weighted least-squares
estimators of [[beta].sub.2] and [[beta].sub.3] in model (3) has
approximately [F.sub.(2, n-4)] distribution if the
constant-returns-to-scale CES production function applies; and
(iii) The t-statistic associated with the weighted least-squares
estimator of [[beta].sub.3] in model (3) has approximately [t.sub.(n-4)]
distribution if the constant-returns-to-scale VES production function
(4) applies.
A consistent estimator of the elasticity of substitution for the
constant-returns-to-scale VES production function is defined by
[MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII]
where [[??].sub.1] and [[??].sub.2] represent the generalized
least-squares estimators for the parameters, [[beta].sub.1] and
[[beta].sub.2], in the indirect form (4); and
[member of] [equivalent to] (wL + rK)/rK is the ratio of total
factor costs to the cost of capital.
If the econometric models considered above are defined for several
time-periods, then the most general situation, for which a particular
model applies, involves the variables and parameters being indexed by
the time-periods involved. It can be shown that it is meaningless to
discuss the estimation of the elasticity of substitution on the basis of
aggregative time-series data unless we assume that the elasticities are
the same for all time-periods. (4) Additionally, if firm-level data are
not available for the T time-periods and only totals of value added,
wages, capital and. labour are available for each time-period, then the
elasticity of substitution is estimable from aggregative time series
data, if the following restrictive conditions on the original production
functions hold:
(1) Wages and labour inputs are the same for all firms at any given
time-period, i.e., [w.sub.tij] = [w.sub.t] and [L.sub.tij] = [L.sub.t]
for all
j = 1, 2,.......[r.sub.ti]; i = 1,2,.....[n.sub.t]; t = 1,
2,......T;
(2) The substitution parameters, [[rho].sub.t], t = 1,
2,.........T, are the same and hence the elasticity parameters, [(1 +
[rho]).sup.-1], t = 1,2..........T, are the same over time.
Given that the above conditions are satisfied for the aggregative
cross-sectional data for each time-period, the relevant indirect forms,
associated with the CES production functions [Equation: 2 with
[[beta].sub.2] = 0] are defined by:
Log ([[bar.Y].sub.ti] / [L.sup.ti]) = [[beta].sub.t0] +
[[beta].sub.t1] Log [w.sub.ti] + Log [[bar.v].sub.ti], ... ... (5)
i = 1,2,......[n.sub.t]; t = 1, 2,.......T,
where [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] is the
sample mean of value added for the reporting firms in the ith asset-size
category in the tth time-period; and log [[bar.v].sub.ti] has an
approximately normal distribution with mean 1/2 [[sigma].sup.2.sub.u]
and variance [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII], if the
number of reporting firms in the ith asset-size category in the tth
time-period is sufficiently large.
Given the indirect form (5), the hypothesis that the slope
parameters are equal (i.e., [[beta].sub.t1] = [[beta].sub.1] for all t =
1, 2, .... T) is testable by traditional regression methods, which do
not require that the intercept parameters, [[beta].sub.t0], t = 1,
2,......T, satisfy any functional relationship. Further, it is possible
to test the hypothesis of Hicksian neutral technological change (i.e.,
[[beta].sub.t0] = [[beta].sub.0] + [[delta].sub.0] t and [[beta].sub.t1]
= [[beta].sub.1] for all t = 1, 2,.....T), given the indirect form (5).
Suppose that, for a given industry, the constant-returns-to-scale
VES production function [Equation 4] holds for the different
time-periods involved. Then the estimable indirect forms of the VES
production functions involved are defined by:
Log ([[bar.Y].sub.ti] / [L.sub.ti]) = [[beta].sub.t0] +
[[beta].sub.t1] log [w.sub.ti] + [[beta].sub.t2] log [K.sub.ti] /
[L.sub.ti]) + log [[bar.v].sub.ti], ... (6)
i = 1,2,.....[n.sub.t]: t = 1,2,......T.
