stochastic frontier analysis, statistical analysis by jairus ounza muhehe, [email protected]
TRANSCRIPT
PROFIT EFFICIENCY AMONG RICE PRODUCERS IN EASTERN AND
NORTHERN UGANDA
BY
HYUHA THEODORA SHUWU
BA ECONOMICS (SIMON FRASER UNIVERSITY, CANADA)
MSC. AGRIC ECONOMICS (UNIVERSITY OF ALBERTA, CANADA)
A THESIS SUBMITTED TO THE SCHOOL OF GRADUATE STUDIES FOR
THE AWARD OF THE DEGREE OF DOCTOR OF PHILOSOPHY OF
MAKERERE UNIVERSITY
January, 2006
DECLARATION
I, THEODORA SHUWU HYUHA, DO HERE DECLARE THAT THIS Thesis is my
own work and has not been submitted for a Degree Course in any other University.
Signature----------------------------------- Date-----------------------------------------
This thesis has been submitted with our approval as University Supervisors
Signed
........................................................................ ……………………………… Dr. Bernard Bashaasha Date
........................................................................ ……………………………… Dr. Ephraim Nkonya Date
........................................................................ ……………………………… Professor David Kraybill Date
ii
© 2006, Theodora S. Hyuha
All rights reserved. No part of this thesis may be reproduced, stored in any
retrieval system, or transmitted in any form by any means, electronic, mechanical,
photocopying, recording or otherwise without prior written permission of the author or
Makerere University.
iii
DEDICATION
To my late father Donozious Shuwu, my mother Mary Nambozo Shuwu and my daughter Hanifa Hyuha.
iv
ACKNOWLEDGEMENT
It is not possible to enumerate the names of all the people who helped me during the
period I was working on this thesis. Nevertheless it would be ungracious of me if I did
not thank some of them by name and others in general terms. The first people I wish to
express my gratitude to are those rice farmers who allowed me to ply into their private
lives by asking them endless questions regarding their rice enterprises. They were really
wonderful for they gave me their time freely. The second category of people to thank is
the district and village level officials. These officials also gave me unreserved
cooperation for they knew my success in the research would in some way or another lead
to the betterment of rice farmers’ livelihoods.
As a researcher, I designed the data collection instrument. However, during the
implementation stage, I was assisted by a number of student researchers drawn from
Makerere University. These were: Eria Hisali, John Kasembeli, Hon. Ahabwe Godfrey
(then lecturer at the department of Agricultural Economics and Agribusiness, Makerere
University) Ema Mugalazi, Madina Guloba, Brenda Piloya, Monica Atube and Agea
Jacob.
At Makerere University, I received a lot of encouragement from colleagues and friends
from the department of Agricultural Economics & Agribusiness, the faculty of
Agriculture at large and outside it. I am grateful to all of them. However, special mention
first goes to my Supervisors Dr Bernard Bashaasha, Dr Ephraim Nkonya (currently
working at International Food Policy Research Institute) and Professor David Kraybill a
v
Fulbright scholar currently working in the department. Second, Mr Jairus Mhehe
provided assistance in computer work. Mary Busingye and Joyce Oyella provided the
initial secretarial work. Thank you for being patient with me. Third, I am grateful to Mr
William Ekere, Mr Bernard Tayebwa, Professor Marion Okot and Mr Paul Kabasa for
their constant encouragement when the energy ran very low. Mr William Ekere has
amazing heart, he never at any time complained about my endless consultation about
computer gymnastics. Fourth, I am grateful to Dr Barnabas Kiiza for providing some
editorial work. Finally, I thank Professor Elly Sabiiti (former Dean of the faculty of
Agriculture) and the current Dean, Professor Matete Bekunda and their respective
executive for their constant encouragement and support.
The analysis of data and the write up of the first draft thesis was undertaken at the
University of Dar es Salaam, Economic Research Bureau. The Bureau gave me an office,
and unlimited access to internet and other facilities for serious writing. For this, my
gratitude goes particularly to Dr Godwin Mjema, the Director of the Bureau for his
generosity and for integrating me in their Bureau. While there, I presented a paper based
on my work in their regularly held seminars. I am grateful to the members of staff for the
constructive comments received from them. Out side the seminar room, I received useful
comments from Professor Robert Mabele, Dr Innocent Karamagi and Dr Micheal
Ndashau . The two secretaries of the Bureau namely, Mwanaisha Kassanga and Grace
Kiwia were great. External to the department, but within the University of Dar es Salaam,
Professor Letticia Rutasobya and Professor Fred Kaijage mentored me a great deal.
vi
The financial support was provided by African Economic Research Consortium (AERC),
International Food Policy Research Institute (IFPRI) and Faculty of Agriculture. I am
indeed grateful to these organizations.
My final thanks go to my husband Professor Mukwanason Hyuha and the family for
standing by me during the lengthy gestation period of this document.
In spite of all these numerous assistance from supervisors, colleagues, friends, family, the
errors and shortcomings remaining in the document are all mine.
vii
ACRONYMS
APC Agricultural Policy Committee
CRS The Chinese Rice Study Team
FAO Food and Agriculture Organization
GDP Gross Domestic Product
LDC Less Developed Countries
MAAIF Ministry of Agriculture Animal Industry and Fisheries
NAARI Namulonge Agricultural and Animal Production Research
Institute
NARO National Agricultural Research Organization
UBOS Uganda Bureau of Statistics
viii
ABSTRACT
Uganda is implementing the Plan for Modernization of Agriculture as one of the ways to
eradicate poverty in rural areas. Consequently, it becomes critical to access technical
information on strategic commodities, such as rice, which has become a major cash
earner. The main objective of this study was to determine profit efficiency in rice
production with a view to isolating factors leading to variation in farm-specific
inefficiencies.
The study relied on cross-sectional data collected in 2001 from three districts (Tororo,
Pallisa and Lira) of Eastern and Northern Uganda. Two models, namely a profit translog
stochastic frontier model and a firm-specific inefficiency model were used. The
parameters were estimated simultaneously, using FRONTIER 4.1 computer programme.
Results showed area under rice and capital had a positive influence on profit levels while
cost of family labor and “other inputs” had a negative effect. The analysis also showed
that all farmers were not operating on the profit frontier and scored a mean profit
efficiency of 66 percent with about 70 percent of the farmers scoring at least 61 percent.
The efficiency levels at the district level were 75, 70 and 65 percent, respectively for
Pallisa , Lira and Tororo, respectively.
Further analysis showed rice farmers were losing income due to allocative and technical
inefficiency. The established sources of inefficiency were: limited access to extension
services, low education, limited non-farm employment opportunities and lack of
experience in rice growing. Among these, lack of education, limited access to education
ix
and limited access to extension services were the major constraints to increasing profit
efficiency in rice enterprises. Based on elasticity estimates, the study also established
further that improving efficiency would require expansion of the area under cultivation,
which would have the greatest positive impact on profits.
x
TABLE OF CONTENTS
DECLARATION.................................................................................................................ii
DEDICATION....................................................................................................................iv
ACRONYMS...................................................................................................................viii
ABSTRACT.......................................................................................................................ix
LIST OF TABLES............................................................................................................xiv
LIST OF FIGURES..........................................................................................................xvi
CHAPTER I BACKGROUND........................................................................................1
1.2.......... Problem Statement...............................................................................................2
1.3.......... The Objectives of the Study................................................................................3
1.4.......... Hypotheses...........................................................................................................4
1.5.......... Organization of the Study....................................................................................4
CHAPTER II LITERATURE REVIEW AND THEORETICAL FRAMEWORK.. .5
2.1..........Meaning of Efficiency..........................................................................................5
2.2..........Theoretical Basis for Measurement of Efficiency................................................8
2.2.1.......Technical, Allocative and Economic Efficiency..................................................8
2.2.2.......Profit Function....................................................................................................10
2.3..........Profit Inefficiency Model...................................................................................13
2.4..........Technical Efficiency: Empirical Studies............................................................15
2.5..........Profit Function Analysis: Empirical Studies......................................................23
CHAPTER III METHODOLOGY................................................................................28
3.0..........Introduction.........................................................................................................28
3.1..........Approaches to Measuring Efficiency.................................................................28
3.2..........Deterministic Versus Stochastic Frontier Models..............................................29
xi
3.3..........Theoretical Profit Function and Stochastic Frontier Model.............................31
3.4 .........Empirical Models................................................................................................33
3.4.1.......Translog Stochastic Frontier Profit Function Model..........................................34
3.4. 2......Definition of Variables and Estimation of Profit Frontier Function...................36
3.4.3.......Variables Included in the Inefficiency Model....................................................40
3.5..........Study Area, Data and Sources............................................................................44
3.5.1.......Description of the Study Area............................................................................44
3.5.2.......The Data..............................................................................................................46
3.5.3.......Data Reliability and Validity..............................................................................48
3.6..........Data Analysis/Model Implementation................................................................54
CHAPTER IV RESULTS AND DISCUSSION............................................................56
4.0..........Introduction.........................................................................................................56
4.1..........Socio Demographic and Socio Economic Characteristics..................................56
4.2..........Testing for the Appropriateness of C-D Model..................................................60
4.3..........Estimation of Frontier Profit Function: Translog Model....................................65
4.4..........Profit Efficiency Score Estimates: Translog Model...........................................71
4.5..........Determinants of Firm-Specific Profit Inefficiency in Rice-Translog Model.....74
4.6.......... Key Constraints to Profit Efficiency in Rice Production...................................77
4.6 .........Summary.............................................................................................................82
CHAPTER V SUMMARY, CONCLUSIONS AND POLICY
RECOMMENDATIONS.................................................................................84
5.0 .........Introduction.........................................................................................................84
5.1..........Summary.............................................................................................................87
5.2.......... Conclusions and Policy Recommendations.......................................................90
5.3.......... Recommendations for Further Research...........................................................92
xii
REFERENCES..................................................................................................................93
APPENDIX A..................................................................................................................100
APPENDIX B..................................................................................................................119
APPENDIC C: MAP SHOWING STUDY DISTRICTS................................................130
xiii
LIST OF TABLES
Table 3.1: Variables Included in the Frontier Profit Function Models and their
Descriptions..............................................................................................38
Table 3. 2: Variables Included in the Inefficiency Model and Descriptions.........40
Table 3. 3: Skewness and Normality Variables (Unstandardized)- Translog
Model........................................................................................................51
Table 3. 4: Skewness and Normality Variables (Standardized)- Translog Model52
Table 3.5 Effect Magnitude Measures for the MLE result Estimates.................53
Table 3. 6: Tests of Significance using Two-Sample Kolmogorov-Smirnov Test. 54
Table 4.1a: Selected Socio-economic Characteristics of Farmers in the study area
...................................................................................................................58
Table 4.1b: Other Household Characteristics in the Study Area............................60
Table 4.2: Hypotheses Testing for the Models and its Inefficiency Effects..........64
Table 4.3a: Frontier Profit Function among Rice Producers in selected Districts66
Table 4.3b: Frontier Profit Function among Rice Producers in Tororo District. .68
Table 4.3c: Frontier Profit Function among Rice Producers in Pallisa District. . .69
Table 4.3d: Frontier Profit Function among Rice producers in Lira District.......70
Table 4.4: Frequency Distribution of Farm- Specific Profit Efficiency Index in
Studied Areas-Translog Model...............................................................71
Table 4.5 Comparison of mean Profit loss per hectare as a result of Profit
Efficiency by Districts..............................................................................73
Table 4.6 Tests of Significance of Mean Profit loss...............................................73
Table 4.7 Estimated Profit Elasticities in the studied Area..................................74
xiv
Table 4.8: Determinants of Farm-Specific Inefficiency in Rice Production in the
Sampled Districts.....................................................................................75
Table 4.9a Profit Loss in Rice Production in Tororo District by Key Constraints
...................................................................................................................79
Table 4.9b Profit Loss in Rice Production in Pallisa District by Key Constraints
...................................................................................................................80
Table 4.9c Profit Loss in Rice Production in Lira District by Key constraints....81
xv
LIST OF FIGURES
Figure 1: Stochastic Production Frontier....................................................................9
Figure 2: Frontier MLE and OLS Stochastic Profit Function.................................13
xvi
CHAPTER I
INTRODUCTION
1.1 Background
Agriculture plays an important role in Uganda’s economy. About 74.8% of the people in
Uganda not only live in the rural setting, but also depend on agriculture for their
livelihood. Of these 68.1% depend on subsistence agriculture (Uganda Bureau of
Statistics UBOS, 2005). In 2003, the agricultural sector contributed 40% of Gross
Domestic Product (GDP), (UBOS, 2004).
Rice is one of the emerging crops grown currently in Uganda. It plays an important role
both as a food and a cash crop in the country (Sabiiti, 1995; Ochollah et al., 1997). In
1997 it ranked first in terms of returns per labor day among major crops grown in the
country (Agricultural Policy Committee APC, 1997) and in 2005, a study by Jagwe et al.,
(2005) confirmed this for Kabarole distribution. The crop ranked fourth among the cereal
crops, occupying a total of 80 thousand hectares of land with an estimated output of 120,
000 tonnes (UBOS, 2004). It is becoming a staple food countrywide, especially in urban
areas (World Bank, 1993). Available figures show that Uganda consumed an average of
7,877 tons per annum over the four-year period of 1994-1997, and imported rice worth
184.5 million Uganda Shillings (US $ 174,386 thousand) for the same period. In 2003,
the country’s rice import requirements were estimated at 50 thousand tons (FAO, 2004).
Uganda is therefore a net importer of the commodity and will continue to do so in the
near future unless there is an improvement in domestic production. This is feasible as the
country has 70,000 hectares of land with ideal agronomic conditions for rice production
(CRS, 1982). However, the crop ranks low in terms of research among the cereal crops
within the National Agricultural Research Organization (NARO), an organization
1
charged with agricultural research in the country. It is only recently (1998) that the crop
has attracted the attention of agricultural research (personal communication with the
cereal Program Leader at Namulonge Agricultural and Animal Production Research
Institute (NAARI). Even then the emphasis is on upland rice and looking at agronomic
factors. Limited knowledge exists, particularly on socio-economics. The present study
thus makes a contribution to the empirical research in this field.
It should also be noted that, the current policy thrust with respect to agriculture in Uganda
is modernization of the sector (Ministry of Agriculture Animal Industry and Fisheries
MAAIF, 2000). This calls for increased research, on how best to increase productivity
and inform policy. It is hoped that the transformation of the sector can make a significant
contribution to poverty reduction efforts. The case of rice profit efficiency therefore
becomes interesting. However, the crop has faced a declining trend in yield in the last
five years (2000-2004). This trend needs to be reversed and hence the importance of this
study.
1.2 Problem Statement
Rice is largely grown as a cash crop in Eastern and Northern Uganda. Production of the
crop is therefore motivated by the economic objective of earning a positive economic
return. Meeting this objective requires efficient utilization of scarce resources. However,
there could be intervening variables which may hinder agents to realize this objective.
Thus, there is a need to examine profit efficiency in rice production in Eastern and
Northern Uganda and to identify factors that influence efficiency in this sector.
An approach that can be used to solve the problem of efficient utilization of scarce
resources focuses on two questions: first, whether farmers are economically (technically
2
and allocatively) efficient in rice production and second, what factors determine their
level of efficiency? Answers to these two questions provide a clue on how we can assist
farmers to be efficient in utilizing their resources employed in rice production.
To date, there is only one known study that has addressed efficiency and management
practices of Ugandan rice farmers (Ssenteza, 1993). Ssenteza (1993) estimated elasticities
using a Cobb-Douglas (C-D) production function of Kibimba rice scheme. Other related
studies include Yilma (1996) and Appleton and Balihuta (1996). Yilma (1996) estimated
productive efficiency of coffee and bananas in Masaka district while Appleton and
Balihuta (1996) focused on the impact of education on agricultural productivity in
Uganda. Thus there is a need to examine profit efficiency among rice producers in the
country with the view to providing answers to the aforementioned questions.
1.3 The Objectives of the Study
The main objective of this study is to examine the profit efficiency of rice production at
farm level in Eastern and Northern regions of Uganda.
The specific objectives of this study include the following:-
1) To characterize rice production system in Eastern and Northern Uganda.
2) To estimate the rice frontier profit function for Eastern and Northern Uganda and
determine factors influencing profit.
3) To determine farm specific factors that influence the observed variability of profit
efficiency levels among rice producers.
3
1.4 Hypotheses
In view of the problem and objectives, the following hypotheses are tested:
1) Rice farmers in Eastern and Northern Uganda are not operating on efficient
profit frontier.
2) There is no variability in the level of profit inefficiency among rice farmers in
Eastern and Northern Uganda.
3) Factors such as non-farm employment, education, access to extension
services and credit, experience, employment and degree of specialization in
rice production influence the observed level of profit inefficiency among rice
farmers in Eastern and Northern Uganda.
1.5 Organization of the Study
Chapter two begins with a discussion of the concept of economic efficiency. The rest of
the chapter covers issues concerning model development, and factors associated with
measurement of economic inefficiency. The chapter concludes with a review of empirical
studies concerned with measuring allocative and technical efficiency.
Chapter three provides a detailed discussion of the methodology adopted, conceptual
model, empirical model used in the study, and describes data sources. Both descriptive
and econometric results are discussed in chapter 4 while summary and conclusions are
presented in chapter 5.
4
CHAPTER II
LITERATURE REVIEW AND THEORETICAL FRAMEWORK
2.1 Meaning of Efficiency
The analysis of efficiency dates back to Knight (1933), Debrew (1951) and Koopmans
(1951). Koopmans (1951) provided a definition of technical efficiency while Debrew
(1951) introduced its first measure of the ‘coefficient or resource utilization’. Following
on Debrew in a seminal paper Farrell (1957), provided a definition of frontier production
functions, which embodied the idea of maximality. Farrell (1957) distinguished three
types of efficiency: 1) technical efficiency and 2) price or allocative efficiency and 3)
economic efficiency which is the combination of the first two.
Technical efficiency is an engineering concept referring to the input-output relationship.
A firm is said to be efficient if it is operating on the production frontier (Ali and Byerlee,
1991). On the other hand, a firm is said to be technically inefficient when it fails to
achieve the maximum output from the given inputs, or fails to operate on the production
frontier. Mbowa (1996) in his study on the sugarcane industry in South Africa defined an
efficient farm as that which utilizes fewer resources than other farms to generate a given
quantity of output. Yilma (1996), while studying efficiency among the smallholder coffee
producers in Uganda, defined an efficient farm as that which produces more output from
the same measurable inputs than that one which produces less. Fan (1999) referred to
technical inefficiency as a state in which actual or observed output from a given input
mix is less than the maximum possible.
