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Greener
Journal of Agricultural Sciences Vol. 10(2),
pp. 103-113, 2020 ISSN:
2276-7770 Copyright
©2020, the copyright of this article is retained by the author(s) |
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Impact of Improved Wheat Technology
Package Adoption on Productivity in Oromia Regional State, Ethiopia
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Ethiopian
Institute of Agricultural Research, Addis Ababa, Ethiopia
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ARTICLE INFO |
ABSTRACT |
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Article
No.: 090919168 Type: Research |
This study examines the impact of adoption
of improved wheat technology package (including improved wheat varieties,
information regarding improved wheat management practices as well as
artificial/chemical fertilizer) on productivity using 837 sample farm households
in Oromia Regional State, Ethiopia. Propensity score matching (PSM)
technique was employed since it is an increasingly utilized standard
approach for evaluating impacts using observational data of a single period.
It is found that full adoption of improved wheat technology package appears
to significantly increase productivity growth on the average by 61 to 67%
for farm households in the study area. Thus, the study recommends that full
adoption of improved wheat technology package could be an effective strategy
to enhance productivity and, thereby, production that contributes a lot to
the structural transformation of the Ethiopian economy. |
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Accepted: 23/09/2020 Published: 22/06/2020 |
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*Corresponding
Author Baye
Belay E-mail:
bayebelay@ gmail.com Phone:
251-0911 48 57 75 |
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Keywords: |
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INTRODUCTION
Like in many other sub-Saharan Africa
countries, agriculture in Ethiopia is a basis for the entire socioeconomic
structure of the country and has a major influence on all other economic
sectors and development processes and hence it plays a
crucial role in poverty reduction (Elias et al., 2013; GebreEyesus,
2015). Despite the marginal decline in its share of GDP in recent years, it is
still the single largest sector in terms of its contribution to GDP as
agricultural GDP constitutes 41% of total country's GDP (CSA, 2014/15).
As
to Gebru 2006 citing CSA 2003, out of the total production of agriculture,
about 70% comes from crop production.
According to Abegaz 2011, cereal crops constitute the largest share of
farming household’s production and consumption activities. Accordingly citing
Alemayehu et al., 2009, only five major cereals (barley, maize, sorghum,
teff and wheat) account for about 70% of area cultivated and 65% of output
produced. Fertilizer use is also concentrated on cereals followed by pulses and
oilseeds respectively according to Endale 2011 citing CSA 1995/96-2007/08. On
the other hand, according to Endale 2011, data from the Ethiopian Seed
Enterprise show that improved seeds are mostly used in wheat and maize
cultivation with an average of 89 and 42 thousand quintal in the period 1994/95
to 2005/06, respectively. Moreover, Abegaz 2011 citing the Household Income,
Consumption and Expenditure Survey of CSA indicated that the five major cereal
crops account for 46% of household’s total consumption. Therefore, a closer
look at what is happening in cereal production has an important welfare and
policy implication in Ethiopia (Abegaz, 2011).
According
to Ketema and Kassa 2016 citing Shiferaw et al. 2013, wheat contributes
about 20% of the total dietary calories and proteins worldwide. Ethiopia is the
second largest wheat producer in sub-Saharan Africa next to South Africa
(Nigussie et al., 2015). Mann and Warner 2017 citing Minot et al.
2015 indicated that there are approximately 4.7 million farmers growing wheat
on approximately 1.6 million hectares representing between 15 and 18% of total
crop area and less than 1% of all wheat production takes place outside the four
main regions of Ethiopia according to recent estimates. Wheat is one of the
major staple crops in the country in terms of both production and consumption
(Kelemu, 2017). According to Kelemu 2017 citing FAO 2014, it is the second most
important food in the country behind maize in terms of caloric intake.
The
Ethiopian agricultural sector, as to Gebru 2006 citing EEA 2004, is dominated
by small-scale farmers cultivating about 96% of the total area under crop,
producing more than 90% of total agricultural output and 97% of food crops.
With these statistics, one can easily infer to what extent the small-scale
farmers are the key element in strengthening the effort towards agricultural
growth and consequently to the overall economic growth (Gebre-Selassie &
Bekele).