Given the definition of the elasticity of substitution for this VES
model, it follows that if the ratio of factor costs, e, is constant for
the time-periods involved, then the elasticity is only constant over
time if the coefficients [[beta].sub.t1] and [[beta].sub.t2] of the
logarithms of wages and the capital-labour ratio in the indirect form
(6) are constant over time. Test procedures can be devised for this
hypothesis, using traditional regression methods for the estimation of
the indirect form (6).
Suppose that the elasticity of substitution for the
constant-returns-to-scale VES production function is constant over time.
It is, then, evident that the estimation of the elasticity by use of
aggregative time-series data requires that the wages and labour and
capital inputs be the same for all firms at any given time-period. Such
conditions are obviously very unrealistic.
It is also evident that difficulties similar to those indicated
above apply to the estimation of elasticities when related products are
aggregated to obtain a composite product, such as the textiles. This
emphasises the desirability of obtaining data at the firm level, for
well-defined products, within the time-periods of interest.
DATA
Data on the different aspects of Pakistan's large-scale
manufacturing firms can be obtained from the census of large-scale
manufacturing industries. The census data suffer from three main
defects:
1. There is serious undercoverage of the firms involved;
2. They are not available on a yearly basis; and
3. The definitions of some variables have changed over time. (5)
They are discussed in detail in Kemal (1976).
However, in the absence of an alternate data set, we use the
original published data from the census of large-scale firms within the
large-scale textile industry for each year for the years 1969-70,
1970-71, 1975-76, 1976-77, 1977-78 and 1980-81 [Government of Pakistan (1973), (1977), (1980), (1982), (1983) and (1984)]. These years are the
six most recent years for which data are available in published form.
These data in aggregate form are available in cross-tabulations, across
asset-size categories for the provinces of Punjab and Sind. Our
analysis, therefore, concentrates only on the data from these two
provinces. The total number of observations for each province in the
respective year are presented in Table 2.
RESULTS
The results reported in this section follow a systematic pattern,
as we proceed step-wise to determine the functional form that most
adequately explains the underlying data and then report the elasticity
estimates based on this selected estimating form. It bears repeating
that the form that most adequately represents the data is in fact
portraying the underlying production relations in the large-scale
textile manufacturing sector of Pakistan.
Initially we consider the possibilities of the similarity of the
province functions. Tests are conducted on the basis of three hypotheses
for both the constant-returns-to-scale and variable-returns-to-scale
versions of the CES and VES production functions. Three hypotheses are
considered, namely:
1. The province functions have the different intercepts but same
slopes;
2. The province functions have the same intercepts but different
slopes: and
3. The province functions are different, i.e., both intercepts and
slopes.
The relevant test statistics have approximate F distribution and
are presented in Tables 3 and 4. A perusal of these tables shows that
the hypothesis of dissimilarity is accepted in only 7 of the 72 cases
(i.e., approximately 10 percent of the cases). We, therefore, can
proceed with reasonable confidence to pool the data of the two
provinces. Next we consider the possibility that the yearly functions
for each of the versions of the CES and VES production functions are
similar. Here, again, we consider the three possibilities of each case:
1. Yearly functions have different intercepts but the same slopes;
2. Yearly functions have the same intercepts but different slopes;
and
3. Yearly functions are different, i.e., both slopes and
intercepts.
A perusal of Table 5 shows that the yearly functions are
dissimilar. All the test statistics reported in this table are
significant.
At the third stage we conducted tests to determine the adequacy of
different functional forms, given that the constant-returns-to-scale CES
production function applies. The relevant test statistics are presented
in Tables 6 to 8. The tests reveal that in majority of cases the
constant-returns-to-scale CES production function adequately explains
the underlying data, because the null hypothesis that the CRS, CES
production function applies is rejected in 4 of the 18 cases.