5
Price or allocative efficiency has to do with the profit maximizing principle. Under
competitive conditions, a firm is said to be allocatively efficient if it equates the marginal
returns of factor inputs to the market price of output (Fan, 1999). Akinwumi and Djato
(1996) in their study of relative efficiency of women farm managers in Cote d’Ivoire
define allocative efficiency as the extent to which farmers make efficient decisions by
using inputs up to the level at which their marginal contribution to production value is
equal to factor costs. Failure to equate revenue product of some or all factors to their
marginal cost is at the very core of economic theory (Timmer, 1971). Similarly, Ali and
Byerlee (1991) agree with this definition in their review of economic efficiency of small
farmers in a changing world. They contend that allocative inefficiency is failure to meet
the marginal conditions for profit maximization. Thus allocative inefficiency is failure of
a farmer to equate marginal returns of factor inputs to its price.
Economic efficiency is distinct from the other two even though it is the product of
technical and allocative efficiency (Farrell, 1957). A firm that is economically efficient
should by definition be both technically and allocatively efficient. However, this is not
always the case as Akinwumi and Djato (1997) pointed out. It is possible for a firm to
have either technical or allocative efficiency without having economic efficiency. The
reason may be that the farmer, in this case, is unable to make efficient decisions as far as
the use of inputs is concerned. In some cases, a farmer might fail to equate marginal input
cost to marginal value of product. If technical and allocative efficiency occur together
they are both a necessary and a sufficient condition for economic efficiency. This
assumes that the farmer has made right decision to minimize costs and maximize profits
implying operating on the profit frontier. However, one needs to recognize that in least
developed countries (LDC’s) there are inherent market failures due to a number of
6
reasons such as unwarranted government interventions, lack of information on the
markets and poor infrastructure. Notwithstanding this phenomenon, this study adopts a
definition of efficiency, which encompasses technical and allocative efficiency, in
essence economic efficiency.
Apart from these definitions, literature on efficiency distinguishes many other forms of
efficiency and these are productive, scale (economies of size) and economies of scope
and x-efficiency. Production is said to be efficient if it is not possible to produce more of
one good without taking resources away from production of another good (Binger and
Hoffman, 1998). From the discussion by Wang et al., (1996b) production efficiency is
equivalent to economic efficiency because it combines two components, that is, technical
and allocative efficiency. Scale efficiency can also arise from spreading the cost of
production, particularly fixed costs over a large output. Taking an example of an
assembly line, it would not be cost effective if the firm opts to produce a few cars a year
when it is capable of producing a large number of cars to achieve low per unit cost. The
assembly reaps economies of scale when it experiences substantial cost savings at
relatively high output (Binger and Hoffman, 1998). But the firm can experience
diseconomies of scale due to coordination problems. According to Sadoulet and Alain de
Janvry (1995) the presence of economies of scale in agriculture is not conclusive.
Economies of scope exist when a firm decides to put two separate enterprises under one
management. The enterprises share the same factors of production such as labour and in
the process cut down on costs. In the process of sharing the factors, the management
saves on costs and as such it is able to reap economies of scope. X-efficiency is realized
through motivating staff who in turn work hard to produce maximum output.
7
2.2 Theoretical Basis for Measurement of Efficiency
2.2.1 Technical, Allocative and Economic Efficiency
Measurement of economic efficiency requires an understanding of the decision making
behaviour of the producer. A rational producer, producing a single output from a number
of inputs, x = x1……xn, that are purchased at given input prices, w = w1…..wn and
operating on a production frontier will be deemed to be efficient. But if the producer is
using a combination of inputs in such a way that it fails to maximize output or can use
less inputs to attain the same output, then the producer is not economically efficient. A
given combination of input and output is therefore economically efficient if it is both
technically and allocativelly efficient; that is, when the related input ratio is on both the
isoquant and the expansion path. These contentions are best illustrated in the figure 1.
In figure 1, AB is an isoquant, representing technically efficient combinations of inputs,
x1 and x2, used in producing output Q. AB is also known as the ‘best practice’1production
frontier. DD' is an iso-cost line, which shows all combinations of inputs x1 and x2 such
that input costs sum to the same total cost of production. However, any firm intending to
maximize profits has to produce at Q', which is a point of tangency and representing the
least cost combination of x1 and x2 in production of Q. At point Q' the producer is
economically efficient.
1 Coelli (1995) indicates that the production function of the fully efficient firm ‘best practice’ is not known in practice, and thus it must be estimated from the sample of the industry concerned.
8
Figure 1: Stochastic Production Frontier
Turning to measurement of technical, allocative and economic efficiency, the same figure
1 is employed. Suppose a farmer is producing its output depicted by isoquant AB with
input combination level of (X1and X2) in figure1. At this point (P) of input combination
the production is not technically efficient because the level of inputs needed to produce
the same quantity is Q on isoquant AB. In other words, the farmer can produce at any
point on AB with fewer inputs (X1 and X2) in this case at Q in an input-input space. The
degree of technical efficiency of such a farm is measured as OQ/OP. OQ/OP is the
proportional reduction of all inputs that could theoretically be achieved without any
reduction in output.
In figure 1, DD' represent input price ratio or iso-cost line, which gives the minimum
expenditure for which a firm intending to maximize profit should adopt. The same farm
using (X1 and X2) to produce output P would be allocatively inefficient in relation to R.
Its level of allocative efficiency is represented by OR/OQ, since the distance RQ
x 2/y
R >
Q
P
Q'
D'
D
x1/y
B
A
O
9
represents the reduction in production costs if the farmer using the combination of input
(X1 and X2) was to produce at any point on D D', particularly R instead of P.
The overall (economic) efficiency is measured as the product of OQ/OP and OR/OQ,
which is OR/OP. This follows from interpretation of distance RP as the reduction in costs
if a technically and allocatively inefficient producer at P were to become efficient (both
technically and allocatively) at Q'. These forms reflect alternative behavioral objectives
(i.e. profit maximization or cost minimization) and can account for multiple outputs
(Coelli, 1995).
2.2.2 Profit Function
A profit function is an extension and formalization of the production decisions taken by a
farmer. According to production theory, a farmer is assumed to choose a combination of
variable inputs and outputs that maximize profit subject to technology constraint
(Sadoulet and De Janvry, 1995). The underlying production function can be generalized
as h (q, x, z) = 0 where q is a vector of output, x is a vector of variable inputs, z is a
vector of fixed inputs and h is a technology. Assuming the technology to be
homogeneous across farms, restricted profit function is specified as follows:
Max p.q-wx,……………., s.t. h(q,x,z) = 0 1
Where: p is a vector of prices of outputs and
w is a vector of prices of variable inputs
10
Considering a set of inputs and outputs the profit maximizing input demand and output
supply functions are generally respectively expressed as:
X = x (p, w, z) 2
Q = q (p, w, z) 3
Substituting equation 2 and 3 into1 gives a profit function which is the maximum profit
that the farmer can obtain given prices of p and w, availability of fixed factors z and
production technology h(.). The profit function can be written as
π = p'q( p,w,z) - w'x(p,w,z) 4
This study uses the normalized profit function outlined in equation 5 given the fact that
the study is dealing with a single output, that is, rice (Sadoulet and De Janvry, 1995).
Hence for rice, we have:
π i = (Pij, Zik). exp (℮i ) 5
This makes profit non-linear in its error term. However, the profit function can be
loglinearized to obtain the form : ln i = lnf(.) + ei.
where:
πi = normalized profit on firm i defined as gross revenue minus variable cost
divided by the output price.
Pij = prices of variable input j on firm i divided by the output price.
Zik = level of fixed input on firm i where k are a number of fixed inputs.
i = 1,………………………….., n number of farms in the sample.
11
℮ i = error term assumed to behave in a manner consistent with the frontier
concept (Ali and Flinn, 1989).
Figure 2 shows the stochastic profit frontier function adopted from Ali and Flinn, (1989).
The stochastic profit frontier function is an extension of incorporating farm level prices
and input use in the frontier production function. The incorporation of the farm specific
level prices leads to the profit function approach formulation (Ali and Flinn, 1989; Wang
et al., 1996a). A production approach to measure efficiency may not be appropriate when
farmers face different prices and have different factor endowment (Ali and Flinn, 1989).
Hence the uses of stochastic profit function to estimate farm specific efficiency directly
(Ali and Flinn, 1989; Ali et al., 1994; Wang et al., 1996a). The profit function approach
combines the concepts of technical, allocative and scale inefficiency in the profit
relationships and any errors in the production decision translate into lower profits or
revenue for the producer (Rahman, 2003). Profit efficiency is defined as the ability of a
farm to achieve highest possible profit given the prices and levels of fixed factors of that
farm and profit inefficiency in this context is defined as the loss of profit from not
operating on the frontier (Ali and Flinn, 1989).
12
E O
Figure 2: Frontier MLE and OLS Stochastic Profit Function
Source: Ali and Flinn (1989)
In the context of frontier literature, DD in figure 2 represents profit frontier of farms in
the industry (the best practice firm in the industry with the given technology). EE is the
average response function (profit function) that does not take into account the farm
specific inefficiencies. All farms that fall below DD are not attaining optimal profit given
the prevailing input and output prices in the product and the input markets. They are
producing at allocativelly inefficient point F in relation to M in Figure 2. Profit
inefficiency is defined as profit loss of not operating on the frontier. In Figure 2, a firm
operating at F, is not efficient and its profit inefficiency is measured as FP/MP (Ali and
Flinn, 1989; Sadoulet and Janvry, 1995).
2.3 Profit Inefficiency Model
The issue of whether a farmer in a developing country is responsive to economic
incentive is now a mute point. The attention has shifted to how the whole system works
M
Normalized input price given fixed resources Pί/Zj
F
D
D
M
E
.·
$ Normalized Profit
P
·
E
13
(Ali and Byerlee, 1991). From an engineering point of view, a system is said to be
efficient if maximum output is generated from the given input keeping other factors
constant. If this ideal position does not obtain, it is said to be inefficient and the sources
of inefficiency could either be internal or external.
In agriculture, a farmer has to pay attention to relative prices of the inputs such that the
production is undertaken at the point where the isoquant is tangent to isocost line (Figure
1). If that is not done, economic efficiency is not achieved. The farmer may be able to
achieve technical efficiency but not allocative efficiency. This inefficiency could arise
from a number of sources, which include access to appropriate information in a timely
manner or lack of skills to take advantage of modern agricultural inputs. Basically, what
is being referred to here is the managerial ability of the farmer. The farmer should be able
to make decisions that lead to optimal utilization of resources and this requires accurate
information on availability of the new varieties, the inputs, and access to markets.
Besides, the farmer’s inability to make optimal decisions may be due to external factors,
which lie outside his/her prevue. These include untimely input supply, bad weather, non-
conducive policies and other random shocks such as wars, floods, pests and diseases,
droughts, and statistical errors. Inefficiency could also arise from the introduction of new
varieties without adequate provision of back-up packages to the farmers. In this learning
stage, a farmer could appear inefficient while he/she is not, due to the fact that he/she is
unfamiliar with the new variety. One has to recognize that it takes time to learn new
agronomic practices. During this learning stage, production functions among the farmers
would differ. Therefore, it is unrealistic to attribute all inefficiency to farmer’s own
inability to make rational decisions.
14
2.4. Technical Efficiency: Empirical Studies
This section presents a review of some of the technical efficiency studies. Lingard et al.,
(1983) applying a two-component model to panel data estimated a bias free agricultural
production function for the Philippine rice farmers in Luzon district. The study showed
that area was dominant in earlier years when the technology was introduced, while other
variables (such as irrigation, fertilizers and chemicals) became significant overtime,
reflecting full adoption of the technology.
The farm-specific efficiency was established through the 32 farm intercept terms on a
series of variables for the year, 1979. The results showed that the variables most highly
associated with farm-specific technical efficiency were soil type, credit access, education
and land tenure differences. However, the authors did not carry out a second stage
analysis of establishing factors affecting technical efficiency. Nevertheless, they
concluded that the managerial efficiency is an important factor in rice production in the
Philippines.
Belbase and Grabowski (1985) used corrected ordinary least squares (COLS) technique
to measure technical efficiency of farmers in Nuwakot District in Nepal. The
appropriately adjusted (removing the outliers) results showed that the Nepalese farmers
were operating close to the technical frontier. The factors contributing positively to
technical efficiency were: nutrition levels, family incomes and education. The structure
(farm size) of the farms was taken as given, yet as noted by Mbowa (1996), the variable
15
bears a significant influence on technical efficiency. Further, the Belbase and
Grabawoskis’ study did not deal with allocative inefficiency.
Taylor and Shonkwiler (1986) used both deterministic and stochastic frontier production
function to study the impact of agricultural credit programs on farmers in South eastern
Brazil. They used both models (deterministic and stochastic) to test the effectiveness of
the programme. The results showed that both groups (participants and non participants in
the programs) consistently had higher technical efficiency from stochastic than
deterministic frontier specifications. Yet in applying both specifications (deterministic
and stochastic) to analyse the effect of the credit programme to both participants and non-
participants, the results showed that the participants had higher technical efficiency than
the non-participants in deterministic specification. The two specifications, therefore,
yielded conflicting inferences regarding the effectiveness of the programs. In their
conclusion the authors noted that “such results place considerable importance on the
subjective beliefs of the researcher. Any definitive inference must, in the end, rest in the
gray area of determining which specification is the most realistic on both theoretical and
empirical grounds”; Taylor and Shonkwiler (1986).
A deterministic model attributes any deviation from the frontier as resulting solely from
inefficiency measured by μ. The major weakness with this model is that any
measurement error and any other source of variations in the dependent variable is
embedded in μ and can’t be separated. As a result, outliers may have profound effects on
the estimates and also, any shortcomings in the specification of the model could translate
into inefficiency estimates.
16
A stochastic model on the other hand, takes into account random factors, which are
outside the control of the farmer. The model addresses the noise problem characterizing
deterministic frontier. In other words, the model enables the researcher to provide more
explanation of the inefficiency observed than before. This was not possible before
because of the violation of certain maximum likelihood regularity conditions. The
coefficients estimated this way are expected to be more efficient parameters and its
popularity by researchers may be due to this held view (Thiam et al., 2001). However, the
model has its own shortcomings. It lacks apriori justification for the selection of a
particular distributional form for the one sided inefficiency term μ. In this study a
stochastic approach is adopted due to the reasons given earlier: provision of better
explanation on observed inefficiency at farmer level and getting more efficient parameter
estimates.
Unlike the previous studies reviewed, Kalirajan and Shand (1988) estimated technical
efficiency for multiple crops (rice-corn- rice)2 and multiple outputs using stochastic
translog production frontier for a sample of farmers operating in rain-fed areas of India.
The results showed that levels of crop-specific and farm-specific efficiency varied widely
among small farmers, but on the whole only 24% of the sample was found to be
technically efficient in growing all the crops. The causes of variation in technical
efficiency at farm level were found to differ across crops. In the case of rice, farming
experience and extension officials’ visits were found to be important whereas financial
availability was the most crucial to maize production. The authors concluded that a mere
2 Rice-corn-rice implies crop rotation of rice in the first season followed by corn in the next season and rice in the third season.
17
choice of high yielding technology is not sufficient to increase the production of rice,
what is important is the proper use or application of the technology.
Acknowledging the fact that measurement of efficiency is sensitive to methodology used,
the data, period, and sample, Dawson and Lingard (1991) employed two different
approaches to estimate technical efficiency of rice farms in The Philippines (Luzon
Province) namely, covariance analysis (CA) and stochastic frontier approaches. The CA
was used to pull together the cross-sectional and panel data. The CA produced biased
results, confirming observation made by Timmer (1971). Further, the estimation using
cross-sectional data set produced a wide range of coefficients while those of panel data
had better results. The range of technical efficiency ratings was narrower, with 14 farms
being over 90% or more efficient. The major strength of this study was that it succeeded
in showing that efficiency estimates are sensitive to methodology, type of data, and
sample size. More crucial to the current study, is the fact that Dawson and Lingard (1991)
pointed out that there was a need to go beyond identification and develop methodologies
that explain sources of differences in farm efficiency.
Besides stochastic approaches, the non-stochastic3 frontier approach is one of the
methods that can be employed to estimate relative efficiency. Ali and Byerlee (1991)
revealed that the studies which used non-stochastic approaches, concentrated on non-
conventional inputs, such as education. Most of the studies reviewed showed that
education had positive and significant effect on productivity. The variable contributed up
to 9.5% increase in productivity in a modernizing (countries that have undergone green
33 Non-stochatic frontier approaches attribute all deviation from the frontier as due to to technical inefficiency.
18
revolution) agriculture. However, the unsolved puzzle is about which level of education
matters in farm management. Some studies have indicated that basic formal education of
up to 4 years is essential, particularly the farm manager, irrespective of gender (Appleton
and Balihuta, 1996; Weier, 1999).
Building on other studies, and still in quest to find a better and efficient approach to
measure efficiency, other researchers such as Phillips (1994) and Thiam et al., (2001)
reviewed studies on technical efficiency using a method called meta-analysis. The
method uses empirical estimates of some indicator from several studies; the average
technical efficiency in this case serves as the dependent variable, and attempts to explain
the variation of the estimates based on differences across studies as explanatory variables
in a regression model. Thiam et al. (2001) was the first to use this approach to analyze
technical efficiency.
The issue that empirical measures of efficiency depend on the choice of the model
adopted still remains controversial. Thiam et al., (2001) conclude, that “despite this array
of applied work, the extent to which empirical measures of efficiency are sensitive to the
choice of methodology remains a matter of controversy”. But this is not limited to
efficiency studies. Many other results are sensitive to methodology; data and time the
data were taken. Even though the study by Thiam et al,.(2001) covered 32 frontier
studies, using farm level data from 15 different developing countries, none of the method
was superior to the other in terms of robustness. Thiam et al,.(2001) concluded that the
groundwork remained a challenge to researchers.
19
Indeed, earlier on, Kalirajan and Obwona (1994) investigated the appropriateness of the
use of stochastic frontier methodology to estimate efficient utilization of the inputs given
the technology. The authors argued that by nature of its generic assumptions, that is, the
potential frontier being a neutral shift frontier from the realized production function,
input-specific technical efficiency measures could not be obtained without contradictions.
They further argued that even with the same identical levels of inputs, outputs would
differ due to differences in the methods of application of inputs by the farmer. Thus it
would be necessary to use a different model, which reflects the method of application of
inputs by individual farmers.