On
the other hand, most smallholder farmers (i.e. 59% of total cultivated area)
reside in the moisture reliable cereal-based highlands among the five
agro-ecological regions of Ethiopia distinguished by agricultural researchers
(Taffesse et al., 2012). Accordingly, with farmers using virtually no
irrigation, reliable rainfall is an important condition to achieve good
agricultural productivity. In relation to this, as to the same source document,
the Meher rainfall season is overwhelmingly important as it contributes about
96.9% of total crop production and 95.5% of total cereal production in 2007/08.
With
respect to all these facts, it is not questionable that accelerated and
sustained growth in the country’s agriculture in general and in the crop
sub-sector in particular with special emphasis to the small-scale farmers will
greatly help to achieve the various goals of the country (Gebru, 2006; MoFED,
2003; Gebre-Selassie & Bekele).
Moreover,
food needs as well as the industrial demand for agricultural products increase
due to population growth (Bor and Bayaner, 2009). All these needs, according to
them, require an increase in the agricultural production. The growth in
agricultural production in sub-Saharan Africa in the past was achieved by expanding
the amount of land cultivated (Gebru, 2006). In relation with this, it is well
known that in our country there are regions where there are large populations
but limited land and vice versa (MoFED, 2003). Accordingly, most of the
lands available for settlement are found in the lowlands that lack basic
infrastructural facilities and pose serious health hazards. With little
suitable land available for expansion of crop cultivation, especially in the
highlands, future cereal production growth will need to come from increasing
land productivity mainly through the supply, duplication and diffusion of
continuously improving technology and information (Ayele et al. 2006
citing Reardon et al 1996; Taffesse et al. 2012; Elias et al.
2013; Matsumoto and Yamano, 2010).
Cognizant
of these as well as the fact that productivity is the major component of growth
and a fundamental requisite in many form of planning irrespective of the stage
of development and economic and social system as to Gebru 2006 citing Cheema 1978,
the national wheat research program has released and disseminated a number of
bread and durum wheat varieties since the 1950s and 1960s as to Ketema and
Kassa 2016 citing Tesfaye et al. 2001. According to the same source
citing CSA 2015b, a closer look at the proportion of the area covered by
improved varieties of different crops showed that wheat took the second rank
(7.4%) next to maize (46.4%) among cereals. Given the emphasis of increasing
crop production through higher fertilizer use, import of chemical fertilizer
augmented from 246,722 MT in 1995 to 375,717 MT in 2006 despite the removal of
fertilizer subsidies since 1997/98 according to Endale 2011 citing MOARD
2007/08. In this regard, according to Ketema and Kassa 2016 citing CSA 2015b,
wheat is the most fertilized crop (82%) among all crops and pesticide
application is also most common on wheat as compared to that on other cereal
crops.
Even
though crop productivity and production remained low and variable in the 90s
for the most part, there have been clear signs of change over the past decade
(Abate et al., 2015). According
to Kelemu 2017, the average level of wheat productivity for the period of
2000-2014 is about 1.73 ton/ha while the average growth rate in productivity is
about 5.93%. During the same period, total wheat production has been increasing
at 10.14% growth rate per annum (Kelemu, 2017).
As
to Tsusaka and Otsuka 2013 citing FAO 2011, although the production of staple
food has been increasing in sub-Saharan Africa, the rate of increase has not
been high enough to outstrip its high population growth rate as a result of
which per-capita agricultural production in the region has declined by about
10% since 1960. These all obviously calls for a further and a better growth in
agricultural productivity as well as quality with minimum adverse impact on the
environment. Kelemu 2017 citing Shiferaw and Okelo 2011 indicated that of the
cereals whose production is soon likely to exceed domestic demand requirements,
wheat is the commodity that will most easily find an export market to supply.
In view of this prospect, according to him, the need for increasing
productivity of wheat is very crucial.