On the assumption that the CES-CRS production function applies, the
computed elasticities of substitution are presented in Table 9. Tiffs
table also presents t-statistics for the tests that the computed
elasticities are different from unity. The estimated elasticities are in
all cases significantly different from zero. There is an interesting
pattern in which the estimated elasticity increases from 0.43 in 1969-70
to 2.37 in 1980-81. The estimates are not significantly different from
One in 1975-76, 1976-77 and 1977-78. In all other cases the elasticities
are significantly different from One.
The careful testing procedure adopted in this study has yielded
several results. Firstly, the underlying production structures are
similar in the two provinces in the different census years. However,
there is significant dissimilarity across years. Secondly, the
production relations are characterized by a constancy in the elasticity
of factor substitution. Thirdly, for each of the census years examined,
constant returns-to-scale applied generally. And, lastly, there are
significantly greater possibilities of factor substitution in this
sector than were thought possible on the basis of previous studies. [See
Kazi et al. (1976) and Kemal (1981)].
CONCLUSIONS
The study sets out to test a number of hypotheses that have a
bearing on the eventual estimate of the elasticity of substitution.
Initially, we test the hypothesis of the similarity of provincial
functions. Only if such functions are similar can we pool the data to
obtain estimates for Pakistan as a whole. If the provincial functions
are different, it implies a difference in the underlying production
relations in this sector across the provinces. Having determined if
pooling of data is possible or not, we then proceed to test the
hypothesis of the similarity of functions over time. The results of this
test also, in addition to providing a possibly valid step for pooling
the successive cross-sections, provide us with an insight into the
changes in the production relations over time. The basic thrust of the
paper is a series of tests designed to show which functional form best
fits the data, or, in other words, must adequately explain the
underlying production relations.
There has been very little work done in this area to date. Previous
studies had found the possibilities of labour-capital substitution to be
rather limited in this industry. [See e.g., Kemal (1981) and Kazi et al.
(1976)].
The testing procedure adopted in this study has yielded several
useful results. Firstly, the underlying production structures are
similar, in the two provinces in the different census years, although
there is significant dissimilarity across years. Secondly, the
production relations are characterized by a constancy in the elasticity
of factor substitution. Thirdly, for each of the census years examined,
constant-returns-to-scale applied generally. And, lastly, there are
significantly greater possibilities of factor substitution in this
sector than were thought possible on the basis of previous studies.
However, the aggregate analysis hides a number of problems that would
appear in analysis at a more disaggregate level. Such a study is highly
warranted. There is a need, especially, to study the weaving and
finishing of cotton textiles separately. This would require data at the
firm-level. The Government of Pakistan had in 1978 commissioned a
massive study of the cotton textile industry of Pakistan [Werner (1978)]
which highlighted the problems in different categories of the textile
sector. Unfortunately, these recommendations have not been implemented
completely. The consultants have noted that similar recommendations were
made as far back as the 1950s to the same end.
Our study highlights an important problem. At the aggregate level
the elasticity of factor substitution is positive. Yet, for a
labour-abundant capital-scarce economy like Pakistan, employment
continues to decline in textile manufacturing. Does this say anything
about relative factor prices? Is it not time that we focus our attention
on the hitherto unforeseen effects of policies designed to distort
factor prices.
Authors' Note: We would like to thank Professor Syed Nawab
Haider Naqvi, Director, and Dr Sarfraz Khan Qureshi, Joint Director of
the Institute, for their valuable guidance and support. The excellent
typing support of Mr Mohammad Yousaf is also gratefully acknowledged.
REFERENCES
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Estimation of Elasticities of Substitution for Firm-level Production
Function using. Aggregative Data Working Papers in Econometrics and
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England, Armidale.
Battese, G. E., and S. J. Malik (1987) Estimation of Elasticity of
Substitution for CES Production Functions using Data on Selected
Manufacturing Industries in Pakistan Pakistan Development Review XXVI:2
161-178.