Kalirajan and Obwona (1994) therefore went ahead and developed a Cobb-Douglas type
of production function to address these concerns and computed actual response
coefficients for individual observations. The result results obtained showed that there
were variations in the farm-specific and input-specific actual response coefficients across
sample farms. The authors therefore rejected the assumptions of the conventional
stochastic frontier production function approach and used a non-stochastic frontier Cobb-
Douglas (C-D) type of modeling of the production behavior of farmers. The authors
concluded that the developed model was appealing because it made it easy to draw policy
recommendations for the estimated results indicate the type of input being over or
underutilized. Secondly, it was possible to set targets for different inputs to produce a
given level of output. A latter study by Sharma et al., (1999) on Hawaiian swine farmers,
applying the parametric stochastic and nonparametric approach Data Envelope Analysis
(DEA)4 method produced results that were also robust. The method differs from the
parametric method in that the researcher does not have to make arbitrary assumptions
4 A DEA is a non-parametric mathematical programming approach to frontier estimation.
20
about the functional form of the frontier and distributional form of the μ. Additionally,
DEA does not make assumptions about the efficiency of farms since it measures relative
efficiency of farms, given a set of inputs DEA also differs from Farrell’s single-input,
single output efficiency analysis to multi-input, multi-output efficiency analysis.
However, according to Coelli (1995) the method also suffers from the same weaknesses
as that of the deterministic model covered before.
Studies estimating technical efficiency in Africa are limited. A review of some of them
follows. Yilma (1996) used three different approaches to estimate smallholder efficiency
in coffee and bananas namely, deterministic parametric, stochastic frontier approaches
and DEA in Masaka district, Uganda. The deterministic parametric approach showed
differences in mean scores of efficiencies in coffee and generally food production. The
coefficients estimated under deterministic parametric frontier model showed lower
efficiency than the stochastic frontier model, agreeing with many earlier studies
(Kalirajan and Obwona, 1994 and Lingard et al., 1983). Nevertheless, irrespective of the
approach used, all farmers were found not to be producing on the frontier.
Mbowa (1996) used DEA to examine resource use farm efficiency on small and large-
scale farms in sugarcane production in Kwazulu-Natal. The study results showed that
small-scale farmers were technically inefficient than large-scale producers and concluded
that the size of farm operation affects level of efficiency attainable.
21
Seyoum et al., (1998) used a two step procedure 5proposed by Coelli (1996a)6 to estimate
separate stochastic frontier production functions for the two groups of maize farmers
(within and outside Sasakawa Global (SG)2000 project) in Ethiopia. Empirical results of
the study showed that technical efficiency levels for the participating group were higher
than that of the non-participants. Furthermore; the participating group also registered
higher mean frontier output than those outside the project. The inefficiency model
showed that there exists technical inefficiency in the production of maize. The
contributing factors were education, age, and extension contact. Education and extension
services had a negative influence on technical inefficiency for those participating in the
project. The authors therefore concluded that in order to promote agricultural productivity
the government could introduce projects such as SG2000 which appear to have had a
positive impact on technical efficiency.
Appleton and Balihuta (1996) studied the impact of education on agricultural
productivity. Using the national household survey data, they found that education of at
least 4 years of formal schooling of the farm manager appears to raise production by 7
percent. They also found that there were large effects of education on other farmers in the
neighborhood. However, the analysis was limited in scope since they focused on
agricultural production only. This study intends to focus on estimating profit function
which takes into consideration prices of outputs and inputs.
5 The procedure involves estimating frontier profit function first and then using residuals of this function to estimate the inefficiency effects
6 The version 4.1 estimates the variance terms of and where has the
value of 0 to 1.When it is close to 1 the observed variation of the parameter is attributed to the farmer.
22
Weier (1999) examined the benefits of schooling upon farmer productivity and efficiency
employing both average production function and a two-stage-stochastic frontier
production functions in rural Ethiopia. As in the case of Appleton and Balihuta (1996),
the authors used household budget data set. The analysis revealed that at household level
farmers in rural Ethiopia were not operating on the frontier. The results suggested that
education has a role to play in increasing agricultural production.
2.5 Profit Function Analysis: Empirical Studies
This section reviews some of the studies conducted in Asia and Africa using profit
analysis approach. The review begins with studies were conducted on African continent.
Saleem (1988) tested the Marshallian theory in Sudan to find out which system
(sharecropping or fixed rent) operating on irrigated cotton farms was efficient.
Marshallian theory on sharecropping states that farmers operating under fixed rent should
be more efficient than those under sharecropping (Saleem, 1988). According to this
theory, farmers who have to pay rent tend to equate the marginal value of product (MVP)
of a variable factor to market price of that factor whereas those on share cropping have no
incentive to do so. They may instead equate a fraction of MVP to its market price. This
may happen when the input is subsidized. This is not true in many developing countries,
where subsidies don’t exist.
Applying Lau and Yotopolous (L-Y) profit function model to the data, Saleem (1988)
found out that the two farmer groups both growing medium staple cotton, respectively in
Gezira (shared) and Rahad (fixed) schemes were equally technically and price efficient,
in other words economically efficient. The results therefore did not support Marshallian
theory on rent and suggested that both groups had identical profit functions. The author
23
was not able to estimate farm-specific differences in profit efficiency among these
farmers. In light of this, this study uses an identical profit function for the farmers in
Doho and Olweny rice schemes. Farmers in Doho either rent or own plot(s) whereas in
Olweny Scheme, farmers use plots without paying rent because it is a government owned
scheme.
The relationship between firm size and efficiency has major implications to policy
options for agricultural development in Africa. The previous studies carried out in Asia
gave conflicting results on which size is more efficient -large or small (Akinwumi and
Djato, 1996). But, in the case of Africa, the superiority (more efficient) of large-scale
farms was apparently artificial because (according to the authors), the large-scale farmers
had in the past been given preferential treatment over the small scale-farmers. For
instance, the latter group tended to have restricted access to certain markets for their
commodities and as such they could not demonstrate their efficiency in growing the crop
in question. Indeed, in their study of rice farms in Ivory Coast, Akinwumi and Djato
(1996) found no significant differences in economic efficiency between small and large
rice farmers in Cote d’Ivoire. But in general, they found absolute allocative inefficiency
within the rice sector.
Yotopoulos and Lau (1973) extended their 1971 study with the major purpose of isolating
the causes of observed differences in economic efficiency between large and small scale
farmers. Using a stochastic profit frontier approach, the authors reaffirmed their earlier
findings that small farms had relatively higher economic efficiency than large farms and
that both groups of farms succeeded in maximizing profits. Nevertheless, small farmers
were found to be more technically efficient than large scale farmers. But, the authors
24
were not able to provide an explanation for the observed differences in technical
efficiency (Yotopoulos and Lau, 1973).
Even though it is very instructive to have knowledge on farm efficiency levels, under
different production system, what is equally important, from the policy point of view, is
to pinpoint the causes of the observed efficiency levels. Ali and Flinn (1989) adopting the
theoretical model formulated by Yotopoulos and Lau (Y-L), and using techniques
proposed by Jondrow et al., (1982) to estimate farm-specific efficiency among the
Basmati rice producers in Pakistan Punjab, found that farmers exhibited a wide range of
profit inefficiency ranging from 87% less than maximum profit to 5% less than maximum
profit. The results also showed that the variance ratio parameter λ7 proposed by Battese
and Corra (1977) was statistically greater than zero, implying that the variation in actual
profit from maximum profit between farms arose from differences in farmers’ practice
rather than random variability.
The study also found that the major determinants for profit loss among the Basmati rice
producers were both socio-economic and institutional factors. The former accounted for
52% profit loss and, of these, education alone accounted for 31%. The latter accounted
for 25% of profit loss. However, factors associated with resource base were not
significant in explaining the profit loss and only explained 12% while institutional factors
explained 25%. Rahman (2002, 2003) estimated a stochastic profit function for
Bangladesh rice farmers. The results showed that there existed a high level of
inefficiency in rice farming because γ was close to one. The average profit efficiency
7 λ is the likelihood- ratio test statistic which is = -2{log [Likelihood (H0)]-Log [Likelihood (H1)]} and has approximately χ2
ν distribution with ν equal to the number of parameters assumed to be zero in the null hypothesis (Rahman, 2002). λ is bounded and lies between 0 and 1. When the null hypothesis is rejected, it implies that the inefficiency exist in the estimated model and are stochastic.
25
scores were 60%, which implied that the farmers could improve their profitability by as
much as 40%.8 The farmers also exhibited a lot of profit inefficiency. The farm-specific
factors responsible were poor access to input markets, unfavorable tenancy arrangements,
and off farm employment.
A slightly different but as yet unsettled proposition is whether female farmers are as
efficient as male farmers in agricultural operations. Quoting FAO (1985), Akinwumi and
Djato (1997) observed that the argument used to discriminate against female farmers in
projects is that they are not efficient. Yet, Moock (1976) showed that female managers in
Vihiga district in Kenya were as efficient as men. Nkonya et al., (2004) found Ugandan
women farmers to be more efficient. Other studies give mixed results. This is attributed
to reliance on the production function, which suffers from simultaneous bias (Akinwumi
and Djato, 1997). The authors used profit function approach for rice farmers in Cote
d’Ivoire to settle this debate empirically. They found that the relative degree of economic
efficiency of women rice farmers is similar to that of men rice farmers in Cote d’Ivoire.
The authors concluded that there was no economic rational for biasing rice development
strategies towards male farmers in Cote d’lvoire because when the two groups have equal
access to inputs; they would exhibit equal levels of economic efficiency.
A review of literature by Ali and Byerlee (1991) on economic efficiency of small farmers
in a changing world revealed a need for sharpening conceptual and methodological
problems to derive useful policies. On methodological level, the authors suggested
widening the specification of production function to include environmental factors such
as soil types and rainfall when measuring economic inefficiency. These factors, they
8 Wide variations in profit efficiency were observed, but were skewed to the right.
26
argued, are normally left out by economists, which lead to misspecification of the model.
Yet, including environmental factors helps to reduce the usually overestimated technical
inefficiency. On the conceptual level, the authors argued that the distinction drawn by
economists between allocative and technical inefficiency is not meaningful because it
may be dictated by aggregation of purchased inputs and level of application. Most of the
studies reviewed by the authors were from Asia, efforts are required to generate
information on Africa. As Akinwumi and Djato (1996) observed, “studies in Asia cannot
be used directly to inform an agrarian policy in Africa”.
27
CHAPTER III
METHODOLOGY
3.0 Introduction
This chapter elaborates on approaches to measure efficiency, discusses theoretical
advances to efficiency models explains, justifies and discusses the implementation of the
translog model adopted in this study. The chapter concludes by describing the study area,
data sources and discusses tests for data reliability and validity.
3.1 Approaches to Measuring Efficiency
Following Farrell’s (1957) work, there has been a proliferation of studies in the field of
measuring efficiencies in all fields. But in the field of agriculture, the modeling and
estimation of stochastic function, originally proposed by Aigneir et al., (1977) and
Meeusen and van den Broeck (1977), has proved to be invaluable. A critical narrative of
the frontier literature dealing with farm level efficiency in developing countries
conducted by Battese (1992), Bravo-Ureta and Penheiro (1993), Coelli (1995) and Thiam
et al., (2001), indicated that there were wide-ranging theoretical issues that had to be
dealt with in measuring efficiency in the context of frontiers and these included selection
of functional forms and relevant approaches (parametric as opposed to non-parametric).
Parametric and non parametric models differ in two ways. First, the two models differ on
assumptions of the distribution of the error term that represents inefficiency. Second, they
differ in the way the functional form is imposed on the data. Parametric methods impose
28
functional and distributional forms on the error term whereas the non-parametric methods
do not.
Nevertheless, parametric models suffer from the same criticism as the frontier
deterministic models, in a sense that they do not take into account the possible influence
of measurement errors and other noises in the data as do stochastic frontier models
(Thiam et al., 2001). The results can also be misleading because they do not allow for
random error as in stochastic parametric approaches. Besides, non-parametric methods
also lack statistical tests that would tell us about the confidence of the results. For this
reason, this study adopts the stochastic parametric model and profit function frontier for
rice farmers.
3.2 Deterministic Versus Stochastic Frontier Models
According to Taylor and Shonkwiler (1986), Afriat (1972) was the first to propose the
formulation and application of a deterministic production frontier model. The basic
structure of the model is:
Y = ƒ (х, ß) е-μ...............................................................................................................(6)
where ƒ (х, ß) denotes the frontier production function and μ is a one-sided non-negative
distribution term. This model imposes constraint of μ≥0, which implies output is less than
the potential or it is equal to the potential, within the given input and output prices.
According to Taylor and Shonkwiler (1986), the model is in full agreement with
production theory, but the main criticism against it is that all the observed variations are
accounted for by the management practices as pointed out in section 3.1.No account is
taken of statistical noise such as random errors, omitted variables and shocks.
29
Stochastic models begin with Aigner and Chu (1968) who proposed a composed error
term, and since their work much effort has been exerted to finding an appropriate model
to measure technical efficiency. The result was the development of a stochastic frontier
model (Aigner, et al., 1977, Meeusen and van den Broeck, 1977, Battese and Corra,
1977). The model addressed the weaknesses of the deterministic model by introducing ν
into the deterministic model to form a composed error term model (stochastic frontier).
The error term of the stochastic model is assumed to have two additive components: a
symmetric component accounting for pure random factors and a one-sided component
that captures the effects of inefficiency relative to stochastic frontier. The model is
specified as follows:
ƒ (х, ß) е ν-μ........................................................................................................................(7)
where ƒ ( х, ß), is as defined in (6) and ν-μ is error term, ν represents factors external to
the farmer and are assumed to be independently and identically distributed (iid) as
Ν(0,σν2); μ is half-normal distribution or exponential distribution. The model addresses
the weaknesses of the deterministic model. It is also possible to estimate standard errors
and test for hypotheses that the observed inefficiency is not due to farmer’s practices only
as suggested in deterministic model (Thiam et al., 2001). Jondrow et al., (1982) provided
an explicit formula to separate the two component error term for both half normal
distribution and exponential distribution cases. Though this was an improvement over the
deterministic model, it was still constrained by lack of a priori justification for the
selection of a particular distributional form for the one-sided inefficiency term μ (Thiam
et al., 2001).
30
3.3 Theoretical Profit Function and Stochastic Frontier Model
A profit function under mild ‘regularity conditions’ is a logical extension of the
production function (Sadoulet and Alain de Janvry, 1995). Regularity conditions require
that the function must be non-negative, monotonically increasing in output, convex and
homogeneous of degree zero in all prices. To estimate the profit function, in the
neoclassical theory, it is assumed that the farmer is operating on the frontier and the price
of inputs and outputs are known. But in reality some of the farmers operate below and
some above the frontier.
Furthermore, Junanker (1989) observed that farmers do not always operate in competitive
input and output markets in developing countries and this violates the neoclassical
assumptions. Since Junanker’s observation, there have been a number of developments to
respond to this criticism. First, the assumption of output and input competitive markets is
not needed in defining the firm’s profit function, especially in developing countries. What
is needed is the output and input prices to be exogenous to the farm but be competitively
determined (Sevilla-Siero, 1991). Secondly price variation can be handled by including
district dummies (Lau and Yotopolous, 1971; Akinwumi and Djato, 1996). Third, it is
currently possible to incorporate institutional and environmental factors referred to earlier
such as quality of soils and rainfall as shown by (Ali and Flinn, 1989; Coelli ,1995).
Fourth, profit function does not suffer from simultaneous equation bias problems as in
production function. Fifth, the function has been used before in African context (Saleem,
1988; Akinwumi and Djato , 1996 and 1997). Thus, a stochastic profit function approach
is deemed appropriate for this study. This study adopts the Ali and Flinn’s model
specified in equation 8:
π ј = ƒ (Pιј, Zκј, Dіј).exp e ј....................................................................................................(8)
31
Where
π ј = normalized profit of јth farm defined as gross revenue less variable cost,
divided by commodity prices from farm j.
Pιј = prices of the variable inputs on jth farm,
Zκј = kth fixed factors on jth farm and
Dіј = exogenous variables on jth farm,
e ј = an error term, and ј = 1,…….n, is the number of farms in the sample.
If equation 8 is estimated using the Ordinary Least Squares (OLS) procedures, an
average, instead of best practice frontier is shown by an envelope curve EE (figure 2)
given in chapter 2. To attain ‘best practice’ frontier, an appropriate error structure is
appended to equation 8. Following Kmenta (1986), the study by Ali and Flinn (1989)
proved that the same error term as that used in production function frontier analysis was
relevant to profit frontier. Thus the following error term specified in equation 9 was used:
e ј = νј- µ ј..............................................................................................................................................(9)
where νј and µј are random error terms and inefficiency effects of the farm ј, respectively.
When µј = 0, the firm lies on the frontier but if µ ј>0 the farm is profit inefficient and
incurring losses.
The inefficiency effects (µј) in equation (9) which are non-negative random variables are
assumed to be identically and independently distributed such that µј is defined by the
truncation (at zero) of the normal distribution with a mean of
and variance where are the variable representing socio-economic characteristics
of farm j to explain inefficiency and δ0 and δd are the unknown parameters to be
32
estimated. The profit efficiency of the farm in the context of stochastic frontier is given by:
ζj = E [ exp(-µ ј)| e ј] = E[exp(- ..............................................................(10)
where ζj is profit efficiency of farmer j and lies between 0 and 1 and is inversely related to
the level of profit inefficiency. E is the expectation operator. This is achieved by
obtaining the expressions for the conditional expectation µј upon observed value of ζj.
As pointed out by a number of researchers including Akinwumi and Djato (1996, 1997),
a profit function is much superior to production function because first it permits straight
forward derivation of own-price and cross-price elasticities and output supply and input
demand functions, second, the indirect elasticity estimates via profit function have a
distinct advantage of statistical consistency, third, it avoids problems of simultaneity bias
because input prices are exogenously determined. Akinwumi and Djato (1997) quoting
Quismbing(1994) confirm that “problems of endogeneity can be avoided by estimating
the profit or cost function instead of the production function”. Besides, the profit function
is extensively used in literature (Yotopoulos and Lau, 1973; Saleem, 1988; Akinwumi
and Djato, 1996 and 1997; Abdulai and Huffman, 2000).
3.4 Empirical Models
In this section, a discussion of the empirical models that are used in estimating the profit
function, the profit inefficiency model and the determinants of profit inefficiency are
presented.
33
3.4.1 Translog Stochastic Frontier Profit Function Model
A number of functional forms exist in literature for estimating the profit function which
includes the Cobb-Douglas (C-D) and flexible functional forms, such as normalized
quadratic, normalized translog and generalized Leontif. The C-D functional form is
popular and is frequently used to estimate farm efficiency despite its known weaknesses
(Saleem, 1988; Kalirajan and Obwona, 1994; Dawson and Lingard, 1991; Yilma, 1996;
Nsanzugwanko et al., 1996; Battesse and Safraz, 1998). The translog model has its own
weaknesses as well, but it has also been used widely (Ali and Flinn, 1989; Wang et al.,
1996b). The main drawbacks of the translog model are its susceptibility to
multicollinearity and potential problems of insufficient degrees of freedom due to the
presence of interaction terms. The interaction terms of the translog also don’t have
economic meaning (Abdulai and Huffman, 2000).