Holistic
and appropriate evaluation of the efforts and corresponding results as well as
reasons/strengths and weaknesses/ of the past few decades in general and of the
past recent years in particular is necessary in order to create a more fertile
ground for the fast achievement of the aforementioned goal. In this regard, the
role of historical data collected by different agencies like CSA as well as of
different socio-economic studies carried out to provide vital policy and
related recommendations is indispensable. Studies that assess the contribution
of improved crop management practices information and technologies like
improved crop varieties for the productivity growth of such important and
widely cultivated cereals like wheat in Ethiopia in the past recent years are
among studies that can be cited in relation to this. However, studies carried
out in the country on this issue are not only few but also restricted to piece
meal or location specific approach. Besides, most studies were biased towards
those locations that had high/better suitability and/or preference for the
production of the specific crop considered. Thus, a nationally or regionally
representative data could not be collected for the studies and the conclusions
drawn so far would have low probability of influencing national and regional
policies. Moreover, the focus of most studies was measuring the impact of a
single improved agricultural technology or information rather than of a package
of agricultural technologies and information. Thus, the objective of this study
is to identify the impact of adoption of improved wheat technology package (including
improved wheat varieties, information regarding improved wheat management
practices as well as artificial/chemical fertilizer) on wheat productivity per
unit of land cropped in Oromia Regional State, Ethiopia.
MATERIALS
AND METHODS
Analytical
Framework for Evaluation of Adoption of Wheat Technology Package Impact on
Productivity
The correct evaluation of the impact of a
treatment like adoption of a technology package will require identifying the
“average treatment effect on the treated” defined as the difference in the
outcome variables between the treated objects like farmers and their
counterfactual. A counterfactual is defined as “knowledge of what would have
happened to those same people if they simultaneously had not received treatment”
(Olmos A., 2015 citing Shadish et al., 2002). In this context, as to
González et al. 2009, if Y represents the outcome variable and if
D is a dummy variable that takes the value of 1 if the individual was
treated and 0 otherwise, the “average treatment effect on the treated” will be
given by:
(1)
TATT= E[Y (1)
/ D =1]− E[Y (0) / D =1]
However, accordingly, given that the
counterfactual (E[Y (0) / D = 1]) is not observed, a proper substitute has to
be chosen to estimate TATT. Using the mean outcome of
non-beneficiaries-which is more likely observed in most of the cases-do not
solve the problem given that there is a possibility that the variables that
determine the treatment decision also affect the outcome variables. In this
case, the outcome of treated and non-treated individuals might differ leading
to selection bias (González et al., 2009). To clarify this idea, the
mean outcome of untreated individuals has to be added to (1) from which the
following expression can be easily derived:
(2) TATT={E[Y
(1) / D =1]− E[Y (0) / D =0]}−{E[Y
(0) / D =1]− E[Y (0) / D =0]}
Here E[Y (0) / D=
1]−E[Y (0) / D= 0] represents the selection bias
which will be equal to zero if treatment was given randomly which can be
achieved through the use of experimental approach.
The experimental
approach, according to Olmos A. 2015, has two characteristics: (1) it
manipulates the independent variable, that is, whether an individual receives
(or not) the intervention under scrutiny and (2) individuals are randomly
assigned to the independent variable. The first characteristic does not define
the experimental approach: most of the so-called quasi-experiments also
manipulate the independent variable. What defines the experimental method is
the use of random assignment (Olmos A., 2015). However, due to ethical or
logistical reasons, random assignment is not possible as to Olmos A. 2015
citing Bonell et al. 2009. Moreover, accordingly, equivalent groups are
not achieved despite the use of random assignment which is known as
randomization failure. Usual reasons why randomization can fail are associated
with missing data which happened in a systematic way and sometimes can go
undetected (Olmos A., 2015).
As a consequence of
randomization failure, or because of ethical or logistical reasons, in a very
large number of real-world interventions, experimental approaches are
impossible or very difficult to implement. However, if we are still interested
in demonstrating the causal link between our intervention and the observed
change, our options become limited. Some options include regression
discontinuity designs which can strengthen our confidence about causality by
selecting individuals to either the control or treatment condition based on a
cutoff score. Another alternative is propensity scores matching technique.
Propensity scores matching is a statistical technique that has proven useful to
evaluate treatment effects when using quasi-experimental or observational data
(Olmos A., 2015 citing Austin, 2011 and Rubin, 1983). Some of the benefits
associated with this technique, accordingly, are: (a) Creating adequate
counterfactuals when random assignment is infeasible or unethical, or when we
are interested in assessing treatment effects from survey, census
administrative, or other types of data, where we cannot assign individuals to
treatment conditions. (b) The development and use of propensity scores reduces
the number of covariates needed to control for external variables (thus
reducing its dimensionality) and increasing the chances of a match for every
individual in the treatment group. (c) The development of a propensity score is
associated with the selection model, not with the outcomes model, therefore the
adjustments are independent of the outcome. According to Olmos A. 2015,
propensity scores are defined as the conditional probability of assigning a
unit to a particular treatment condition (i.e., likelihood of receiving
treatment), given a set of observed covariates:
(z = i |X)
where z = treatment, i = treatment condition,
and X = covariates. In a two-group (treatment, control) experiment with random
assignment, the probability of each individual in the sample to be assigned to
the treatment condition is: (z = i│X)=0.5.