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Possibilities of Employment Generation in the Large-scale Food
Processing Sector in Pakistan Paper presented at the Australian Economic
Congress, Canberra.
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1969-70. Karachi: Ministry of Finance Planning and Development,
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Pakistan, Government of (1977) Census of Manufacturing Industries,
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(1) The growth rates are computed from the following regressions:
Log (Y) = [varies] +/[beta]T, where is the trend coefficient, and T
denotes time. All estimated coefficients, unless otherwise stated, are
significant at 5 percent level. The growth rates are based on the
available Census of Manufacturing Industries data for the period 1969-70
to 1980-81.
(2) This section relies heavily on Battese, Malik and Babar (1988).
(3) It is possible, of course, to include a number of inputs and/or
types of labour and capital in the specification. However, data
availability constrains us to use the simple specification.
(4) This is not to deny the importance of analysis from time-series
data but simply to highlight a basic assumption, often forgotten, when
estimating from this type of data.
(5) An example of the changing definitions of key variables in
different censuses is the fixed assets. Prior to 1962-63, the censuses
reported the written-down values of capital at the end of the year as
fixed assets. Since 1962-63, the censuses have used written-down values
at the beginning of the year, plus any investments during the year, but
with no deductions made for any depreciation during the year.
SOHAIL J. MALIK, MOHAMMAD MUSHTAQ and HINA NAZLI *
* The authors are, respectively, Research Fellow at the
International Food Policy Research Institute, Washington, D.C. and Staff
Economists at the Pakistan Institute of Development Economics,
Islamabad.
Table 1
Growth Rates of Different Sub-sectors within the Textile
Industry of Pakistan from 1970-71 to 1980-81
(1959-60 prices)
S W SWWSE CRW MT
N 1.05 -2.61 4.80 -3.93 2.67
L 3.13 -5.19 0.96 0.09 -2.47
W 2.84 3.64 1.60 -1.36 1.46
K 1.76 -4.56 -0.09 4.51 -2.59
EC 5.96 -1.55 2.56 -1.28 -1.01
VA 2.60 -7.0l 3.90 8.37 4.77
EC/VA 3.36 5.46 -1.34 -9.65 -5.78
VA/L -0.52 -l.82 2.94 8.29 7.24
DBF SWFN SWJE Overall
N 5.59 -1.34 2.40 2.58
L 1.70 -1.25 1.96 -0.71
W 3.18 2.12 5.46 3.13
K -3.45 2.30 0.17 -1.04
EC 4.88 0.87 7.42 2.42
VA 1.23 6.38 7.96 -0.48
EC/VA 3.64 -5.5 -0.54 2.90
VA/L -0.46 7.62 6.00 0.23
Source: Based on Census of Manufacturing Industries (Various Issues).
Notes: Growth rates of VA, EC, W and K based on deflated data
S = Spinning of cotton.
W = Weaving and Finishing of cotton textiles.
SWWSE = (i) Spinning, Weaving and Finishing of woollen textiles
except hand-looms.
(ii) Spinning, Weaving and Finishing of silk and art-silk
and synthetic textiles except hand-looms.
CRW = Carpet and rugs--wool.
MT = (i) Made up textile goods except wearing apparel.
(ii) Knitting mills.
DBF = Dying, bleaching and finishing of textiles only.
SWFN = (i) Spinning, weaving and finishing of narrow fabrics.
(ii) Spooling and thread-ball making.
SWJE = (i) Spinning, weaving and finishing of jute textiles
except hand-looms.
(ii) Cordage, rope and twine.
(iii) Manufacture of textiles n.e.c.
(iv) Others.
N = Number of firms.
L = Labour employed.
W = Wage rate.
K = Capital employed.
EC = Employment cost.
VA = Value-Added.
EC/VA = Employment cost as a proportion of Value-Added.
VA/L = Value-Added per worker.