A solution to these problems would be to estimate both (C-D and Translog) and then use
the results of the values of the Loglikelihood at the set critical value to reject or accept
one model over the other. Battesse and Safraz (1998) tried both models and found that the
C-D production function model was an adequate representation of the data. This study
runs both the C-D and translog frontier profit function models. Both of these models have
been widely used in Asia and Africa (Ali and Flinn, 1989; Saleem, 1988; Abdulai and
Huffman, 2000 and Rahman, 2002, 2003) as earlier noted. Suppressing the subscript j of
the farm, the flexible translog profit equation (11) and the inefficiency equation (12)
estimated in this study are respectively presented as follows:9
9 The model is adopted from Rahman (2002, 2003) with some modifications.
34
.............................................................................................(11)
where:
.........................................................................................................(12)
for all
restricted normalized profit computed for farm defined as gross revenue less
variable costs divided by farm specific rice price
ln = natural log
= price of variable inputs normalized by price of output where (for i =1,
2, and 3) so that:
= the cost of hired labor normalized by price of rice ( )
= the cost of “other inputs” normalized by price of rice ( )
= Imputed cost of family labor normalized by the price of rice ( )
= the quantity of fixed input (
= 1, 2)
where :
= land under rice (hectares under rice) for each farm j
35
= capital used in farm j (sum of total cost of hoes and pangas)10.
μ = inefficiency effects
= truncated random variable
= constant in equation 12
= variables explaining inefficiency effects and are defined as follows:
= non-farm employment
= education
= extension services
= credit access
= experience
= degree of specialization
α0, αi , rik ø , β , , φ , δ0 and d, are the parameters to be estimated.
3.4. 2 Definition of Variables and Estimation of Profit Frontier Function
Table 3.1 shows a list of variables included in profit frontier function (model 11). The
variables were picked based on the literature earlier reviewed. Labor is included in the
model because it is one of the primary factors of production. It has been disaggregated
into cost of hired labor ( ) and imputed cost of family labor ( ) as done in a number of
profit efficiency studies (Ali and Flinn, 1989; Saleem 1988). However, some other
studies treat labor differently by aggregating all the labor and normalizing it with the
output prices (Lau and Yotopoulos, 1971; Abdulai and Huffman, 2000, Akinwumi, and 10 The items were assumed to be used up in one production year therefore no depreciation is necessary
36
Djato, 1996 and 1997; Sharma et al., 1999). Ali and Flinn, (1989) treat family labor as
fixed factor and hired labor as variable factor. Both cost of hired and imputed cost of
family labor is treated as variable cost in this study.
In addition, there is a controversy as to whether men and women should be assigned the
same weight when valuing labor. The basic argument is that a female’s hour of work is
not equivalent to a man’s hour. The practice has therefore been to value women’s hour
differently. In a number of cases, it has been put at 75% of men’s. Basing on the
prevailing average wage rate, Abdulai and Huffman (2000) treated females’ and
children’s labor as equivalent to half of the man’s. Moock (1976) in his study in Vihiga
district in Kenya and Akinwumi and Djato (1997) in their study on rice in Ivory Cost
gave the same weight to both men and women. Similarly, Ali and Flinn (1989) in their
study on rice in Pakistan assigned the same value to men and women. Since a consensus
is building up in favor of not discriminating between the two, this study treated labor of
men and women to be equivalent to 1 person unit; children’s labor was 50% of the adult
labor. Variable (fertilizer and insecticide) use in production enhance productivity
37
Table 3.1: Variables Included in the Frontier Profit Function Models and their Descriptions
Variable Descriptions Expected
sign
Normalized profit of the th farm defined as
gross revenue less variable cost divided by farm
specific price (dependent). Note the j is
suppressed.
Variables
Normalized cost of hired labor divided by price
of rice.-ve
Normalized cost of “other inputs” (fertilizer and
pesticides) divided by price of rice. -ve
Normalized imputed cost of family labor on the
farm x the prevailing wage rate divided by price
of rice.
-ve
Fixed factors
Land under rice in hectares on farm +ve
Cost of capital (hoes and pangas) used in farm -ve
Fertilizer used on the farm is a variable factor of production. Weir (1999) found fertilizer
to have a positive and significant impact on output. However, Rahman (2002) found a
weak relationship of fertilizer use and profit efficiency among the Bangladesh farmers.
Abdulai and Huffman (2000) registered negative sign for rice farmers in Northern Ghana.
38
In this study, preliminary analysis of the results showed that few people in Uganda used
fertilizer and pesticides in rice production. Therefore, “other inputs” was arrived at by
multiplying the quantity of each input by their respective prices and treated as ( )
(Table 3.1). It is hypothesized that the cost of inputs affects profit efficiency negatively.
Land ( ) is defined as net area covered by rice and was treated as fixed input in line with
(Lau and Yotopoulos, 1971). The authors argued that given the periodic nature of
agricultural technology, it was reasonable to treat land as a fixed factor in the short run
and hypothesized to effect profit efficient positively. Capital ( ) in this study was
derived as the sum total of the cost (using the prevailing prices) of hoes and pangas. It
was also assumed that these items would be used up in one season as Akinwumi and
Djato (1996 and 1997) assumed for the case of rice farmers in Cote d’Ivoire.
39
3.4.3 Variables Included in the Inefficiency Model
The variables included the Inefficiency model in equation 12 are presented in Table 3.2.
Table 3. 2: Variables Included in the Inefficiency Model and Descriptions.
List of Variables Descriptions Expected sign
μ Inefficiency effects
Intercept term
Non farm employment 1= have non-farm employment = 0 other wise
Education level of a respondent in years -ve
Extension service visits to farm 1= received extension visits 0=otherwise
-ve
Credit access by farmer 1=access 0 = otherwise -ve
Experience measured by years in rice production by farmer
-ve
Degree of specialization in rice (acreage in rice/total crop acreage) in farm
-ve
One of the variables included in the model is non-farm employment ( ). It was included
to capture access to extra income, which can then be used to buy, among other items,
agricultural inputs and thereby possibly reduce inefficiency. Rahman (2002) included the
variable to capture unemployment situation in Bangladesh. However, engaging in non-
farm employment may deprive the farm of valuable time to make timely decisions. In this
regard, the variable was expected to have a positive impact on inefficiency (Rahman
2002, 2003 and Abdulai and Huffman, 2000, Ali and Flinn, 1989). In this study it is
hypothesized to have an indeterminate influence on inefficiency.
40
Through education ( ), the quality of labor is improved and with it the propensity to
adopt new technologies. However, education has varying impacts depending on the
environments, and has been proposed to be more effective in a rapidly changing
technological or economic environment (Shultz, 1964 and 1975). Furthermore, the issue
of a threshold is very important in determining what level of education the country should
give to its people to raise productivity. Appleton and Balihuta (1996) in their study in
Masaka district in Uganda showed the education threshold to be 4 years. In the same
district, Yilma (1996) in his study on smallholder efficiency in coffee and food-crop
production found it to be 10 years. Earlier, Jamison and Moock (1984) in Nepal found it
to be 7 years.
The other education related question pertinent to this study is: whose education matters to
agricultural productivity? Many studies capture the education of the head of the
household, while others take it for all members of the household. In others, the
community education is taken. Appleton and Balihuta (1996) used education of the entire
household and found that total years of the farm workers were significant. Weir (1999)
found a positive impact of average years of education in the village placement of
production frontier. Appleton and Balihuta (1996) did not find community education to
be significant.
41
Education is hypothesized to affect inefficiency negatively, and it is captured for the
respondent11. Weier (1999) treated years of schooling of the household head separately
from years of schooling of other adults in the household. Education is perceived to
enhance allocative ability. According to Abdulai and Huffman (2000), this stems from
the fact that response to changes in economic conditions requires first, perceiving that
change has occurred, second collecting, retrieving, and analyzing useful information,
third, drawing valid conclusions from the available information, and fourth, acting
quickly and decisively.
Access to extension services ( ) is a conduit for the diffusion of new technology among
farmers. Thus it should reduce inefficiency levels among rice farmers through
improvement in managerial ability. Ali and Byerlee (1991) review of a number of studies
on economic efficiency reported negative influence of extension services on inefficiency.
Bravo-Ureta and Rieger (1991) reported a positive relationship between extension
services and economic efficiency for the dairy farms in New England, U.S.A. Similarly,
Seyoum et al., (1998) studying the impact of SG 2000 project on participating maize
producers in Eastern Ethiopia, also reported a negative influence on extension services.
Rahman (2002, 2003) reported negative results for the variable, implying improvement
among those rice farmers who had contact with extension officers in Bangladesh.
Therefore, access to extension services was hypothesized to have a negative effect on
profit inefficiency.
11 The debate on education concerns what type of education and whose education This debate is beyond the scope of this report The interested reader can consult (Weier, 1999)
42
Adoption of new methods to increase efficiency does not depend only on availability of
technologies; it also depends on whether the farmer has the cash to purchase the
recommended inputs. Therefore, credit ( ) should play a crucial role in inefficiency
improvement and should have a negative relationship with profit inefficiency. Lingard et
al., (1983) found a negative relationship between credit access and inefficiency level in
Central Luzzon, Phillipines. Ali and Flinn (1989) reported similar results for Basmati rice
farmers in Pakistani. Results of a study by Abdulai and Huffman (2000) results on rice
farmers in Northern Ghana also found credit access to be negatively related to profit
inefficiency. Thus in this study credit was hypothesized to be negatively related to profit
inefficiency.
Experience ( ) in rice production should have a direct relationship with profit
inefficiency. As one gets proficient in the methods of production, optimal allocation of
resources at his/her disposal should be achieved. Thus the more experienced one is the
higher the profit and the lower the profit inefficiency. Bravo-Ureta and Rieger (1991)
recorded positive relationship between economic efficiency and experience in a study of
dairy farms in New England. Wilson et al., (1998) also found a positive relationship
between experience and inefficiency in potato production in UK, implying that farmers
with fewer years of experience achieved higher levels of efficiency. The reason may be
that those with little experience are likely to seek out for new technology, unlike those
with experience. Rahman (2002) also reported similar results for Bangladesh rice
farmers. However, the same author registered a negative relationship between
inefficiency and experience for the same farmers (Rahman, 2003). In this study we
hypothesized a negative relationship between experience and profit inefficiency.
43
Classical economic theory recognizes specialization as a key determinant of efficiency.
Specialization implies optimal allocation of resources (time, money and human) in the
enterprise to improve productivity. In this case specialization in rice production by rice
farmers should lead them to seek better methods of production and hence improvement in
profits efficiency. Hence it was hypothesized that specialization ( ) in rice production
had negative impact on profit inefficiency levels.
3.5 Study Area, Data and Sources
3.5.1 Description of the Study Area
The data used in this study were collected from three districts in Uganda, namely Tororo,
Pallisa and Lira, in 2001(see Map Appendix C). Tororo and Pallisa are located in Eastern
Uganda and Lira is found in Northern Uganda. Tororo district occupies an area of 2,608.7
sq kms of which 8.87% is permanent wetlands. The district had a population of 536,888
with a sex ratio of 94.9.912 in 2002 population census and has one of the highest
population growth rates (3.05%). It had a population density of 346 people per sq km, far
above the national average of 126 people per sq km (UBOS, 2005). In Tororo district, the
data were collected from Doho rice scheme and the surrounding villages.
The Doho rice scheme, which was set up with the help of the Chinese Government, is
located in two of the six sub-counties of Bunyole County, that is, Kachonga and
Mazimasa sub counties, of Tororo district. The rest of the counties are Budumba, Busaba
and Butaleja. River Mpologoma, whose source lies on the slopes of Mt Elgon, drains the
12 Sex Ratio = no of males per 100 females or proportion of females in a given population.
44
area. The slopes have volcanic soils and through soil erosion, river Mpologoma carries
them down to the plains of Bunyole to form the wetlands on which rice fields are located.
The scheme is located in these wetlands and occupies an area of 828 hectares of land of
which 140 hectares is under cultivation. Most of the current rice farmers were allocated
the plots free of charge at the time when the scheme was set up while the government
provided technical services. The two sub-counties traditionally grew finger millet and
cassava as their main food crops and cotton as a cash crop. However, after the collapse of
the cotton industry, the two sub counties switched to rice. The rest of the residents of the
sub-county resorted to trading in what were formally food crops, such as sweet potatoes,
millet and groundnuts.
Pallisa district has an area of 1,991.7 sq. km, of which 337.6sq. kms (16.9%) is
permanent wetlands. These wetlands have not been surveyed to establish their potential
for rice production. A number of activities are carried out in these wetlands, such as
grazing animals, brick making, rice production and vegetable production. Many of these
activities are carried out at a micro scale and in an unorganized fashion. With the
provision of proper drainage and infrastructure, these wetlands could be turned into major
rice fields and could boost rice production for the country.
Until 1991, Pallisa district was part of the greater district called Bukedi. Bukedi
constituted the present three districts, namely Tororo, Pallisa and Busia districts. The
district had a population of 520,578 in 2002 population census with a sex ratio of 93.0
(UBOS, 2005). As in the case of Tororo, the district is experiencing the highest (3.24%)
45
population growth rates. The district traditionally cultivated finger millet and cassava for
food and cotton as a cash crop.
In Lira district, the study concentrated on Olweny rice scheme. Olweny rice scheme,
which was opened up much later, is located in Agwata sub-county, Dokolo County, in
Lira district. Lira district has an area of 7,200.7sq kms of which 4.13% are permanent
wetlands. In 2002 population census, the district had a population of 741,240 persons
with a sex ratio of 96.0. The district has one of the lowest population densities of 124
people per sq km. The main food crops were finger millet and sorghum and the cash crop
was cotton.
Olweny rice scheme was estimated to have a reclaimable land of 5,000 hectares of which
3,500 hectares is suitable for rice cultivation (CRS, 1982). The main food crops are finger
millet, sorghum and maize. The traditional cash crop is cotton. As in Tororo district,
cotton also lost out as a cash crop and the majority of the farmers switched to trading in
food crops such as sweet potatoes, millet, and simsim.
3.5.2 The Data
A structured questionnaire was used to collect primary quantitative data in the selected
households. The three districts (Tororo, Pallisa, Lira) were selected mainly because they
have been the major producers of rice in the country and for the period of 8 years (1993-
2000) accounted for 67 percent of the national output (UBOS, 2005). In addition, Lira
was specifically included in the sample for two reasons. First, to compare the
46
performance across the three districts and second, it is also an area, which is in search of
a viable cash crop, after cotton lost out as pointed out earlier.
The mode of selection of sample size in the three districts was dictated by the presence of
rice schemes in Tororo and Lira districts. In the two districts (Tororo and Lira), there was
a register of participating rice farmers kept at the scheme’s office that served as a
sampling frame. In case of Tororo district, large-scale farmers, who have opted to divide
up their farms in ¼ acre plots for rent to small-scale farmers, supplemented the scheme
register. Since these large farms are in the same locality near the scheme and in some
cases adjacent to the scheme, we felt it prudent to include farmers outside the scheme in
the sample. In this case, the landlords keep a register of the participating farmers in their
offices and this was used as a sampling frame for these types of farmers.
Olweny scheme rice register had mainly female farmers. This was due to the fact that the
scheme had initially, aimed at female farmers. However, at the time of the study, the
scheme had started to recruit male farmers, but these were not many. Therefore, in
addition to using random methods, purposive random sampling methods were employed
to include male farmers13.
In Pallisa, a different approach was adopted since there was no official register in
existence of small-scale farmers as in the case of Tororo and Lira districts. The assistance
of government officials, namely agricultural officers, was therefore enlisted. The major
rice growing sub-counties were identified and within these sub-counties major rice 13 The project recruited only female farmers at the beginning.
47
growing villages were purposively selected. The sub-counties selected were: Butebo,
Ikiki and Budaka. The villages selected were Lyama, Katiira in Ikiki sub-county;
Nabwali and Bokora in Budaka sub-county. Once the villages were identified, a village
register was used to draw the required sample. Where the village register did not exist,
the chairman/secretary’s assistance was solicited and a fresh register was compiled. The
sample was then randomly drawn using random numbers. In total, the survey covered a
sample of 297 farmers of which 253 were used in estimating the Translog model. The 44
farmers not included in the model were eliminated as outliers. The sample is distributed
as follows: Tororo (138), Pallisa (104) and Lira (55). The unevenness of the sample was
dictated by the availability of the required information each variable required to run the
translog model.
Data were collected on socio-demographics such as age, non-farm employment,
education, extension service visits, credit access, years in rice farming and degree of
specialization. For the stochastic frontier profit function, the relevant data collected were:
hired labor used in production of rice, fertilizers, and pesticides as other variable inputs
and their market prices. Family labor, land and capital were treated as fixed inputs. For
output, the relevant data collected included quantity of rice produced, sales, and prices at
which rice was sold for one season.
3.5.3 Data Reliability and Validity
In order to control for data reliability and validity, measurement and sampling errors; a
number of measurements were effected. The first measure taken was to pretest the
questionnaire in two of the districts. The instrument was tested in Tororo and Pallisa
48
districts. This was to ensure that the right questions were asked during the actual field
survey. The data obtained during the pre testing exercise were coded and analyzed to
gauge the accuracy of the questions. Second, the enumerators were then trained for one
week on how to administer the questionnaire through role-play. Third, while in the field,
the author participated in data gathering as well as supervising the field team.
Fourth, once data were captured, a number of tests were carried out to ensure getting
unbiased estimates. These tests included testing for normality of residuals using the One
Sample Kolmogorov-Smirnov test. The results suggest that, some variables did not
conform to the assumption of the regression analysis such as normality of the data. The
data that violated the normality assumption were transformed by use of logs. The results
are presented in Appendix A figures 1a-7b.
Outliers whose observations had large residuals were removed from the analysis such that
cases with studentized residuals greater than absolute value of 2 were excluded. In this
respect 13 observations violated this criterion and were therefore left out. Observations
whose central leverage values exceeded (2k +1)/n were deleted from the analysis (see
Appendix A for the print out). Out of a total of 297 cases 17 violated this assumption and
were deleted. Observations found to have an absolute value greater than n/4 were deleted
from the analysis. A total of 14 observations were deleted using this criterion. When all
abnormal cases were deleted 253 observations remained as the final data set.
Curve estimation procedure was employed for each predictor against the response
variable to verify for linearity; it was observed that all predictors were significantly and
linearly related to the dependent variable (F > 3.84; p < 0.000; R squared > 30.0 %).The
49
Variance Inflation Factor (VIF) method was used to detect multicollinearity and was
preferred over the correlation coefficient method which does not give conclusive results.
(Pindyck and Rubinfield,1981). No collinearity among the independent variables was
detected by the test since their specific values was less than 10.