In a quasi-experiment, the probability (z = i│X) is unknown, but
it can be estimated from the data using a logistic regression model, where
treatment assignment is regressed on the set of observed covariates (the
so-called selection model). The propensity score then allows matching of
individuals in the control and treatment conditions with the same likelihood of
receiving treatment. Thus, a pair of participants (one in the treatment, one in
the control group) sharing a similar propensity score are seen as equal, even
though they may differ on the specific values of the covariates (Olmos A. 2015
citing Holmes 2014).
Data and Variables
The data
utilized for this study is acquired from farm household survey undertaken
during 2015/16 by Ethiopian Institute of Agricultural Research (EIAR) in
collaboration with the International Maize and Wheat Improvement Center
(CIMMYT). A total of 837 farm households living in major wheat producing areas
of 11administrative zones (provinces), 27districts and 65 “kebeles”/villages/local
councils in Oromia Regional State were interviewed. A multi-stage stratified
sampling procedure was used to select villages from each agro-ecology, and
households from each “kebele”/village. First, agro-ecological zones that
account for at least 3% of the national wheat area were selected from the major
wheat growing areas of Oromia Regional State, Ethiopia. Second, based on
proportionate random sampling, up to 21 villages in each agro-ecology, and 15
to 18 farm households in each village were randomly selected. The data was
collected using a pre-tested interview schedule by trained and experienced
enumerators who speak the local language and have good knowledge of the farming
systems. Moreover, the data collection process was supervised by experienced
researchers to ensure the quality of the data.
Productivity
stands for the productivity of wheat per unit of land cropped measured in
kilogram per hectare.
LnProductivity stands for the natural
logarithmic transformation of Productivity.
HHAGE stands for the age of a household head.
HHSEX is a dummy variable indicating the sex
of a household head where HHSEX = 1 if the head is male and 0 if otherwise.
FAMILY_SIZE stands for size of a household.
HHEDU is a dummy variable indicating whether
a household head is literate where HHEDU = 1 if the head is literate/able to
read and write/ and 0 if otherwise.
CREDIT is a dummy variable indicating
household's access to credit where CREDIT = 1 if the household has got the
credit it needed in 2013 and 0 if otherwise.
LANDHOLDING_SIZE stands for size of the land
holding of a household measured in hectare.
DSTMNMKT stands for distance to the nearest
main market from residence measured in kilometer.
OXEN stands for the total number of oxen
owned by a household.
TNOTRAREDS stands for the total number of
traders known by a household who could buy the produced grain.
EXCONTACT is a dummy variable indicating
whether a household had contact with government extension workers where
EXCONTACT = 1 if the household had got contact with government extension
workers and 0 if otherwise.
RESULTS
AND DISCUSSIONS
Descriptive
Statistics
Various
variables that were included in the propensity score matching model that
describe the major observed characteristics of the sample respondents are
presented in table 1. While the average rate of growth in productivity of full
and partial adopters of modern technologies & information is 7.4% and 6.96%
respectively, that of non-adopters of modern technologies & information is only
6.6%. Thus, it tentatively shows that there is significant difference in
productivity growth rate between these two pairs of groups of households. Some
of the most important demographic determinants that influence adoption of a
technology include family size, level of education and age. There exists a
significant difference between adopters and non-adopters of wheat technology
and information in terms of these demographic factors as depicted by the
descriptive statistics. Male-headed households were found to be more probable
in adopting improved wheat technology package fully which is in line with the
fact that female-headed households are endowed with less resource and are less
exposed to new information and ideas according to Admassie and Ayele 2004. Besides,
the descriptive statistics show that literate-headed household are more
probable in adopting improved wheat technology package fully and partially.
