Agricultural productivity change
is explained by many factors. According to Hussain and Perera, (2004) these factors
include: Land and water related factors (such as farm/water course location,
quality of land, sources of water, quality and quantity of water and timing of
water application, etc.), Climatic factors (i.e. rainfall, temperature,
sunshine, frost, etc.), Agronomic factors such as quality, quantity and timing
of input application (i.e. seeds, fertilizers, herbicides, labour, etc.), Socio-economic
factors (such as farmers’ health, education, experience in farming, farm size, tenancy
terms, land fragmentation and availability of credit), Farm management factors
(i.e. adoption of modern production technologies, farm planning and management
practices, etc.).
Some of these factors are interrelated
and the effects of some of them may be much greater than those of others and
there may be locational variations in the degree of their effects on
productivity. Some of these factors may be under the direct control of all the
farmers. Others may be controlled by groups of other farmers, managers at the system
level and policy-makers at higher levels. Yet some of these are beyond human
control (Rahman, 2003). Various other studies have documented some of these
factors. Other factors that abound in economic literature include technology,
labour employment, education and training of farm operators, agro-environmental
conditions, security of land ownership rights and funding which determines the
maximal physical quantity of output that can be reached as well as the number
and quantity of inputs required (Stefanon and Saxena, 1988; Gorton and
Davidova, 2004; Benjamin, 1995; Christiou, 2001; Huffman and Evenson, 2003).
Productivity differences
over time or across farming types can result from variety of factors. These
factors include:
ü Difference in
efficiency (less than the maximum output is produced from a given input
applied);
ü Venation in
scale or level of production over time as the output per unit of input varies
with the scale of production; and
ü Technical change
(Ahearn, Yee, Ball and Nehring, 1998).
Productivity varies over time on
account of the farmer’s rationality in resource use and as a consequent of economic
policies, environment (Kaur, and Sekhon, 2005), infrastructure, cropping systems
and management practices at the plot level.
Concept of Efficiency
The concept of efficiency can be said
to deal with the relative performance of the processes used in the
transformation of inputs into outputs. Economic theory’s discussion of
efficiency distinguishes it into two types; allocative efficiency and technical
efficiency. Farrell (1957) one of the pioneers of efficiency studies
distinguished the two types of efficiency through the use of the frontier
production function (Xu and Jeffrey, 1998). Technical efficiency is defined by
the duo as the ability to produce a given level of output with a minimum
quantity of inputs under certain technology. Allocative efficiency refers to
the ability of choosing optimal input levels for given factor prices. The total
efficiency otherwise called economic efficiency is the product of technical and
allocative efficiency. The degree to which technical and allocative efficiency
are achieved is referred to as production efficiency.
Farm efficiency measurement is very
important both in developed and developing agriculture. Its role in increasing
agricultural output is widely recognized by researchers and policy makers, for
example, Bravo-Ureta and Evenson (1994). There are three distinct approaches to
farm efficiency measurement, while some are based on costs called cost frontier
approach others are based on profit and production function approaches.
Numerous methods have been developed for the empirical measurement of frontier
functions and the potential deviations from such functions. These methods can
be categorized according to the specification of the frontier – parametric or
non-parametric; the way the frontier is computed, through programming or
statistical procedures, and the way deviation from the frontier are
interpreted, that is as inefficiency or a mixture of inefficiency and
statistical noise.
Efficiency is a
very important factor of productivity growth especially in developing agrarian
economies, where resources are meager and opportunities for developing and
adopting better technologies are dwindling. Such economies can benefit from efficiency
studies which show that it is possible to raise productivity by improving
efficiency without increasing the resource base or developing new technologies.
Raising productivity and output of small farmers would not only increase their
incomes and food security, but also stimulate the rest of the economy and
contribute to broad-based food security and poverty alleviation (Lipton, 2005).
Theoretical Framework
The framework for the study is
developed from interplay of the theory of agricultural production, agricultural
programme intervention (Presidential Initiatives on cassava) and technical
efficiency in agricultural productivity. A production function is the technical
relationship between inputs and outputs; that is, a function that summarizes
the process of conversion of factors into a particular commodity. It shows the
maximum amount of the goods that can be produced using alternative combinations
of the various inputs. Pioneering studies that looked at the efficiency of
farms are those by Koopman (1951) and Farrell (1957). The relevance of
efficiency in increasing agricultural production has been widely recognized and
variously investigated by researchers such as Bravo-Ureta, (1993); Ashok et
al., (1995); Seyoum, (1998); Abay, Miran and Gunden, (2004); Chavas, Petrie
and Roth, (2005).
Empirical Review of Related Literature
A
study by Battese and Coelli (1995) on paddy rice farms in Aurepalle India used
panel data for 10 years and concluded that older farmers were less efficient
than the younger ones. Farmers with more years of schooling were also found to
be more efficient, but this declined over time; this is expected as farmers
grow older the energy to do the tedious farm activities tend to decrease with
age. Battese et al., (1996) used a single stage stochastic frontier
model to estimate technical efficiency in the production process of wheat
farmers in the four districts of Pakistan, the result obtained ranged between
57 and 79 percent. According to them the older farmers had smaller technical
inefficiencies as expected. Seyoum et al., (1998) in measuring technical
efficiency of maize farmers in Eastern Ethiopia for farmers within and outside the
Sasa-kawa Global 2000 project used a translog stochastic production function
and a Cobb-Douglas production function. One of their conclusions is that
younger farmers are more technically efficient than the older farmers; also
farmers with more years of schooling tend to be more efficient. Those who
received more extension information tended to reduce technical in-efficiency
the more. The mean technical efficiency of farmers within the SG 2000 project
was estimated to be 0.94 while farmers outside the project had 0.79.