The test for homogeneity of variance was conducted using Breusch-Pagan/Cook-
Weisberg test for heteroskedasticity , (www.stata.com, accessed 2nd April ,2004) and the
null hypothesis of constant variances of the residuals was accepted (p > 0.000).The
Ramsey test was conducted to test for omitted variables. The null hypothesis of no
omitted variables was accepted (F = 0.761).The Durbin-Watson test for independently
and identically distributed errors (iid) was calculated and from its value of less than 2 led
the conclusion that there was no problem with iid errors. In addition to the Komogrov-
Smirnov (K-S) test, the variables were corrected to normality using the skewness test as
shown in Table 3.4. The K-S test results are shown in Table3.3 and 3.4.Table 3.3 shows
unstadardized statistics while Table 3.4 shows standardized statistics. As the results show
in table 3.4 the assumption of normality of the data was upheld as shown by the K-S test
which states that the computed figure should not exceed 3. Other than hired wage rate, all
the variables included in the model have figures on Kurtosis of less than three (Table
3.4).
The traditional method of increasing reliability of estimates is to increase sample size.
Increasing the sample size has its own problems as reported by (Bakan, 1966). After
using a very large sample size (60,000 cases) the author observed that all statistical tests
were significant. He therefore concluded that there was a possibility that in the analysis
conducted, the significant values obtained could be attributed to either sampling errors or
50
the size of the sample. In order to test for this, “effect magnitude measures” was proposed
by (Maxwell & Delaney, 1990). The effect magnitude size is defined as the degree to
which the null hypothesis is false (Cohen, 1988). The null hypothesis is that the effect of
sample size is equal to zero. The decision is, if the Cohen d statistic is less or equal to 0.2,
the null hypothesis is rejected implying observed significance of estimated coefficients
were due to large size and sampling errors.
Table 3. 3: Skewness and Normality Variables (Unstandardized)- Translog Model
Statistics Profit Hired wage rate
Family wage
Other inputs
Rice Hectares
Capital Experience (years)
Mean 772.6 204.9 465.2 222.0 1.3 25491.2 11.7
S.E. 18.2 29.7 13.2 9.9 1982.2 .54
Std 114.3 313.7 512.4 223.7 1.7 34160.9 9.1
Variance in coefficient
3879420 98427 262597 50038 2.91166967247
83.3
Skewness 12.7 3.4 3.9 3.4 6.1 7.6 1.4
Kurtosis 193.5 14.9 25.4 16.9 56.7 88.7 2.3
Minimum -311.5 .00 10.0 10.0 .05 00 1.0
Maximum31187.0 2239.3 4860.0 1929.4 20.5 46000 51.0
Source: computed from Field survey
51
Table 3. 4: Skewness and Normality Variables (Standardized)- Translog Model
Statistics Profit Hired
wage
rate
Family
wage
Other
inputs
Rice
Hectares
Capital Experience
(years)
Mean 6.09 4.95 5.67 5.02 -0.17 9.75 2.14
S.E. .06 0.08 0.06 0.05 0.05 0.05 0.05
S.D 1.09 1.22 1.06 0.89 1.02 0.87 0.86
Variance in
Coefficient1.19 1.51 1.14 0.81 1.04 0.77 0.75
Skewness -0.16 -1.01 -0.68 -0.26 -0.46 0.06 -0.44
Kurtosis 1.17 3.81 0.85 0.07 0.45 0.48 -0.24
Minimum 2.3 -1.29 2.3 2.3 -3.0 6.91 0
Maximum 10.4 7.71 8.49 7.56 3.02 13.04 3.93
Source: computed from Field survey
The results of the computed presented Cohen’s d statistic using results from the MLE
(translog model) estimates of equation 11 and 12 are presented in Table 3.5. The test
results show that the Cohen static is greater than 0.2 for most of the variables therefore
the null hypothesis is accepted for almost all the variables included in equation 11 and12.
It is concluded that the probability of the values observed on the estimated coefficients
were neither due to chance nor sample size influence, that is, they are true values.
52
Table 3.5 Effect Magnitude Measures for the MLE result Estimates
Variables Coefficient t-ratio Cohen d statisticConstant 7.65 15.2 30.4Cost of hired labor 0.12 1.71 23.42“Other inputs” -0.02 -3.27 -6.54Imputed cost of family labor -0.28 -25.5 -0.51Rice hectares 0.05 7.26 14.52Capital 0.13 4.22 8.44Cost of hired labor x “other inputs” -0.03 -1.62 -3.24Cost of hired labor x Imputed cost of family labor
-0.01 -1.71 -3.42
Cost of hired labor x rice hectarage 0.02 1.19 2.38Cost of hired labor x capital 0 0.43 0.86“Other inputs” x Imputed cost of family labor
0 0.04 0.09
“Other inputs” x rice hecatrage 0.13 3.24 6.48“Other inputs” x capital 0.03 1.74 3.48Imputed cost of family labor x rice hectarage -0.04 -1.52 -3.04Cost of family labor x capital 0.04 2.72 5.44Rice hecatarage x Capital -0.05 -2.68 -5.36Cost of hired labor2 0.01 1.84 3.68“Other inputs”2 -0.02 -1.23 -2.46Imputed cost family labor2 -0.01 -1.12 -2.24Rice hectarage2 -0.01 -4.33 -8.66Capital2 -0.03 -4.03 -8.06Constant -2.75 -7.91 -15.82Non-farm employment -0.32 -1.82 -3.64Education 0.16 2.67 5.34Experience 0.32 7.52 15.04Credit access 0.37 2.37 4.74Extension services 0.24 1.86 3.72Degree of specialization 0.23 3.67 7.34Source: Computed from Survey data
The K-S test suggested by Armstrong and Eperjesi (2000, 2002) like the t test, has the p
value representing the probability that the observed difference between the two data sets
(e.g. Tororo and Pallisa) could have arisen by chance. The criterion is the value lies p <
0.05 or p < 0.10 is used to reject or accept the null hypothesis. Table 3.6 shows that
samples from the three districts (Tororo Pallisa and Lira) are independent and do not have
the same distribution.
53
Table 3. 6: Tests of Significance using Two-Sample Kolmogorov-Smirnov Test
District Kolmogorov-Smirnov Z P values
Tororo- Pallisa 2.134 .000
Tororo- Lira 2.842 .000
Pallisa- Lira 2.010 .001
Source: computed from survey data
3.6 Data Analysis/Model Implementation
The stochastic profit frontier function equation 11 and the Inefficiency equation 12 were
estimated using FRONTIER 4.1 computer package. The estimation responded to
objectives 2, 3, and 4. The program combines the two-stage procedure into one and
effects the maximum likelihood estimates of the parameters of a stochastic profit frontier
function. The procedure is as follows:
1) A two-phase grid search of γ is conducted, with the β parameters (excepting β0) set the
OLS values and the β0 and σ2 parameters adjusted according to the corrected ordinary least
squares formula as set in Coelli (1995). Any other parameters (μ,η or δ’s) are set to zero
in this grid search.
2) The values selected in the grid search are used as starting values in an iterative
procedure (using the Davidon-Flecher-Powell Quasi-Newton method) to obtain the final
likelihood estimates (Coelli, 1996a).
The likelihood function is expressed in terms of the variance parameters, σ2 = +
and γ = / (Rahman, 2002, 2003).
54
This procedure has been hailed as being more superior to the two-stage procedure by a
number of researchers because it does not violate the assumptions made about the
distribution of inefficiency effects (error terms μ and ν) that they are independently and
identically distributed (Battesse and Coelli, 1995; Coelli, 1996b; Abdulai and Huffman,
2000 and Rahman, 2002) .
55
CHAPTER IV
RESULTS AND DISCUSSION
4.0 Introduction
The purpose of this chapter is to present socio-economic characteristics of the farmers in
study area, the econometric results from the frontier profit function and the results of the
inefficiency model. The first part of the chapter presents socio-demographic results which
respond to objective number one of this study. This is followed by a discussion of results
from the log likelihood test presented (LL) presented in Table 4.2. The results show that
the C-D model is not an adequate representation of the data and hence, necessitated
estimation of a frontier translog model. The presentation of the findings from the Cobb-
Douglas (C-D) model is therefore presented in the Appendix A for any reader interested
in this part of the results.
The discussion of log likelihood results is followed by results from the translog models
(Equation 11 and the inefficiency model (Equation 12). This was designed to respond to
objectives number 2 and 3 .Objective number 2 was designed to estimate a translog profit
frontier while objective number 3 examined specific factors influencing inefficiency
levels among individual rice farmers.
4.1 Socio Demographic and Socio Economic Characteristics
Table 4.1a shows socio-demographic characteristics of the households studied in the
three districts. The means of the relevant variables in the three districts were tested to see
whether they significantly different. The superscripts indicate their level of significance.
Where the superscripts are the same, for example age, which has the same superscript for
56
the three districts, implies that there are no statistical differences. However, if the
superscripts are different, this implies that the means tested are significantly.
On the whole, the respondents lie in similar age categories (with the mean of 41 years for
both Tororo and Lira and 40 years for Pallisa), but are not significantly different.
Although Tororo district has the largest average household size of 9 persons as compared
to 8 for Pallisa and Lira districts, again these are not significantly different.
The average land holding for the three districts is 1.77, 2.88 and 2.02 hectares for Tororo,
Pallisa and Lira, respectively. Out of this, 70 percent is under crop cultivation in Tororo
and Pallisa districts and 58 percent in Lira. The low level of crop cultivation in Lira
district could be explained by lack of oxen, which used to be the major mode of
cultivation before the ongoing civil unrest in the region. Lira has the smallest area under
rice (0.21 ha) as compared to Tororo (0.57 ha) and Pallisa (0.72 ha) as expected and are
significantly different from the other two districts under study. This is in line with the fact
that Lira is a new entrant into rice production.
The use of family labor in rice production is highest in Pallisa district (219.32 person
days/ha) followed by Tororo district (178.27 person days/ha), and Lira district (218.13
person days/ha). This may reflect the level of commercialization in the latter two
districts. Indeed, Tororo’s labor cost per hectare is far higher than that in the other two
districts. Input costs that only reflect expenditure on fertilizers, chemicals, and pesticides
are again highest in Tororo, with the average of Ushs 55,677 per hectare as opposed to
Ushs 41,115 per hectare in Pallisa.
57
Generally, there was at least one plot of rice per household, but Tororo district had
slightly more (2) plots than the other two districts that had (1) each (Table 4.1a). This was
expected because Tororo was one of the initial districts that benefited from Government’s
policy of promoting rice production in the country. This is also reflected in experience
levels. Tororo district had the highest number of years (15) in rice production followed
by Pallisa (12 years) and Lira (5 years) and are significantly different.
Table 4.1a: Selected Socio-economic Characteristics of Farmers in the study area
Characteristics Tororo Pallisa LiraMean Mean Mean
Age of household head (years)
41.09a
(1.22)140.02 a
(1.39)41.22a
(1.43 )
Household size 9.37 a
(0.47)8.41 a
(0.49)8.36 a
(0.66)Number of children 6.42a
(0.35)5.36 bc
(0.31)5.40 ac
(0.38)Size of land (Ha) 1.77 a
(0.12)2.87 b
(0.34)2.02 a
(0.20)Total (Ha) 1.25 a
(0.08)2.14 b
(0.20)1.13 a
(0.10)Rice (Ha) 0.57 a
(0.04)0.72 b
(0.09)0.18 c
(0.02)Imputed family labour cost Ha (Ush)
137475.47a
(44.57)101518.50b
(94.59)117682.50c
(22.86)Hired Labour cost per Ha (Ush)
57280.66 a
(6035.95)46994.06 a
(9010.90)10374.81 b
(1575.41)“other input cost” per Ha (Ushs)
4897.57 a
(1255.92)2557.73 a
(926.12)2895.13 a
(852.01)Experience (years) 14.71 a
(0.81)12.16 b
(0.96)4.75 c
(0.30 )Degree specialization 3.23a
(0.09)3.90b (0.11)
3.56c
(0.15)Number of plots 1.72 a
(0.09)1.21 bd
(0.05)1.12 cd
(0.05)n 138 104 55
Source: Computed from Field Survey Data.Superscripts with the different letters are significantly different at the 0.10 level1 () figures in brackets are standard errors
58
Table 4.1b shows results of some other variables, which could not be presented in the
preceding Table because of its categorical nature. Table 4.1b reveals that Tororo district
had the lowest level of education with 51 percent of the respondents having attended
primary education as compared to Lira, which had 60 percent in the same category,
although not significantly different. Credit access by rice farmers in all three district was
poor; with maximum of 56 percent in Lira district indicating so. Yilma (1996) had made
the same observation for coffee producers in Masaka district who also had poor access.
Note that the informal avenue constitutes the largest (77.4%) source of loans for those
who accessed them. This may be because these sources are easily accessible with
minimum transaction costs and conditions, even though the interest rate could go as high
as 50% per year.
The situation of access to extension services is equally very discouraging, with only 20%
of the farmers being able to access extension services. Descriptive results indicate very
few prospects for non-farm employment in the areas studied. Indeed, only 27% of the
respondents indicated that they were engaged in non-farm employment activities. Pallisa
district seems to have the best opportunities (31%) among the three districts followed by
Tororo (28%) and Lira (18%).
59
Table 4.1b: Other Household Characteristics in the Study Area
Characteristics Tororo Pallisa Lira
Proportion Proportion Proportion
Primary
0.507 a
(0.043)
0.683 bc
(0.046)
0.600 ac
(0.067)
Secondary / Tertiary
0.275 a
(0.038)
0.212 a
(0.040)
0.236 a
(0.058)
Not attended
0.217 a
(0.035)
0.106 bc
(0.030)
0.164 ac
(0.050)
Credit Access0.355 a
(0.041)0.481 ac
(0.049)0.564 bc
(0.067)Credit from informal
source0.857 a
(0.045)0.98 b
(0.045)0.774 a
(0.056)
Non-farm employment0.28a
(0.04)0.31a
(0.04)0.18a
(0.06)n
138 104 55Source: Computed from Field Survey Data.Superscripts with the different letters are significantlydifferent at the 0.10 level1 () figures in brackets are standard errors
4.2 Testing for the Appropriateness of C-D Model
The likelihood ratio, sigma-squared, gamma parameters shown in Tables 4.2 and 4.3a
through 4.3d presents are results on the behavior of the error term outlined in equation
12. Basically, the statistics are designed to test for efficiency effects in the model and the
appropriateness of the model to represent the data. The gamma () and the log likelihood
(LL) parameters are employed to test for efficiency and the appropriateness of the model,
respectively. The gamma () tests whether the observed variations in efficiency are
simply random or systematic. The parameter is defined as the ratio of the unexplained
inefficiency error term of ( ) to the total sum of errors, explained ( ) and random ( )
or = / ( + ). The gamma () is bounded by 0 and 1, where if is zero
60
inefficiency effects are not present in the model, and if it is one inefficiency exists and is
not random. In other words, if is not significantly different from zero, the variance of
the inefficiency model in equation 12 reduces to average response function (C-D function
or deterministic model) in which the inefficiency variables enter directly into the model
(Battese and Coelli, 1995).
The results in Table 4.3a through 4.3d show that gamma () is significantly different
from zero in all the estimated samples implying that there is profit inefficiency in rice
production. The observed variations in profit efficiency among the rice farmers are due
mainly to differences in farm practices and characteristics of sampled rice farmers rather
than random factors.
The LL test statistic is employed to further provide tests to various restrictions in the
model. The restrictions are normally effected according to the researcher’s demands. In
this study, we wanted to establish three positions, namely whether we can use a C-D
model instead of any other form of the model, in this case, the translog to estimate
equations 11 and 12. We also wanted to know whether farmers were operating on the
frontier and whether factors included in model 13 explained the observed profit
inefficiency.
The restricted frontier model as specified by the null hypothesis is defined as LL = -2{log
[Likelihood (H0)]-log [Likelihood (H1)]}
where LL is absolute values between LR and LU.
LR (H0) is the restricted frontier (C-D model) function in
the null hypothesis;
61
and LU(H1) is the unrestricted ( stochastic) frontier function in the alternate. The test
statistic has approximately a distribution with equal to the number of parameters,
which are assumed to equal zero in the null hypothesis.
The first null hypothesis in Table 4.2 is set to find out whether a C-D model can be
employed in estimating the two equations (11 and 12) or a translog specification. The LL
test for this hypothesis is conducted using the log-likelihood function values of the
estimated stochastic frontier function and the values of the corresponding C-D profit
function. The rejection criterion is set at 5% such that when the product of the difference
between the two (restricted and unrestricted) LL is greater than the critical value, the
value obtained from Kode and Palm (1986) the null hypothesis is rejected in favor of the
alternate (the translog specification). When this happens, it implies that the C-D model is
not adequate, necessitating the need to use the alternative model, in this case the translog
specification model. The second hypothesis tests various restrictions on joint and
inefficiency effects included within the two models 12 and 13. In the first instance, we
test whether farmers individually are operating at the frontier. If they are, then we reject
null hypothesis at the fixed critical confidence level, got from Kode and Palm (1986), in
this case 5% and accept the alternate. This would imply that farmers are profit inefficient
or are not operating on the frontier.
The third hypothesis is designed to test the contribution of factors included in model 12
to observed inefficiency levels (Table 2), in case hypothesis 2 is rejected. The null
hypothesis to test is that factors included in model 12 contribute significantly to observed
profit inefficiency levels. Again, at the set critical point, of 5% level, the difference
62
between the LU (model 11 plus model 12 estimated simultaneously) and the restricted
LR (inefficiency effects specified in model 12) is greater than the critical value got from
Kode and Palm (1986). Hence the null hypothesis is rejected. Rejecting the null
hypothesis implies that these factors contribute significantly to explaining the observed
profit inefficiency.
The results presented in Table 4.2 indicate that the null hypothesis for adequacy of the C-
D model form is rejected at 5 per cent level of significance in all models. This implies
that we should select the translog specification instead of the C-D specification and hence
that is what was selected. The second hypothesis is also rejected indicating that the rice
farmers are not operating on the frontier. Similarly, the third hypothesis is rejected
implying that the variable play a significant role in explaining the observed inefficiency.
To conclude this section, the three hypotheses tested show that first, the C-D model is not
an adequate representation of the data, second, that all farmers are not operating on the
efficient profit frontier and third, that in general the variables included in inefficiency
model adequately explain the observed variations. Therefore, the next section
concentrates on estimating the translog profit function using MLE method.
63
Table 4.2: Hypotheses Testing for the Models and its Inefficiency Effects
Hypotheses Pooled Sample Tororo Pallisa Lira
1) H0:C-D is an adequate representation of Profit frontier Function
LLU -80.13 -19.41 55.48 17.14
LLR -127.44 -47.91 26.80 -10.34LL 94.62 57.00 29.68 27.48
Critical value*(5%)
13.40 13.40 13.40 13.40
Decision reject H0 reject H0
reject H0 reject H0
2) H0: = 0 = d =0, d
Each farm is operating on profit frontier
LLU -80.13 -19.41 55.48 17.14
LLR -186.04 -81.97 -59.07 -29.77LL 212.22 125.12 211.10 93.82Critical value(5%)
10.37 10.37 10.37 10.37
Decision reject reject reject reject
3) H0: 0 = d =0, d
Variables included in the inefficiency effect model have no effect on the level of profit inefficiency.