This might be because education may make farmers more receptive to advice from
an extension agent or more able to deal with technical recommendations that
require a certain level of numeracy or literacy (Admassie and Ayele, 2004). On
the other hand, households with relatively larger family size are less likely
to adopt improved wheat technology package fully and partially which is a bit
contradictory to the fact that such households, on one hand, do not face labor
shortage that may be needed to manage the increased output which resulted from
technology and information adoption and, on the other hand, higher family size
necessitates increased productivity to feed the family. Farmers with relatively
smaller land holding size tend to adopt improved wheat technology package fully
which is in line with the fact that certain technologies may be appropriate for
the intensive management characteristic of smaller farms as to Admassie and
Ayele 2004. Farmers with relatively larger oxen ownership tend to adopt
improved wheat technology package fully as expected. Moreover, those farmers
who had contact with government extension workers are more likely to adopt
improved wheat technology package fully and partially than those that had not.
Table 1(a): Descriptive statistics of important variables
used in the probit model-Propensity
score matching
|
Variables |
Unit |
Full Adopters of
Modern Technologies & Information Mean(se) |
Non-Adopters of
Modern Technologies & Information Mean(se) |
Aggregate Mean(se) |
t-stat. |
|
Outcome variable |
|
|
|
|
|
|
Productivity |
# |
1935.06(41.86) |
931.48(214.35) |
1921.58(41.63) |
-2.79*** |
|
LnProductivity |
% |
7.41(0.
0231) |
6.605(0.2477) |
7.398(0.0233) |
-4.02*** |
|
Variables that affect probability of
adoption |
|
|
|
|
|
|
HHAGE |
# |
45.17(0.4836) |
49.89(6.25) |
45.23(0.484) |
1.12 |
|
HHSEX
(Male=1) |
1=Yes |
0.917(0.01077) |
0.78(0.147) |
0.915(0.0108) |
-1.48* |
|
FAMILY_SIZE |
# |
7.17(0.0915) |
8.33(0.93) |
7.18(0.0912) |
1.47* |
|
HHEDU (Read & write=1) |
1=yes |
0.705(0.01775) |
0.33(0.17) |
0.7(0.01772) |
-2.42*** |
|
CREDIT |
1=yes |
0.0348(0.0071) |
0(0) |
0.0343(0.007) |
-0.57 |
|
LANDHOLDING_SIZE |
ha |
1.895(0.0577) |
2.7(0.903) |
1.905(0.0582) |
1.596* |
|
DSTMNMKT |
km |
10.344(0.255) |
9.78(0.662) |
10.336(0.251) |
-0.259 |
|
OXEN |
# |
2.72(0.0734) |
1.67(0.24) |
2.71(0.0726) |
-1.676** |
|
TNOTRAREDS |
# |
4.62(0.206) |
3.33(1.01) |
4.6(0.204) |
-0.728 |
|
EXCONTACT |
1=yes |
0.89(0.012) |
0(0) |
0.87(0.013) |
-8.37*** |
***,
**, * indicate significance at 1 percent, 5 percent and 10 percent level
respectively.
Source: Own
computation, 2019
Table 1(b): Descriptive statistics of important variables
used in the probit model-Propensity
score matching
|
Variables |
Unit |
Partial Adopters of
Modern Technologies & Information Mean(se) |
Non-Adopters of Modern
Technologies & Information Mean(se) |
Aggregate Mean(se) |
t-stat. |
|
Outcome variable |
|
|
|
|
|
|
Productivity |
# |
1286.03(63.64) |
931.48(214.35) |
1267.90(61.54) |
-1.27 |
|
LnProductivity |
% |
6.96
(0.05) |
6.605(0.248) |
6.94(0.0496) |
-1.58* |
|
Variables that affect probability of
adoption |
|
|
|
|
|
|
HHAGE |
# |
46.43(1.108) |
49.89(6.25) |
46.60(1.095) |
0.696 |
|
HHSEX
(Male=1) |
1=Yes |
0.892(0.0241) |
0.78(0.147) |
0.886(0.02399) |
-1.05 |
|
FAMILY_SIZE |
# |
6.95(0.179) |
8.33(0.93) |
7.02(0.178) |
1.73** |
|
HHEDU (Read & write=1) |
1=yes |
0.617(0.0377) |
0.33(0.167) |
0.602(0.036997) |
-1.697** |
|
CREDIT |
1=yes |
0.024(0.0119) |
0(0) |
0.023(0.0113) |
-0.467 |
|
LANDHOLDING_SIZE |
ha |
2.03(0.128) |
2.7(0.903) |
2.06(0.129) |
1.145 |
|
DSTMNMKT |
km |
10.64(0.431) |
9.78(0.662) |
10.599(0.411) |
-0.463 |
|
OXEN |
# |
2.08(0.114) |
1.67(0.236) |
2.06(0.109) |
-0.84 |
|
TNOTRAREDS |
# |
3.87(0.312) |
3.33(1.014) |
3.84(0.2999) |
-0.39 |
|
EXCONTACT |
1=yes |
0.563(0.0385) |
0(0) |
0.534(0.0377) |
-3.38*** |
***,
**, * indicate significance at 1 percent, 5 percent and 10 percent level
respectively.