Table 2
Number of Observations in Different Years for the
Textile Industry in Various Censuses of the
Manufacturing Industries
Years Punjab Sind Total
1969-70 12 13 25
1970-71 6 13 19
1975-76 7 7 14
1976-77 7 7 14
1977-78 7 7 14
1980-81 7 7 14
Total 46 54 100
Note: The observations are based on the asset-size
categories for each province in the corresponding years.
Table 3
Test Statistics for the Similarity of Province Functions--the
Case of CES Production Function with Constant-Returns-to-Scale
(CRS) and Variable Returns-to-Scale (VRS)
Production
Function 1969-70 1970-71 1975-76
CES-CRS
[F.sub.1] 1.43 0.21 1.60
(1,22) (1,16) (1,11)
[F.sub.2] 1.57 1.79 5.35 **
(1,22) (1,16) (1,11)
[F.sub.3] 0.82 2.98 2.48
(1,22) (2,15) (2,10)
CES-VRS
[F.sub.1] 3.43 0.23 3.02
(1,21) (1,15) (1,10)
[F.sub.2] 0.97 4.61 ** 2.40
(2,20) (2,14) (2,9)
[F.sub.3] 2.26 4.67 ** 1.65
(3,19) (3,13) (3,8)
Production
Function 1976-77 1977-78 1980-81
CES-CRS
[F.sub.1] 2.97 4.21 1.72
(1,11) (1,11) (1,11)
[F.sub.2] 0.08 0.10 1.14
(1,11) (1,11) (1,11)
[F.sub.3] 2.88 3.36 1.45
(2,10) (2,10) (2,10)
CES-VRS
[F.sub.1] 1.62 0.76 0.06
(1,10) (1,10) (1,10)
[F.sub.2] 0.84 0.34 4.50 **
(2,9) (2,9) (2,9)
[F.sub.3] 0.91 0.58 2.63
(3,8) (3,8) (3,8)
Notes: ** Indicates Significant at 5 percent level.
(i) The figures in parentheses are degrees of freedom.
(ii) The figures given in the rows [F.sub.1], [F.sub.2] and [F.sub.3]
are the approximate values of F-statistics computed under three
hypotheses reported on page 36.
Table 4
Test Statistics for the Similarity of Province Functions--the
Case of VES Production Function with Constant-Returns-to-Scale
(CRS) and Variable Returns-to-Scale (VRS)
Production
Function 1969-70 1970-71 1975-76
VES-CRS
[F.sub.1] 1.50 0.11 0.83
(1,21) (1,15) (1,10)
[F.sub.2] 0.74 4.49 ** 1.03
(2,20) (2,14) (2,9)
[F.sub.3] 0.49 3.37 1.79
(3,19) (3,13) (3,8)
VES-VRS
[F.sub.1] 3.72 0.14 1.03
(1,20) (1,14) (1,9)
[F.sub.2] 1.47 3.81 ** 1.98
(3,18) (3,12)
[F.sub.3] 1.73 3.40 1.38
(4,17) (4,11) (4,6)
Production
Function 1976-77 1977-78 1980-81
VES-CRS
[F.sub.1] 3.60 3.37 0.67
(1,10) (1,10) (1,10)
[F.sub.2] 1.74 1.44 2.90
(2,9) (2,9) (2,9)
[F.sub.3] 5.16 ** 3.77 1.70
(3,8) (3,8) (3,8)
VES-VRS
[F.sub.1] 2.40 0.10 0.14
(1,9) (1,9) (1,9)
[F.sub.2] 2.69 0.33 2.70
(3,7) (3,7) (3,7)
[F.sub.3] 2.20 0.40 2.02
(4,6) (4,6) (4,6)
Notes: ** Indicates Significant at 5 percent level.
(i) The figures in parentheses are degrees of freedom.
(ii) The figures given in the rows [F.sub.1], [F.sub.2]
and [F.sub.3] are the approximate values of F-statistics
computed under three hypotheses reported on page 36.