LLU -80.13 -19.41 -55.48 17.48
LLR -166.23 -72.15 -45.74 -18.15LL 86.10 105.48 101.2 35.29Critical value(5%)
13.40 13.40 13.40 13.40
Decision reject reject reject rejectSource: Field Survey Data.*the corresponding critical values were obtained from Kodde and Palm (1986) LLR and LLU Likelihood function values of the restricted and unrestricted function, respectively.LL computed Likelihood Ratio Value which is the absolute difference between LLU and LLR multiply by 2
64
4.3 Estimation of Frontier Profit Function: Translog Model
As explained in chapter 3, the estimation of the stochastic frontier profit function
(objectives 2) was undertaken. The dependent variable was restricted profit from an
output of one season. Estimation was done in two phases: first using the pooled sample
data and then using district level samples, individually. The pooled sample included all
the three district samples in the study sites, namely Tororo, Pallisa and Lira. The results
for the pooled sample and the district specific samples are presented in Tables 4.3a
through 4.3d. The discussion concentrates on MLE results.
All the estimated coefficients in the pooled sample (MLE) carry the theoretically
expected signs in the MLE model and are statistically significant, except in the case of
estimates associated with “other inputs”(Table 4.3a). Similarly, estimates associated with
all the five variables were statistically significant in Tororo sub-sample (Table 4.3b).
However, estimates on cost of hired labor carried unexpected positive sign. In Pallisa
sub-sample, the estimates for all the five variables were statistically significant and
carried the theoretically expected signs (Table 4.3c). In the Lira sub-sample, three
variables namely “other inputs”, area under rice and capital were statistically significant
(Table 4.3d). However, although estimates on cost of hired labor have negative sign, it is
not significant.
A comparative analysis of coefficient estimates for the three districts show that costs of
“other inputs”, area under rice and capital are the most influential variables in rice
production (Tables 4.3a through 4.3d). The estimates associated with these three
variables were statistically significant. Costs of “other inputs” affect profit efficiency
negatively whereas area under rice and capital has the opposite influence.
65
Table 4.3a: Frontier Profit Function among Rice Producers in selected Districts Dependent Variable = Normalized Profit in UgShs
OLS MLE
Coefficients p-v1 Coefficients p-v1
Constant 7.04 0.00 8.11 0.00Cost Hired labor ( ) -0.14 0.09 -0.12 0.03
“Other inputs” ( ) -0.01 0.74 -0.01 0.67Imputed cost of family labor (Ushs/ha) ( )
-0.12 0.00 -0.20 0.00
Rice acreage ( ) 0.17 0.00 0.09 0.00
Capital ( ) 0.02 0.07 0.02 0.05
x -0.01 0.74 -0.03 0.07
x -0.02 0.18 0.01 0.07
x 0.02 0.41 0.03 0.15
x 0.03 0.04 0.02 0.12
x -0.08 0.09 -0.05 0.14
x 0.00 0.89 0.09 0.07
x 0.02 0.58 0.03 0.18
x 0.05 0.31 0.01 0.78
x 0.04 0.20 0.04 0.07
x -0.03 0.47 -0.07 0.03
x -0.01 0.67 0.01 0.15
x 0.02 0.41 0.01 0.44
x 0.02 0.46 0.00 0.89
x 0.02 0.60 -0.04 0.18
x 0.03 0.13 -0.03 0.01Sigma-squared 0.24 0.27 0.00Gamma 0.69 0.00Log likelihood -
166.2280.13
n 253Source: Field Survey data.p-v1 are p values computed from t-ratios (source: Abramowitz and Stegan.http://www.graphpad.com) Hand book of Math functions .
Imputed cost of family labor also play an important role in profit efficiency in the three
districts, except in Lira in which it carries a pervasive (positive) sign. The negative sign
66
on the estimated coefficient for this variable in two districts (Tororo and Pallisa) and the
pooled sample imply negative impact on profitability of the rice enterprises. Many of the
studies reviewed earlier, such as Ali and Flinn (1989), Abdulai and Huffman (2000) and
Rahman (2003) reported similar results.
The estimated coefficients on costs of “other inputs”, which included costs of fertilizers
and seeds and insecticides, are statistically significant and carry a negative sign in all
results. Also, the estimated coefficients on capital have the positive expected sign and are
statistically significant in all districts (Tables 4.3b through 4.3d).
67
Table 4.3b: Frontier Profit Function among Rice Producers in Tororo District
Dependent Variable = Normalized Profit in UgShsOLS MLE
Variables Coefficients p-v1 Coefficients p-v1
Constant 7.25 0.00 7.37 0.00Cost of hired labor ( ) 0.00 0.89 0.14 0.00
“Other inputs” ( ) -0.05 0.14 -0.03 0.00Imputed cost of family labor (Ushs/ha) ( )
-0.06 0.18 -0.22 0.00
Rice hectarage( ) 0.14 0.00 0.03 0.00
Capital ( ) 0.00 0.89 0.08 0.00
x -0.00 0.84 0.00 0.64
x -0.02 0.46 0.00 0.55
x 0.07 0.18 0.03 0.00
x 0.03 0.41 0.00 0.78
x -0.05 0.74 -0.09 0.00
x 0.16 0.56 0.05 0.55
x -0.01 0.88 -0.01 0.67
x 0.13 0.30 0.06 0.05
x 0.07 0.30 0.04 0.01
x 0.17 0.46 -0.08 0.12
x -0.02 0.18 -0.02 0.00
x 0.03 0.69 0.09 0.00 x -0.03 0.47 0.03 0.01
x -0.28 0.14 -0.15 0.00
x -0.62 0.74 -0.01 0.01
Sigma-squared 0.55 0.00Gamma 55.48 1.00 0.00Log likelihood -72.15 -19.41n 123Source: Field Survey Data.p-v1 are p values computed from t-ratios
68
Table 4.3c: Frontier Profit Function among Rice Producers in Pallisa District
Dependent Variable = Normalized Profit in Ug Shs
OLS MLE
Variables Coefficients p-v1 Coefficients p-v1
Constant 6.51 0.00 6.56 0.00Cost of hired wage ( ) -0.06 0.46 -0.03 0.00
“Other inputs”( ) 0.00 0.85 -0.01 0.00Imputed cost of family labor (Ushs/ha) ( )
0.01 0.89 -0.02 0.00
Rice hectarage ( ) 0.17 0.00 0.04 0.00
Capital ( ) 0.05 0.34 0.02 0.00
x -0.06 0.46 0.00 0.44
x -0.02 0.47 -0.02 0.12
x 0.12 0.07 -0.01 0.44
x 0.07 0.07 0.01 0.18
x 0.04 0.78 0.10 0.00
x 0.40 0.41 0.16 0.15
x -0.07 0.85 0.11 0.01
x -0.02 0.86 -0.08 0.07
x -0.05 0.65 -0.06 0.00
x -0.22 0.47 -0.04 0.07
x -0.04 0.03 0.00 0.44
x 0.05 0.89 -0.15 0.03 x 0.02 0.68 0.01 0.00
x -0.55 0.03 -0.03 0.44
x 0.01 0.85 -0.02 0.14
Sigma-squaredGamma 1.00 0.00Log likelihood -45.74 55.48n 91Source: Field Survey Data.p-v1 are p values computed from t-ratios
69
Table 4.3d: Frontier Profit Function among Rice producers in Lira District
Dependent Variable = Normalized Profit in Ug Shs
OLS MLE
Variables Coefficients p-v1 Coefficients p-v1
Constant 19.64 0.89 89.25 0.00Cost of hired labor ( ) -3.3 0.74 0.00 0.91
“Other inputs”( ) 7.64 0.44 -7.43 0.00Imputed cost of family labor (Ushs/ha) ( )
-9.53 0.05 1.81 0.01
Rice hectarage ( ) 8.68 0.44 8.94 0.00
Capital ( ) 0.05 0.00 0.30 0.05
x -0.36 0.62 -0.03 0.91
x 0.02 0.47 0.06 0.18
x 0.57 0.01 0.14 0.30
x 0.30 0.00 -0.01 0.67
x 2.03 0.00 0.48 0.05
x -4.19 0.18 2.32 0.00
x -3.96 0.00 1.77 0.00
x -1.48 0.00 -0.99 0.00
x -0.87 0.02 -0.55 0.00
x 1.78 0.74 -1.60 0.00
x -0.15 0.03 0.00 0.91
x 2.17 0.00 -1.21 0.00 x 0.06 0.09 0.06 0.30
x 1.60 0.58 0.93 0.00
x 0.94 0.34 -0.31 0.00
Sigma-squared 0.14 0.00Gamma 1 0.00Log likelihood 18.15 17.14n 39
Source: Field Survey Data.p-v1 are p values computed from t-ratios
To determine the level of profit efficiency (objective 3), two hypotheses were examined
to determine whether rice farmers were operating on the frontier or not. If not, how far
was each farmer operating from the frontier? The response to this question can be
70
gleaned from the value of (γ). In all cases, the value of ( is close to one indicating that
there is inefficiency or that farmers were not operating on the frontier. How far away a
given farmer was operating from the frontier is the subject of the next section.
4.4 Profit Efficiency Score Estimates: Translog Model
The frequency distribution of farm-specific efficiency scores for the rice farmers is
presented in Table 4.4 and figure 9 (Appendix A). The findings show that in the pooled
sample, rice farmers achieved on average 66 percent level of efficiency (Table 4.4).
Taking separate samples, Pallisa district had the highest mean (75 percent) efficiency
levels followed by Lira (70 percent) and Tororo district (65 percent).
Table 4.4: Frequency Distribution of Farm- Specific Profit Efficiency Index in
Studied Areas-Translog Model
Pooled Tororo Pallisa LiraEfficiency Index
Freq. % Freq. % Freq. % Freq. %
<30 27 11 18 15 14 15 06 1531-40 12 5 14 11 04 04 05 1341-50 32 13 11 09 00 0 02 0551-60 31 12 12 10 07 08 02 0561-70 18 7 10 81 08 09 00 071-80 34 13 13 11 04 04 04 1081+ 99 39 45 37 53 58 20 51n 253 100 123 100 91 100 39 100
Mean 66.4 64.7 74.5 70.3Min 04 04 02 10Max 95 1.00 1.00 1.00S.D. 22.6 27.0 27.3 30.8Source: Computed from the Survey Data
71
A wide variation in the level of efficiency is observed across the three districts ranging
from 02 percent to 100 percent. It is worthy noting, however, that this wide variation is
not unique to Uganda. Similar results have been reported by other researchers elsewhere.
Abdulai and Huffman’s (2000) study of rice farmers in four districts in Northern Ghana
reported a wide variation in the level of efficiency for rice farmers that ranged from 16
percent to a maximum of 95.5 percent. In Asia where the rice crop has a long history of
production and intensive research activities, researchers obtained similar results. Ali and
Flinn (1989) obtained a minimum of 13 percent and a maximum of 95.5 percent for rice
farmers of Gujranwala district, Pakistan. Other authors, including Ali and Sha (1994),
and Wang et al., (1996b) for Punjab Pakistan, North-west Pakistan, and China,
respectively registered similar variations. While Wang et al., (1996b) reported efficiency
levels ranging from 6 per cent to 93 per cent with a mean of 62 per cent and Ali et al.,
(1994) registered a mean profit efficiency of 75 per cent with a range of 4 per cent to 90
per cent. Studies by Rahman (2002, 2003) that covered rice farmers in Bangladesh also
reported a wide variation in profit efficiency, ranging from 3.3 percent to 93.7 percent
with a mean of 60 per cent for modern Aman14 rice. These similarities may be a reflection
of the low level of economic transformation of many of the third world peasant
economies where rice is grown.
The distribution of the efficiency in the translog model as illustrated in figure 9(Appendix
A) show skeweness to the right in all cases, implying that in all the districts, the sampled
rice farmers, although operating below the frontier, over 30 percent are operating close to
the frontier.
14 Aman is one of the three seasons in Pakistan which is the monsoon .The other two are Aus and Boro which are dry season. These two seasons were combined and the efficiency recorded varied from 11.5 percent to 92.2 percent (Rahman, 2003).
72
The inefficiency translated into a profit loss ranging from Ug shs 74,261 to 509,871 with
a mean of Ug shs 137,741 per acre per season for the pooled sample (Table 4.5). Tororo
experienced the highest loss (Ushs 489,692) followed by Pallisa (Ugsh 301,571) and Lira
(Ushs 364,162). Further, the Kolmogorov-Smirnov test showed that there were
significant differences between the three districts in terms of mean profit loss. The most
significant difference was that between Tororo and Pallisa (Table 4.6).
Table 4.5 Comparison of mean Profit loss per hectare as a result of Profit Efficiency by Districts
District Mean n Std. Deviation Minimum Maximum
Tororo 489692.50 123 11719.3852 469514.00 509871.00
Pallisa 301571.00 91 11915.3694 281271.00 321664.00
Lira 114304.00 39 24029.4971 74261.00 154347.00
Total 364162.03 253 137741.79 74261.00 509871.00
Source: Field Survey Data.
Table 4.6 Tests of Significance of Mean Profit loss
District Kolmogorov-Smirnov Z P-values
Tororo- Pallisa 7.232 .000
Tororo- Lira 5.442 .000
Pallisa- Lira 5.225 .000
Source: Computed from Field Survey Data.1 used Kolmogorov-Smirnov Test
In addition to profit loss, the degree of responsiveness or price elasticity was computed
and results are presented in Table 4.7. For example the results show that a 1% increase in
cost of “other inputs” in Tororo district would result into a decrease of 0.03% in profits.
73
A 1% increase in area under rice in the same district would result into 0.03 percent
increase of profit.
Table 4.7 Estimated Profit Elasticities in the studied Area
Tororo Pallisa Lira
Prices and Fixed Inputs Price
elasticity
p-v1 Price
elasticity
p-v1 Price
elasticity
p-v1
With respect to
Cost of hired labor 0.14 0.00 -0.03 0.00 0.00 0.91
“other inputs” -0.03 0.00 -0.01 0.00 -7.43 0.00
Imputed cost of family
labor
-0.22 0.00 -0.02 0.00 1.81 0.01
Area under rice 0.03 0.00 0.04 0.00 8.94 0.00
Capital 0.08 0.00 0.02 0.00 0.30 0.05
Source: Computed from profit function resultsp-v1 are p values computed from t-ratios
4.5 Determinants of Firm-Specific Profit Inefficiency in Rice-Translog Model
In line with objective number 3, estimated results based on model 12 are presented in
Table 4.8. The purpose was to determine factors that explain profit inefficiency. The
variables included in the model were in line with theory as explained in chapter 3. These
are: non-farm employment, education, experience in rice growing, degree of
specialization, access to credit and extension services.
The presentation of the results is by variables. Results on the non-farm employment
variable carry opposite signs in the three districts. This is in line with what was
hypothesized in chapter 3. In two districts (Pallisa and Lira), the estimated coefficients
74
carry a negative sign and are statistically significant. Abdulai and Huffman (2000)
reported similar results for rice farmers in Northern Ghana. Ali and Flinn (1989), Wang
et al., (1996b) and Rahman (2002, 2003) reported similar results for farmers in Pakistan,
China and Bangladesh, respectively. The results indicate that having non-farm work
provides the income to buy inputs needed to raise productivity, and hence reducing
inefficiency. On the other hand, in Tororo district, the estimated coefficients carry
positive sign, but not statistically significant.
Table 4.8: Determinants of Farm-Specific Inefficiency in Rice Production in the Sampled Districts
Dependent Variable = Inefficiency μ
Pooled Tororo Pallisa Lira
Coeff p-v1 Coeff p-v1 Coeff p-v1 Coeff p-v1
Constant ( ) 2.09 0.00 3.84 0.00 3.51 0.00 2.28 0.00
Non-farm employment ( ) 0.37 0.01 0.06 0.89 -0.95 0.03 -0.93 0.00
Education ( ) -0.14 0.00 -0.25 0.00 -0.16 0.00 -0.30 0.00
Extension services( ) -0.16 0.00 -0.26 0.00 -0.47 0.00 -0.28 0.03
Credit access( ) -0.25 0.15 -0.55 0.05 -0.46 0.03 -0.24 0.44
Experience ( ) -0.07 0.67 -0.44 0.17 -0.49 0.00 0.06 0.78
Degree of specialization( ) -0.08 0.00 -0.14 0.00 -0.15 0.00 -0.03 0.17
Source: Field Survey Datap-v1 are p values computed from t-ratios
75
The results also show that the estimated coefficient on education is negative and
statistically significant in all the districts, indicating reduction in profit inefficiency. This
implies that to an extent more education brings about decrease inefficiency (increase in
efficiency) in rice production. These results are consistent with Lockheed et al., (1980),
Ali and Byerlee (1991), Ali and Flinn (1989), Bravo-Ureta and Rieger (1991), Abdulai
and Huffman (2000) for rice farmers in Ghana and Wang et al., (1996b) for China. Thus,
giving education to rice farmers in particular would be very beneficial in terms of
reducing inefficiency in rice production. Reduction in profit inefficiency will enhance the
Government’s policy on commercialization of agriculture and poverty eradication.
The estimated coefficients associated with the extension services are significant in all
districts. These results show that access to extension advice by rice farmers help to
reduce the profit inefficiency in rice production. The results are also consistent with
findings obtained by other researchers (Bravo-Ureta and Rieger, 1991; Seyoum et al.,
1998; Rahman, 2002). These results therefore serve to emphasize the role of extension
services in reducing profit inefficiency in rice production.
Access to credit is expected to ease the financial constraint, enhance the acquisition of the
much-needed inputs, and improve revenue and subsequently profits. Indeed, the results of
the Tororo and Pallisa districts show that access to credit is a significant factor in
reducing inefficiency in profits. The estimated coefficients associated with experience
carry the expected negative sign and are statistically significant at 10 percent level in all
the districts. The studies reviewed by Ali and Byerlee (1991) reported similar results and
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Rahman (2002) registered similar results for Bangladesh rice farmers. Sharma et al.,
(1999) studying allocative and economic efficiencies in swine production in Hawaiian
farmers had similar results. The results imply that those with experience will be better
performers than those without. Whereas this is so, education and quality of extension
services given to the farmers would supplement or in some cases substitute it.
When a farmer specializes in rice production, all his/her efforts in terms of accessing
information on new technology should translate into improvement of efficiency in the
production of the crop. In this study a negative and statistically significant relationship
between the degree of specialization in the rice crop production and profit inefficiency
was observed in districts of Tororo and Pallisa implying efficient allocation of resources
in these districts. Abdulai and Huffman (2000) registered similar results for rice
producers in Northern Ghana. However, in Lira the results are not significant, possibly
because the crop is still new and as such specialization in the crop is low.