Source: Own computation, 2019
Propensity
Scores Estimation using Probit Model
The
descriptive statistics of the key variables affecting adoption of improved wheat technology
package has shown a tentative impact of
improved wheat technology package
adoption on increasing productivity. Nevertheless, a mere comparison of
productivity has no causal meaning since improved wheat technology
package adoption is endogenous. And it
is difficult to attribute the change to adoption of improved wheat
technology package since the difference
in productivity might be owing to other determinants. To this end, a rigorous
impact evaluation method; namely, Propensity Score Matching has to be employed
to control for observed characteristics and determine the actual attributable
impact of improved wheat technology package adoption on productivity in wheat producing areas of Oromia Regional
State, Ethiopia. Propensity scores for full adopters and non-adopters as well
as for partial adopters and non-adopters were estimated using a probit model to
compare the treatment group with the control group. In this regard, only those
variables that significantly affect probability of full and partial improved
wheat technology package adoption were
used in estimating the propensity scores. The test for ‘balancing condition’
across the treatment and control groups was done and the result as indicated on
figure 1 proved that the balancing condition is satisfied.
Each
observation’s propensity scores are calculated using a probit model. The
propensity score for full adopters ranges between 0.5393064 and 0. 998062 while
it ranges between 0.496226 and 0.9631822 for non-adopters. And the region of
common support for the distribution of estimated propensity scores of full
adopters and non-adopters ranges between 0.53930637 and 0.99806198. When
matching techniques are employed, observations whose propensity score lies
outside this range were discarded. The visual presentation of the distributions
of the propensity scores is plotted in figure 1(a). The common support
condition is satisfied as indicated by the density distributions of the
estimated propensity scores for the treatment and control groups as there is
substantial overlap in the distribution of the propensity scores of both full
adopters and non-adopters. On the other hand, the propensity score for partial
adopters ranges between 0.5616269 and
0.9974838 while it ranges between 0.6139216 and 0.9680441 for non-adopters. And
the region of common support for the distribution of estimated propensity
scores of partial adopters and non-adopters ranges between 0.56162689 and
0.9974838. When matching techniques are employed, observations whose propensity
score lies outside this range were discarded. The visual presentation of the
distributions of the propensity scores is plotted in figure 1(b). The common support
condition is satisfied as indicated by the density distributions of the
estimated propensity scores for the treatment and control groups as there is
substantial overlap in the distribution of the propensity scores of both
partial adopters and non-adopters.

Figure 1(a):
Distribution of propensity scores of full adopters and non-adopters

Figure 1(b):
Distribution of propensity scores of partial adopters and non-adopters
Assessing Matching Quality
Ensuring good balance between treated and control group is the most
important step in using any propensity score
method. The before
and after matching covariate balancing tests presented on table 2 suggested
that the proposed specification of the propensity score is fairly successful in
balancing the distribution of covariates between the two groups as indicated by
decreasing pseudo R2, decreasing
mean standardized bias and the insignificant p-values of the likelihood ratio
test.
Table
2(a): Propensity score matching quality test
|
Sample |
Ps R2 |
LR chi2 |
p>chi2 |
Meanbias |
Medbias |
R |
%Var |
|
Unmatched |
0.176 |
10.09 |
0.073 |
106.9 |
55.7 |
1.12 |
100 |
|
Matched |
0.161 |
33.44 |
0.000 |
38.2 |
33.7 |
2.51* |
100 |
*
if B>25%, R outside [0.5; 2]
Table
2(b): Propensity score matching quality test
|
Sample |
Ps R2 |
LR chi2 |
p>chi2 |
Meanbias |
Medbias |
R |
%Var |
|
Unmatched |
0.133 |
7.54 |
0.023 |
87.6 |
57.4 |
1.17 |
100 |
|
Matched |
0.098 |
19.83 |
0.000 |
45.9 |
65.6 |
0.94 |
100 |
*
if B>25%, R outside [0.5; 2]
Average treatment effects estimation
Different impact
estimators were employed to get estimated treatment effect that disclosed full
as well as partial adoption of improved wheat technology package has a positive and significant impact on
productivity growth. Table 3 depicts the average impact of improved
wheat technology package adoption on
productivity growth following nearest neighbor matching (NNM), Stratification
Matching, Radius (Caliper) Matching and Kernel Matching (KM) techniques.