Table 5
Test Statistics for the Stability of Yearly Function--the
Case of CES and VES Production Function with
Constant-Returns-to-Scale (CRS) and Variable-Returns-to-Scale (VRS)
Production
Function [F.sub.1] [F.sub.2] [F.sub.3]
CES-CRS 2.95 * 9.96 * 5.84 *
(5,92) (5,92) (10,87)
CES-VRS 3.58 * 7.64 * 6.06 *
(5,91) (10,86) (15,81)
VES-CRS 3.52 * 5.68 * 4.21
(5,91) (10,86) (15,81)
VES-VRS 3.86 * 5.12 * 4.87 *
(5,90) (15,80) (20,75)
Notes: * Indicates Significant at 1 percent level.
(i) The figures in parentheses are the degrees of freedom.
(ii) The figures in columns [F.sub.1], [F.sub.2] and [F.sub.3]
are the approximate values of F-statistics computed under
the three assumptions given on page 36.
Table 6
Test Statistics for the Adequacy of the Variable-Returns-to-Scale
CES Production Functions, given that Constant-Returns-to-Scale CES
Production Functions Apply
Years 1969-70 1970-71 1975-76
Coefficient
of Log (L) 0.006 0.001 0.001
T-statistics (1.51) (0.18) (0.47)
Years 1976-77 1977-78 1980-81
Coefficient
of Log (L) -0.003 -0.007 -0.009
T-statistics (-1.53) (-3.12) ** (-1.86)
Note: ** Denotes Significant at 5 percent level.
Table 7
Test Statistics for the Adequacy of the Constant-Returns-to-Scale
VES Production Functions, given that Constant-Returns-to-Scale CES
Production Equations Apply
Years 1969-70 1970-71 1975-76
Coefficient
of Log (K/L) -0.012 -0.023 -0.298
T-statistics (-0.19) (-0.32) (-2.99) **
Years 1976-77 1977-78 1980-81
Coefficient
of Log (K/L) -0.102 -0.142 -0.253
T-statistics (-0.11) (-0.61) (-0.95)
Note: ** Denotes Significant at 5 percent level.
Table 8
Test Statistics for the Adequacy of Variable-Returns-to-Scale
VES Production Functions, given that Constant-Returns-to-Scale
CES Production Functions Apply
Years 1969-70 1970-71 1975-76
[F.sub.1] 1.496 0.055 4.10 **
d.f. ([V.sub.1],
[V.sub.2]) (2,21) (2,15) (2,10)
Years 1976-77 1977-78 1980-81
[F.sub.1] 1.247 5.933 ** 1.824
d.f. ([V.sub.1],
[V.sub.2]) (2,10) (2,10) (2,9)
Notes: ** Denotes Significant at 5 percent level.
[F.sub.1] = The statistics in this row are the approximately F
random variables with d.f. [V.sub.1] and
[V.sub.2] = given that functions are not different from
Constant-Returns-to-Scale CES Production Functions.
Table 9
Estimates of Elasticity of Substitution given that the
Constant-Returns-to-Scale CES Production Functions Apply,
and the Test Statistics for the Hypothesis that the
Elasticity is Different from Unity
Years [??] [T.sub.1] d.f.
1969-70 0.43 2.31 ** 23
(1.756) ***
1970-71 0.45 2.360 ** 17
(1.932) ***
1975-76 0.89 0.668 12
(5.412) *
1976-77 1.30 1.537 12
(6.538) *
1977-78 1.28 1.434 12
(6.56) *
1980-81 2.37 2.031 ** 11
(3.512) *
Notes: The figures in parentheses are t-values of the given
estimate.
* Denotes Significant at 1 percent level.
** Denotes Significant at 5 percent level.
*** Denotes Significant at 10 percent level.
[T.sub.1] = The Statistics in this column are absolute t-values
under null hypothesis that the elasticity of substitution is
equal to unity.