4.6 Key Constraints to Profit Efficiency in Rice Production
The previous section examined factors contributing to profit inefficiency among rice
producers. The main purpose of this section is to analyze key factors contributing to
profit inefficiency in rice production loss. Section 4.4 showed that rice farmers lost on
average Ug shs 302,744 per hectare due to inefficiency in rice production. However, the
results did not clearly indicate which of the variables led to this profit loss. The results
presented in Tables 4.9a through 4.9c shed some light on this. The discussion combines
all the 3 Tables discussing variable by variable. It was noted that education plays a key
77
role in actual profit made by rice farmers. The loss in profit by farmers by not going to
school ranged from Ushs131, 000 to Ushs 524, 000 per hectare in Tororo district and
Lira, respectively (Table 4.9a-4.9c). These results also show that farmers with tertiary
education significant gain of revenue throughout the three districts. The loss was
71,000/=, 245,000/=, 286,000/= per hectare in Lira, Pallisa and Tororo, respectively.
Similarly, the revenue loss between those who have had primary education and tertiary
education are significantly different. However, there were no significant differences in
loss of revenue between those who are literate and those who have This implies that we
require farmers to go beyond primary leaving level to be more effective in utilizing
opportunities to improve revenue in rice production.
In terms of efficiency, education s translated into efficiency reduction. For example, in
Tororo district, those farmers who had tertiary education were more efficient (50%) than
those who had no education (46%) (Table 4.9a) and these differences are significantly
different. Similar results are observed across the two remaining districts.
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Table 4.9a Profit Loss in Rice Production in Tororo District by Key Constraints
Parameters Actual Profit 000’s Shs
Profit loss 000’s Shs
Efficiency Scores
Education Level
n Mean Mean Meannone 24 968.6 a
(3.8)524 a
(3.7)45.9 a
(2.5)primary 61 962.6 a
(2.3)489 b
(2.3)49.2 b
(1.6)secondary 33 953.5 b
(3.2)451 c
(3.2)52.7 c
(2.1)tertiary 5 637.0 c
(10.6)286 d
(8.1)50.1 d
(5.5)
Credit AccessYes 43 1104.0a 467 a 57.7 a
No 80 1069.5b 523 b 51.1 b
Extension services
Yes 22 1114.4a 487 a 56.3 aNo 101 1118.1b 549 b 50.9 b
Degree of specialization
0-25% 34 815.4a
(17.6)515.5 a
(2.7)59.1 a
(0.5)25.1-50% 55 1081.4 b
(20.4)514.8 a
(3.5)57.4 a
(0.9)50.1+ 34 1281.4 c
(17.6)507.1 b
(5.5)55.3 b
(1.2)Source: Field Survey Data.
Different superscripts along columns depict significant differences at the 0.10 level.
The results on access to credit help to reinforce earlier observation that those who had
access to credit in all districts experienced least loss in profit as compared to those who
didn’t have. The farmers’ loss ranged from Ushs 73,000 per hectare (Lira district) to Ug
shs 467,000 (Tororo district) (Table 4.9a-4.9c). These results indicate that having access
to credit would improve profit efficiency in Tororo and Pallisa districts from 42% to
56% and 47% 53%) for Pallisa. Efficiency would increase from 50% to 53% in Lira.
Note that these improvements are statistically significant at 10% level.
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Table 4.9b Profit Loss in Rice Production in Pallisa District by Key Constraints
Education level
n Actual profit000’s Ushs
Profit loss000’s Ushs
Efficiency
Education
Nil 8 672.4 a
(7.4)351 a (6.3)
47.8 a (1.5)
Primary 64 659.5b
(2.2)337 b (2.2)
48.9 a (0.5)
Secondary 17 574.6 c
(4.6)281c
(4.3)51.1 b (1.1)
Tertiary 2 523.5d
(29.2)245 d
(12.6)53.2 a (3.1)
Credit AccessYes 41 615.6a 269 a 56.3 a
No 50 586.8b 338 b 42.4 b
Extension access
Yes 8 711.9 a 294 a 58.7 a No 83 645.8b 361b 44.1 b
Degree of specialization
0-25% 36 1091.3a
(17.6)513.9a
(4.1)57.9a
(0.9)25.1-50% 33 1137.8a
(20.4)508.2b
(4.7)57.1a
(1.2)50.1%+ 22 924.8b
(18.5)499.8c
(6.9)55.1b
(1.5)Source: Field Survey Data.
Different superscripts along columns depict significant differences at the 0.10 level.
Similarly, farmers who had access to extension services were significantly better off than
those without in that they experienced lower revenue (Table 4.9a-4.9c). Their loss ranged
from Ushs 87,000 (Lira district) to Ushs 487,000 per hectare (Tororo district). However,
unlike in education, there would be marginal improvement in increase of profit efficiency
level through access to extension services. Tororo and Pallisa would experience
improvement of 5points from (51% to 56% in Tororo district and 44% to 59% in Pallisa
district) whereas Lira, farmers had the least increase (48% to 50%).These differences are
statistically significant at 10% level. The reason could be that even though farmers had
80
access to extension services, the messages may have not been relevant, since messages
were not crop specific. Until very recently, NARO, the organization charged with the
responsibility of generating technologies for farmers had in the past attached low priority
to rice, especially paddy. In terms of policy, there is need to realize that there is a very
big percentage of farmers depending on this crop for their livelihood. The crop therefore
deserves special attention in terms of budget allocation (research as well as human) to
generate high yielding varieties for dissemination. Results indicate that there are
statistical differences between farmers who specialize in rice in the three districts.
Table 4.9c Profit Loss in Rice Production in Lira District by Key constraints
Education level
n Actual profit000’s Ushs
Profit loss000’s Ushs
Efficiency
Education
Nil 8 199.1a
(4.9)131 a (2.4)
34.2 a (1.7)
Primary 23 237.3b
(2.6)126 b (1.4)
46.9 b (1.0)
Secondary
6 191.3 a (6.1)
97c
(2.8)49.3 c b
(2.0)Tertiary 2 153.7c
(20.0)71 d (4.9)
53.8 c d
(3.4)
Credit AccessYes 21 155.0 a 73 a 52.9 a
No 18 307.5b 155 b 49.6 b
Extension accessYes 20 174.7 a 87 a 50.2 a
No 19 323.8 b 169 b 47.8 b
Degree of specialization
0-25% 15 1151a 510 a 59.4a
25.1-50%
17 1056a 514a 58.2a
50.1+ 7 975.5b 521a 57.6b
Source: Field Survey Data.Different superscripts along columns depict significant differences at the 0.10 level.
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4.6 Summary
This chapter presented both descriptive and econometric results. Since the likelihood test
statistic showed that the translog model was a better choice, the study concentrated on
presenting and discussing results from the translog model. These results showed that area
under rice and capital had positive effect on profit levels in all the three districts. On the
other hand, costs of “other inputs” exerted negative influence on profit efficiency in the
three districts under study. In addition, imputed cost of family labor played an important
role in Tororo and Pallisa districts only.
The next level of analysis concentrated on computing farm-specific profit scores. The
results revealed a wide variation in profit efficiency among sampled rice farmers ranging
from 02 per cent to 100 percent in the three districts. Pallisa district had the highest score
of profit efficiency with a mean of 74.5 percent level of efficiency and the percentage of
the farmers who scored above 61 per cent was 71.4. Pallisa was followed by Lira with a
mean score of 70 per cent and Tororo with a mean score of 64.7 percent. The potential
for improving profit efficiency in production of rice by adopting the best frontier
technology is possible in all districts. For example the rice farmers in Tororo need to
improve on agronomic practices by 36 percent to move to the frontier while in Pallisa and
Lira the required improvement would be 25 and 30 per cent, respectively. The next level
of analysis examined factors contributing to observed level of inefficiency.
Six inefficiency effects (variables) were included in the inefficiency model. These were
non-farm employment, education, and access to extension services, credit access, and
82
experience in years of production of rice and degree of specialization in rice production.
The findings showed that overall; education and access to extension services were the
most influential variables on profit levels. These two variables act as a catalyst in
improving efficiency. The degree of specialization in rice production had a negative
influence in Tororo and Pallisa districts only.
A deeper analysis of the constraints showed that farmers on average lost Ushs 302,744
per hectare due to inefficient production. However, the results indicated that education,
credit and extension access contributed significantly to explaining the observed level of
inefficiency. Credit access is hence important for maintaining high profits. Farmers lose
most profit when they lack education. They lose up to Ushs 524,000/=, 467,000 and
487,000 per hectare for lacking education, access to education and extension services,
respectively.
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CHAPTER V
SUMMARY, CONCLUSIONS AND POLICY RECOMMENDATIONS
5.0 Introduction
This study set out to evaluate profit efficiency levels among rice producers in Eastern and
Northern Uganda. Since rice is the number one crop in terms of returns to labor and is
inceasingly becoming a major food crop, especially in institutions such as schools and
hospitals, its profit efficiency levels are very crucial to the attainment of both food and
income security for farmers.
Rice has faced stagnating yield levels in the past five years (1997-2004), possibly
reflecting low research priority previously accorded to the sub-sector. Thus, the main
questions addressed in this study were first, whether rice farmers are producing at the
production frontier. Second, if not how this translates into profit levels, and exploration
of the main determinants of profit levels in rice production. Third, an assessment of
factors affecting profit efficiency levels among rice producers in Eastern and Northern
Uganda. Fourth, an investigation of how much profit was being lost due to allocative and
technical inefficiency.
Chapter one gave the background information of the whole study and stated the main
objectives. In chapter two, the theoretical exposition of the economic efficiency
measurements and the theoretical modeling was undertaken.
84
Generally, the literature reviewed in chapter two highlighted the fact that there are two
main strands in the theoretical developments in frontier modeling to handle efficiency
measurements. These are frontier and non-frontier approaches. The frontier approaches
aim at locating the “best practice” profit function and through either deterministic or
stochastic models, farmer-specific profit efficiency levels are estimated. In non-frontier
approaches, location of “best practice” isoquant is not required and non-parametric
methods such as mathematical programming or Data Envelopment Method can be used to
estimate a profit function and inefficiency levels.
The literature reviewed also highlighted the fact that the efficiency levels estimated
depend on the approach used. In the case of deterministic models, all the observed
inefficiencies are attributed to differences in farmers’ practices, whereas in the stochastic
model, there is an error term that is split between the observed () and the unobserved ()
components. The observed inefficiency () is interpreted as inefficiencies due to
technical and allocative inefficiencies of individual farmers and the unobserved () is
attributed to random factors, such as weather and policy changes.
In the second part of chapter two, theoretical modeling for the study is discussed. This
study discussed the stochastic frontier translog profit function model by Ali and Flinn
(1989) and Rahman (2002 and 2003). Briefly, the model states that the normalized profit
of farm j (defined as gross revenue less variable cost divided by farm specific price for
rice) is a function of prices of variable inputs, fixed inputs, dummy variables for
85
exogenous factors and an appropriate error term. This model was specified fully together
with the inefficiency model and estimated simultaneously.
In chapter three we discussed the empirical model, data sources, and definitions of
variables. The data used were collected from three districts namely Tororo, Pallisa and
Lira from a sample of 253 rice farmers. The study adopted a translog model suggested by
Ali and Flinn (1989) and Rahman (2002 and 2003). The variables used in the empirical
model were; normalized profit on the jth farm as a dependent variable, imputed cost of
family labor, normalized cost of hired labor and cost of “other inputs” as variable costs.
Rice hectares and capital were modeled as fixed factors. In the inefficiency model, the
variables were; profit inefficiency for jth farm as a dependent variable and the
independent variables were non-farm employment, educational level, extension services,
credit access, years of farming (experience), and degree of specialization.
The maximum-likelihood estimates of the parameters of the translog stochastic function
and inefficiency effects were estimated by using FRONTIER 4.1; Coelli (1996a). This
package estimates the two models simultaneously. To test for the functional form, the
respective log likelihood tests were computed and the results compared with the critical
values obtained from Kodde and Palm (1966). The tests carried out were to assess
whether there was a need of using a more sophisticated model such as a translog instead
of the C-D model. Also tested, were various restrictions on the role of parameters and
inefficiency effects. Furthermore, profit efficiency levels were computed followed by the
estimation of profit losses due to profit inefficiency. Based on the estimates of the profit
86
frontier function, the basic features of production structure were computed, namely profit
elasticity with respect to price of inputs.
5.1 Summary The results of the Log likelihood tests showed that the C-D model was not the right
model necessitating the adoption of a frontier translog model. Thus the profit frontier
translog model was estimated in this study.
The analysis from the translog model showed that the variables rice hectarage and capital
had a positive influence on the profit levels while imputed cost of family labor and costs
of “other inputs” had a negative effect on profit efficiency levels in all studied areas.
The analysis of profit efficiency levels revealed that the sampled farmers from all the
three districts (Tororo, Pallisa and Lira) were not operating at the profit frontier. They
had different levels of efficiency, with a wide variation (2%-100%) and a mean of 66
percent. Pallisa district scored the highest mean level (74.5%) with about 70 per cent of
the farmers scoring 61 per cent and above. These results imply that Pallisa district had the
highest potential for improving efficiency levels or moving the farmers to operate on the
profit frontier, in this case by 25 per cent. The efficiency levels in the remaining two
districts were 65 per cent and 70 per cent in Tororo and Lira districts, respectively.
87
Further analysis of profit loss due to allocative and technical inefficiency showed that
farmers in Tororo experienced the highest loss (Ushs 489,692/=) followed by Pallisa
(Ushs 301,571/=) and Lira (Ushs 114,304/=). The elasticity estimates showed that,
reduction on costs in “other costs”, expansion in area under rice, and investing in capital
would have the greatest positive impact on profits.
In analyzing the sources of inefficiency of rice farmers, six factors were identified. These
were non-farm employment, education, experience, access to credit, access to extension
services and degree of specialization in rice growing. Non-farm employment had
opposite signs in the three districts, but in two districts (Pallisa and Lira) had negative
sign and statistically significant. These results implied that those who accessed non-farm
employment in these districts could have used the income earned to purchase inputs to
increase productivity and hence reduce inefficiency in rice production.
Lack of education was found to have an impact on profit inefficiency levels in all the
three districts. Lack of it contributed to the loss of profit efficiency by as much as 10
points . The significant differences were observed between those who are illiterate and
those who have at least primary education. The implication is that to improve efficiency
in rice production primary level of education is absolutely necessary.
Lack of extension services was found to be statistically significant and influencing profit
inefficiency negatively in all districts. These results reinforce the already acknowledged
88
view that extension access is a necessary lubricant to adoption of new technology, which
has positive impact on profit efficiency. The most crucial point is to pass on the relevant
messages to farmers. In the crop under study case, such information was found to be
limited as the crop has in the past received very low priority in terms of budget allocation
(research and human). It is recommended that NARO- an organization charged with the
responsibility to carry out research on crops such as rice to refocus its efforts on rice. In
addition, the organization should foster linkages with private sector to come in where
they are weak, particularly in providing credit or supplying seed.
The degree of specialization in rice production was found to be an important variable in
influencing profit inefficiency levels in Tororo and Pallisa districts. The results tend to
suggest that specialization in rice production reduces profit inefficiency in Tororo and
Pallisa districts implying efficient use of resources on specialization. In these two district
it would pay for the farmers to specialize the crop.
Credit access was found to be a significant factor in reducing inefficiency in Tororo and
Pallisa districts. Farmers who did not have access to credit lost as much as Uganda Shs
549, 000 per hectare in Tororo district and 338,000/= in Pallisa district. The efficiency
levels were 6 points below those who accessed in both districts. Experience as a factor
was important in Tororo and Pallisa districts. Farmers with experience in rice production
were more efficient than those without.
89
5.2 Conclusions and Policy Recommendations
The main objective of this study was to estimate a frontier profit function for rice
producers in Eastern and Northern Uganda. The subsidiary objectives were to determine
farm-specific profit efficiency levels and explain inefficiency levels observed. The study
results from the frontier profit function showed that the major variables affecting profit
efficiency were imputed wage of family labor and area under rice. Imputed cost of family
labor had a negative influence on profits whereas area under rice had the opposite effect.
These results, therefore, imply that in order to improve profit levels in rice production
there is need to increase area under rice and reduce family labor in rice production.
Currently, rice farmers in the study area are operating an average of 0.57, 0.72 and 0.21
hectares in Tororo, Pallisa and Lira districts, respectively. But area expansion may imply
increasing family labor, which negatively affects profit efficiency. Thus, this suggests
that land-augmenting technologies such as improved seeds would be the most appropriate
approach. This serves to re-emphasize the need for research stations to strengthen the
breeding programs in order to come up with high yielding varieties for release to rice
farmers. The recent release of upland varieties (NARIK 1, 2, 3) is hence very
encouraging (NARO, 2003). Similar efforts are required for lowland rice.
The study results also showed that the majority of rice farmers were not operating on the
profit frontier, given the technology and that there was potential to do so by eliminating
the observed inefficiencies. The variables found to explain the profit inefficiency levels
among rice producers were lack of extension services and low educational levels.
90
Therefore, if rice farmers have to reduce profit inefficiency, which implies moving to the
profit frontier, access to extension services by rice producers must be improved. The
results in this study help to reinforce the government’s policy of bringing extension
services nearer to the farmers.
In the context of rice production, the Ministry of Agriculture Animal Industry and
Fisheries (MAAIF) and NARO should not only focus research on upland rice, but also on
low land rice in terms of instituting a breeding program for new varieties of rice. Without
this, extension officers will have limited knowledge to disseminate to rice farmers. Also,
given the low educational levels in all the three districts, the Government policy on
Universal Primary Education (UPE) requiring all school going children to attend school
is in the right direction. However, this policy may not succeed unless special strategies
are put in place to discourage children from dropping out from school due to the urge to
make quick cash in rice gardens.
Lastly, to reduce profit inefficiency levels in all districts the issue of non-farm
employment must be tackled. One way is create employment opportunities outside the
farm. This would enable some of the farmers to access jobs from which they can earn
income. The income would be used to purchase inputs to use on the farm and hence
improve on productivity. Alternatively, they need not stay on the farm, but could
combine non-farm activities effectively by employing labor-saving technologies to ease
the weeding and bird-scaring burdens. This implies that the concerned organizations
should come up with varieties which are less palatable to the birds. This would help to
91
reduce on the drop out of school going as these are the ones who are mainly employed to
perform this ardors task.
5.3 Recommendations for Further Research
This study is one of a few studies the author is aware of that has pursued a rigorous
analysis of efficiency issues in the production of agriculture commodities in selected
districts of Uganda. Appleton and Balihuta (1996) studied the impact of education on
agriculture and Yilma (1996) studied technical efficiency issues in Masaka district.