Accordingly, most of the matching techniques revealed that on the average full adopters
of improved wheat technology package get a significantly higher rate of growth in productivity, ranging from
61 to 67%, than their counterparts, the non-adopters. Moreover, half of the
matching techniques revealed that on the average partial adopters of improved
wheat technology package get a significantly
higher rate of growth in productivity, ranging from 38 to 40%, than their
counterparts, the non-adopters. However,
the growth rate of full package adopters that includes improved wheat
varieties, information regarding improved wheat management practices as well as
artificial/chemical fertilizer is
clearly higher than that of the partial package adopters.
Table
3(a): Average treatment effects estimation using different propensity score
matching estimators
|
Outcome variable |
Matching algorithm |
Mean of outcome variable based on matched observations |
ATT |
t-stat. |
|
|
Full
Adopters |
Non-Adopters |
||||
|
LnProductivity |
Nearest neighbor matching |
7.23 |
6.61 |
0.614 |
1.841** |
|
Stratification
matching |
|
|
0.669 |
2.043** |
|
|
Caliper matching |
7.42 |
6.56 |
0.861 |
1.674 |
|
|
Kernel matching |
7.23 |
6.58 |
0.646 |
2.916*** |
|
***, **, * indicate significance at 1
percent, 5 percent and 10 percent level respectively.
Bootstrapped standard errors are based on 100
replications.
Source:
Own computation, 2019
Table
3(b): Average treatment effects estimation using different propensity score
matching estimators
|
Outcome variable |
Matching algorithm |
Mean of outcome variable based on matched observations |
ATT |
t-stat. |
|
|
Partial Adopters |
Non-Adopters |
||||
|
LnProductivity |
Nearest neighbor matching |
6.95 |
6.69 |
0.268 |
0.612 |
|
Stratification
matching |
|
|
0.380 |
1.484* |
|
|
Caliper matching |
6.82 |
6.59 |
0.226 |
0.677 |
|
|
Kernel matching |
6.95 |
6.56 |
0.398 |
1.916** |
|
**, * indicate significance at 5 percent and
10 percent level respectively.
Bootstrapped standard errors are based on 100
replications.
Source:
Own computation, 2019
CONCLUSION AND RECOMMENDATION
This study is undertaken to identify the
impact of adoption of improved wheat technology package that includes improved wheat varieties,
information regarding improved wheat management practices as well as
artificial/chemical fertilizer on wheat productivity in Oromia Regional State, Ethiopia.
It used propensity score matching technique which is a robust impact evaluation
technique that identifies the impact which can be attributed to improved wheat
technology package adoption. The study also employed and compared various
matching algorithms to ensure robustness of the impact estimates. Finally, the
study concludes that adoption of improved wheat technology package enabled farm
households that adopted it fully to enjoy a relatively higher and significantly
positive productivity than their counterparts, the non-adopters as well as the partial adopters. This
indicates that full adoption of improved wheat technology package has a huge potential
in strengthening the Region’s agricultural extension system that targets
increasing production and productivity. Therefore, this study recommends to
widely scale-up full package of improved wheat varieties and information as well
as other appropriate modern agricultural technologies and information to all
wheat producing farm households, and this should be accompanied by increasing
availability of affordable improved wheat agricultural technologies and
information for the smallholder farmers to enhance their livelihood which
obviously calls for the well-coordinated, effective as well as efficient effort
of all of the relevant stakeholders of the agricultural sector of the Region.
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Cite this Article: Belay, B (2020). Impact of Improved Wheat
Technology Package Adoption on Productivity in Oromia Regional State,
Ethiopia. Greener
Journal of Agricultural Sciences 10(2): 103-113. . |