Therefore, there is need to replicate the current study in other districts for the whole
country. With the country well underway in implementing the Plan for Modernization of
Agriculture, which emphasizes commercialization of agriculture, it may also be necessary
to conduct such studies for other crops in Uganda.
Furthermore, this study covered lowland rice areas only. Hence, the scope needs to be
widened to cover the upland rice. Secondly, to know what is happening to efficiency
levels, we need good panel data on the crop to trace the impact of the technology
generated on productivity. This can only be possible when longitudinal studies are carried
out systematically. Finally, this study limited itself to commodity production issues, yet
marketing and consumption issues are equally important in improving profit efficiency of
rice farmers. Thus a study to examine rice marketing issues is pertinent.
92
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APPENDIX A
1. DATA NORMALIZATION
100
101
102
103
104
8
8
105
106
----------------------------------------------------------------------------------------------------
107
REGRESIÓN DIAGNOSTICS
Ramsey RESET test using powers of the fitted values of ln_profit Ho: model has no omitted variables F(3, 221) = 0.0818 Prob > F = 0.761
Breusch-Pagan / Cook-Weisberg test for heteroskedasticity Ho: Constant variance Variables: fitted values of ln_profi
chi2(1) = 0.0673 Prob > chi2 = 0.942
VIF
Variable VIF 1/VIF----------------+--------------------------beta15 | 7.3400 0.1363beta14 | 7.1337 0.1608beta12 | 6.9273 0.1853beta10 | 6.7210 0.2098beta_9 | 6.5147 0.2344beta_6 | 6.3083 0.2589beta11 | 6.1020 0.2834beta20 | 5.8957 0.3080beta18 | 5.6893 0.3325beta17 | 5.4830 0.3570beta13 | 5.2767 0.3816beta_7 | 5.0703 0.4061beta_1 | 4.8640 0.4306beta16 | 4.6577 0.4551beta_8 | 4.4513 0.4797beta_4 | 4.2450 0.5042beta_2 | 4.0387 0.5287beta_5 | 3.8323 0.5533beta19 | 3.6260 0.5778delta_6 | 3.4197 0.6023beta_3 | 3.2133 0.6269delta_2 | 3.0070 0.6514delta_4 | 2.8007 0.6759delta_3 | 2.5943 0.7004delta_5 | 2.3880 0.7250
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delta_1 | 2.1817 0.7495delta_7 | 1.9753 0.7740--------------+------------------------Mean VIF | 4.5545
.
. Shapiro-Wilk W test for normal dataVariable | Obs W V z Prob|>z|--------------+------------------------------------------------------ln_profi | 253 0.99060 1.72000 1.26200 0.10349beta_1 | 253 0.99086 1.67292 1.15065 0.13600beta_2 | 253 0.99111 1.62585 1.03931 0.16851beta_3 | 253 0.99137 1.57877 0.92796 0.20102beta_4 | 253 0.99163 1.53169 0.81662 0.23353beta_5 | 253 0.99189 1.48462 0.70527 0.26604beta_6 | 253 0.99214 1.43754 0.59392 0.29855beta_7 | 253 0.99240 1.39046 0.48258 0.33106beta_8 | 253 0.99266 1.34338 0.37123 0.36357beta_9 | 253 0.99292 1.29631 0.25988 0.39608beta10 | 253 0.99317 1.24923 0.14854 0.42859beta11 | 253 0.99343 1.20215 0.03719 0.46110beta12 | 253 0.99369 1.15508 -0.07415 0.49361beta13 | 253 0.99395 1.10800 -0.18550 0.52612beta14 | 253 0.99420 1.06092 -0.29685 0.55862beta15 | 253 0.99446 1.01385 -0.40819 0.59113beta16 | 253 0.99472 0.96677 -0.51954 0.623648beta17 | 253 0.99497 0.91969 -0.63088 0.65615beta18 | 253 0.99523 0.87262 -0.74223 0.68866beta19 | 253 0.99549 0.82554 -0.85358 0.72117beta20 | 253 0.99575 0.77846 -0.96492 0.75368delta_1 | 253 0.99600 0.73138 -1.07627 0.78619delta_2 | 253 0.99626 0.68431 -1.18762 0.81870delta_3 | 253 0.99652 0.63723 -1.29896 0.85121delta_4 | 253 0.99678 0.59015 -1.41031 0.88372delta_5 | 253 0.99703 0.54308 -1.52165 0.91623delta_6 | 253 0.99729 0.49600 -1.63300 0.94874delta_7 | 252 0.99972 0.05100 -6.93200 1.00000
2. Estimation of Frontier Profit Function: Cobb-Douglas Model
Below is a brief discussion of results from C-D model. Table A1 summarizes Ordinary
OLS and MLE results for the C-D profit function model. The coefficients for all the
variables (Cost of hired labor, imputed cost of family labor, area under rice capital, “other
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input costs” in a pooled sample carry the theoretically expected signs and are statistically
significant with exception cost of hired labor (Table A1). In Tororo district, the estimated
2coefficients associated with three variables, namely “other inputs”, imputed wage of
family labor and rice hectares are statistically significant and carry the theoretically
expected signs for both OLS and MLE results (Table A2).
The Pallisa district results are shown in Table A2. Of the five variables included in the
model, four variables were significant and carried the expected signs in MLE estimation
techniques. The estimates associated with cost of hired labor, “other inputs” costs and
imputed family labor costs carried negative signs. Area under rice and capital had
positive signs. Note that all the estimates associated with the preceding discussed
variables are statistically significant. In Lira district, only three variables of the five
included in the model were significant and carried the expected sign. These were “other
inputs”, area under rice and capital.
Table A1: Coefficient Estimates of C-D Frontier Profit Function in all three
studied Districts
Dependent variable = Normalized Profit in Ug ShsVariables OLS MLE
Coefficients p-v coefficients p-v1
Constant ( ) 6.96 0.00 7.43 0.00
Cost of hired labor (Ushs /Ha) ( ) -0.03 0.17 -0.01 0.17
“Other input costs” (Ushs/Ha) ( ) -0.03 0.00 -0.02 0.07
Imputed cost of family labor -0.11 0.00 -0.12 0.00
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(Ushs/Ha) ( )
8Area under rice (ha) ( ) 0.20 0.00 0.13 0.00
Capital ( ) 0.02 0.01 0.02 0.07
Sigma –squared - 0.31 0.00
Gamma - 0.63 0.00
Log likelihood -186.65 -127.44
Source: Field Survey Data.p-v1 are p values computed from t-ratios
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Table A2: Coefficient Estimates of C-D Frontier Profit Function-Tororo District
Dependent Variable = Normalized Profit in Ug Shs
Variables OLS MLE
Coefficients p-v1 coefficients p-v1
Constant ( ) 7.20 0.00 7.89 0.00
Cost of hired labor (Ushs /Ha) ( ) -0.02 0.47 0.00 0.91
“Other input costs” (Ushs/Ha) ( ) -0.04 0.06 -0.05 0.00
Imputed cost of family labor
(Ushs/Ha) ( )
-0.06 0.00 -0.08 0.00
Area under rice (Ha) ( ) 0.16 0.00 0.10 0.00
Capital ( ) 0.00 0.89 0.00 0.91
Sigma –squared 0.23 0.89 0.03
Gamma 0.92 0.00
Log likelihood -81.99 -47.91
Source : Field Survey Datap-v1 are p values computed from t-ratios
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Table A3: Coefficient Estimates of C-D Frontier Profit Function-Pallisa District
Dependent Variable = Normalized Profit in Ug Shs
Variables OLS MLE
Coefficients p-v1 coefficients p-v1
Constant ( ) 5.94 0.00 6.78 0.00
Cost of hired labor (Ushs /Ha) ( ) 0.04 0.09 -0.03 0.00
“Other input costs” (Ushs/Ha) ( ) -0.01 0.67 -0.02 0.00
Imputed cost of family labor
(Ushs/Ha) ( )
-0.01 0.65 -0.02 0.03
Area under rice (Ha) ( ) 0.18 0.00 0.05 0.00
Capital ( ) 0.02 0.63 0.01 0.17
Sigma –squared 0.23 0.40 0.00
Gamma 0.99 0.00
Log likelihood -55.08 26.80
Source: Field Survey Data.p-v1 are 2p values computed from t-ratios
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Table A4: Coefficient Estimates of C-D Frontier Profit Function-Lira District
Dependent Variable = Normalized Profit in Ug Shs
Variables OLS MLE
Coefficients p-v1 coefficients p-v1
Constant ( ) 20.51 0.01 20.02 0.00
Cost of hired labor (Ushs /Ha) ( ) -0.06 0.15 -0.01 0.67
“Other input costs” (Ushs/Ha) ( ) -1.28 0.00 -1.03 0.00
Imputed cost of family labor
(Ushs/Ha) ( )
0.06 0.60 0.08 0.52
Area under rice (Ha) ( ) 1.41 0.00 0.96 0.00
Capital ( ) 0.66 0.00 0.12 0.15
Sigma –squared 0.32 0.38 0.05
Gamma 0.95 0.00
Log likelihood -29.77 -10.32
Source: Field Survey Data.p-v1 are p values computed from t-ratios8
2.2 Profit Efficiency Score Estimates
Table A5 and figure 8 show the distribution of farm-specific profit efficiency model
results of the C-D model. The efficiency levels were obtained by getting the exponential
of scores from the estimates of inefficiency model 12. The results show a wide variation
of efficiency levels in the districts, with 24 farmers in the sample getting less than 40 per
cent level of efficiency and 66 per cent getting over 81 %( Table A5). This is in contrast
114
to translog model results, which registered only 30%. Within the districts, Tororo has the
highest mean score of 79 per cent followed by Pallisa at 75 per cent and Lira at 65 per
cent. Again, these results demonstrate that the translog results are superior. Figure 8
shows this clearly by the fact that the scores are skewed positively. What contributes to
the observed levels of efficiency is the subject of the next discussion.
Table A5 Farm Specific Efficiency Scores in a Profit Frontier C-D model
Efficiency Scores
Pooled Tororo Pallisa Lira
n % n % n % %<40 24 9.4 8 6.5 13 14.29 9 23.141-50 6 2.3 5 4.07 5 5.49 4 10.351-60 17 6.7 2 1.62 5 5.49 2 5.161-70 20 7.9 0 0 9 9.89 4 10.371-80 20 7.9 22 17.89 2 2.20 3 7.781+ 166 65.6 86 69.92 57 62.63 17 43.6n 253 100 123 100 91 100 39 100Mean 77.2 79 75 65Min 9.1 02 04Max 95.0 98 96Source: Field Survey Data.
2.3 Determinants of Farm-Specific Profit Inefficiency in Rice-C-D Model
The purpose of this section is to explain the variation in performance by farmers of the
above observed profit efficiencies. The results presented in Table A6 suggest that the
results are at variant with those reported in translog model. Generally, the same variables
have not performed well. Whereas education and extension service estimates are
significant in all the three districts in translog model, they are significant in Tororo and
Pallisa (education) and Pallisa (extension services). Degree of specialization has major
influence in Tororo and Pallisa in translog model whereas it was only so in Pallisa in C-D
model. Non- farm employment carries expected negative sign in Pallisa and Lira in
translog model but had little influence in all districts in C-D model. Similarly, experience
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had influence in Pallisa district in translog model but only so in Tororo district.in C-D
model.
Table A6: Determinants of Firm-Specific Profit Inefficiency in Rice Production-
C-D model
Dependent: Variable = Inefficiency effects (μ)
Pooled Tororo Pallisa Liracoefficients p-v1 coefficients p-v1 coefficients p-v1 Coefficients p-v1
Constant (
)4.10 0.001 2.84 0.16 3.14 0.00 1.07 0.18
Non-farm
employment
( ) 0.14 0.46 -1.55 0.91 -0.78 0.12 0.46 0.46
Education (
)-0.24 0.00 -0.34 0.03 -0.16 0.00 -0.17 0.17
Extension
services ( )-0.14 0.00 0.19 0.77 -0.50 0.00 -0.25 0.18
Credit
Access ( )-0.27 0.17 -1.40 0.03 -0.32 0.00 -0.02 0.91
Experience
(yrs) ( )-0.19 0.14 -0.46 0.14 -0.27 0.17 -0.07 0.95
Degree of specialization ( ) -0.21 0.03 -0.50 0.12 -0.16 0.00 -0.14 0.17Source: Field Survey Data.p-v1 are p values computed from t-ratios
116
Figure 8: Profit Efficiency Distribution C-D Model
117
Figure 9: Profit Efficiency Distribution Translog Model
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APPENDIX B
QUESTIONNAIRE
PROFIT EFFICIENCY AMONG RICE PRODUCERS IN EASTERN AND
NORTHERN UGANDA
Introduction:
Rice is slowly gaining prominence both as a means of livelihood and the diets of
Ugandans. It is more prominent in the Eastern Uganda. However, there exists limited
knowledge on the crop.
The purpose of this study is to evaluate profit efficiency in rice production
Please note that your responses will remain confidential.
Name of Enumerator----------------------------------------------------------------------------------
Date of Interview--------------------------------------------------------------------------------------
District---------------------------------------------------------------------------------------------------
Sub country---------------------------------------------------------------------------------------------
Village/parish-------------------------------------------------------------------------------------------
SECTION A
SOCIO-DEMOGRAPHIC
Respondent name and number-----------------------------------------------------------------------
119
1. Respondent sex. Male/Female
2. Head of household Yes No
3. How many are you in the household including non-biological? No-------------------------
No. of adults No. Children <18
Males Females Males Females
4. Please, fill the following table with the information regarding the household.
Member of
household
Age
(years)
Education
level
Main
occupation
No. of
years
Secondary
occupation
No. of
years
120
SECTION B:
RICE PRODUCTION
5. How much land (total) do you have? No. of acres---------------------------------------------
6. How much of this land was occupied by agricultural crops last season?-------------------
7. When did you start growing rice? Year----------------------------------------------------------
8. How many plots of rice do you have? No.------------------------------------------------------
9. What is the area of the plots and who owns them?
Plot Area/acres Type of ownership
1.
2
3
4
10. How did you/they get the plots?
Plot Source of ownership
1
2
3
4
11. How many of these did you cultivate this year? No------------------------------------------
121
12. Who in the family carried out the following agricultural activities in the plots
mentioned above in the last season?
Children <18 years
Activity School going Not going to
school
Hsl Head Spouce1 Spouce2 Spouce 3 male female male female
Opening land
Seed bed
prep
Planting
Weeding
Scaring bird
Harvesting
Threshing
Marketing
122
13. How many days did the member of the household take in each activity?
Number of working days in the week
Member of the family
Activity Hsld
head
Spouce1 Spouce2 Spouce3 Children <18years
School going Not going
Male Female Male Female
Opening of
land
Seed bed
preparation
Planting
Weeding
Scaring birds
Harvesting
Threshing
123
14. Did you hire labor in rice activities last season? Yes/No. If yes, for what activities
and how many days and if paid in cash, at what rate?
No. of days Hired labor
Activity Plot 1 Plot 2 Plot 3 Plot 4 Wage rate (shs)
8
8
15. Did you use inputs (fertilizers, manure, pesticides) in your rice last seasons?
Yes/No
16. If yes which ones did you use and how much in each plot?
Plot Type (Quantity Units and Price)
1
2
3
4
17. If no, why?-----------------------------------------------------------------------------------------
------------------------------------------------------------------------------------------------------------
------------------------------------------------------------------------------------------------------------
124
18.What farm implements did you use in rice production?
Type of equipment Number owned Year bought Value when bought shs.
Hoes
Pangas
Ox plough
Basket
Wheel barrow
Others (specify)
19. Are there any crops you grow that compete directly with rice directly? Yes/No
20. If yes, in which way? (be specific or explain).
Crops Land Time Labour
125
SECTION C: HARVESTING AND STORAGE
21. How many bags of rice did you harvest last season? No. of bags--------------------------
22. How many bags of these did you sell last season? Unmilled
------------------------------------------------------------------------------------------------------------
Milled----------------------------------------------------------------------------------------------------
------------------------------------------------------------------------------------------------------------
23. Did you store any last season after harvest? Yes/No
24. If yes, in which form did you store.
1) Unmilled 2) milled ..3) both……
25. Which containers did you sue to store (Tick)
1) Gunny bags 2) Floor 3) Traditional granary 4) others (specify)
26. How long did you store last season? (Tick)
1) Sold straight away 20 1 month after 3) 1-2 months 4)>2 months
27. What are the main problems you face in storage (mention them in order of
importance)?
1)--------------------------------------------------------------------------------------------------
2)--------------------------------------------------------------------------------------------------
3)--------------------------------------------------------------------------------------------------
4)-------------------------------------------------------------------------------------------------
28. How did you dry your un-milled rice last season?
1) on bare grounds 2) on mats 30 cemented area 40 others specify
29. If cemented, how much did it cost you to do so and when did you do it?
Ushs…………………year……………………………………………..
126
30. If mats, how many and how much did you pay and when did you buy them?
Ushs……………….year………………………………………………….
31. Did you get any credit (formal or formal) to use in rice production last season?
Yes/No.
32. If yes, fill the following table
Last season
Type of credit Formal Informal
From where/whom
Amount
Interest rate
33. If no, why not
-------------------------------------------------------------------------------------------------------
34. Did an extension officer visit you about rice production last season? Yes/No.
35.If yes, how many times last year? 1) Once a month 2) 3 times a month 3)Once
in 6 months 4) Not at all.
36. If visited, what message did they carry?
Message
--------------------------------------------------------------------------------------------------
37. If they did not come, did you try to look for advice from extension agents?
Yes/No
127
38. If yes, what type of information did you look for and from whom?
Type of information Media (source)
39. Apart from extension agents how else do you get information on production of
rice?
1) Radio 2) neighbor 3) newspapers 4) family
40. What type of information did you get?
Type of information Source
128
SECTION D: MARKETING
41.In which form did you market your rice last season?
1) un milled 2)milled 3) both depending on need of funds
42. Last season where do you market it?
1) Traders came to my home 2) took to the mill 3) took to the local
market
4) Used any of the methods depending on convenience.
43. If traders came to your home, what price did you get per kilo on average?
1) Un milled Ush/kg……………..2) Milled rice ……..Ushs/kg
44. How far is the market from your home? No of miles----------------------------------------
45. If you took to the market, what price did you get per kg?
1) Before milling Ush/kg-------------------------------------------------------------------
2) After milling Ushs./kg-------------------------------------------------------------------
46.. Are there times when you fail to market your milled rice? Yes/No.
47. If 2yes, what do you think are the reasons?
------------------------------------------------------------------------------------------------------
129
APPENDIC C: MAP SHOWING STUDY DISTRICTS
Lira
Pallisa
Tororo
130