(2015) Planting the seeds: The impact of training on mango producers in Haiti
Summary — This paper evaluates the short-term impacts of a development project aimed at increasing mango yields, sales, and income for small mango farmers in rural Haiti. The study uses matching methods and difference-in-difference to address selection bias and assess the project's impact on adoption of improved practices and sales.
Key Findings
- The project significantly increased the planting of Francique mango trees.
- The project had a positive impact on the adoption of improved agricultural practices (pruning, tidying, grafting, and fencing).
- The project has significant effects on the adoption of preferred commercialization channels, helping farmers shift from selling to middlemen to selling to producer business groups (PBGs).
- The adoption of improved production practices and preferred marketing channels has not yet translated into increases in production or sales.
- The results are robust to the presence of other similar programs in the project areas.
Full Description
This paper evaluates the short-term impacts of a development project designed to increase mango yields, sales of mango products, and the income of small mango farmers in rural Haiti. The evaluation uses data from a baseline survey in 2012 and a follow-up survey in 2013, focusing on short-term outcomes such as the adoption of preferred mango varieties, improved production and harvest practices, and behavioral changes in farmers’ production and commercialization decisions. Various matching methods, in combination with difference-in-difference (DID), are used to deal with potential selection bias. The results show that the project increased the number of young Francique trees planted and encouraged the adoption of best practices, but has not yet led to a noticeable increase in total sales.
Full Document Text
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Planting the seeds:
The impact of training on mango producers in
Haiti
Irani Arráiz
Carla Calero
Songqing Jin
Alexandra Peralta
IDB WORKING PAPER SERIES Nº IDB-WP-610
August 2015
Multilateral Investment Fund
Inter-American Development Bank
August 2015
Planting the seeds:
The impact of training on mango producers in Haiti
Irani Arráiz
Carla Calero
Songqing Jin
Alexandra Peralta
Cataloging-in-Publication data provided by the
Inter-American Development Bank
Felipe Herrera Library
Planting the seeds: the impact of training on mango producers in Haiti / Irani Arráiz,
Carla Calero, Songqing Jin, Alexandra Peralta.
p. cm. — (IDB Working Paper Series ; 610)
Includes bibliographic references.
1. Agricultural development projects—Evaluation—Haiti. 2. Occupational training—
Evaluation—Haiti. 3. Agricultural productivity—Evaluation—Haiti. I. Arráiz, Irani. II.
Calero, Carla. III. Jin, Songqing. IV. Peralta, Alexandra. V. Inter-American
Development Bank. Office of the Multilateral Investment Fund. VI. Series.
IDB-WP-610
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http://www.iadb.org
2015
Planting the seeds: The impact of training on mango producers
in Haiti
Irani Arraiz
y
, Carla Calero
z
, Songqing Jin
x
, and Alexandra Peralta
{
August 2015
Abstract
This paper evaluates the short-term impacts of a development project that aims to
increase mango yields, sales of mango products, and the income of small mango farmers
in rural Haiti. Various matching methods, in combination with dierence-in-dierence
(DID), are used to deal with the potential selection bias associated with nonrandom treat-
ment assignment. Robustness checks are conducted to investigate whether and to what
extent the results are aected by the coexistence of other similar projects in the same
sites. Rosenbaum bounds analysis is carried out to check the sensitivity of the estimated
impacts|based on matching methods|to deviations from the conditional independence
assumptions; the relative importance of unobserved factors in the decision to participate.
Our results show that in a 16-month period, the project increased the number of young
Franciquetrees planted|a type that has greater market and export potential than tra-
ditional mango varieties|and likely encouraged the adoption of best practices. But the
project has not yet led to a noticeable increase in total sales. The adoption of improved
production practices is too recent to translate into signicant changes in production and
sales. While the robustness check suggests that the results are not caused by the presence
of other similar programs on the same sites, the Rosenbaum bounds sensitivity analysis
suggests that the matching results are robust against potential \hidden bias" arising from
unobserved outcome variables in some but not all cases.
JEL Classication:Q13, Q16, O12.
Keywords:Agriculture, impact evaluation, producer cooperative, extension services,
Haiti, mango.
This study was coordinated and nanced by the Multilateral Investment Fund (MIF) of the Inter-American
Development Bank (IDB). The authors are grateful to Technoserve for its support in conducting the study.
The opinions expressed in this publication are those of the authors and do not necessarily reect the views of
the Inter-American Development Bank, its Board of Directors, or the countries they represent.
y
Inter-American Development Bank. E-mail: iarraiz@iadb.org
z
Inter-American Development Bank. E-mail: ccalero@iadb.org
x
Department of Agricultural, Food and Resource Economics, Michigan State University. E-mail:
jins@anr.msu.edu
{
Global Food Studies, the University of Adelaide. Email: alexandra.peralta@adelaide.edu.au
1 Introduction
The importance of adopting relevant technologies to reduce poverty and spur economic deve-
lopment has long been emphasized by development economists and agricultural practitioners
(Feder et al.,;,). The adoption of high-yield varieties (HYVs) and
complementary modern inputs and crop management practices during the Asia Green Revo-
lution is widely acclaimed as one of the most successful stories in the economic development
of South and Southeast Asia (Evenson and Gollin;,;
et al.,;,). Meanwhile, the low adoption rate of HYVs, fertilizers, irriga-
tion technologies, and other agricultural and resource management practices is cited as a key
reason for the mostly unsatisfactory performance of the agricultural sector in Sub-Saharan
Africa (,;,;,;
and Kijima,;,). In Latin America and the Caribbean (LAC)
considerable advances have been made in the development of HYVs, agricultural mechaniza-
tion, and agricultural practices; but economic inequality remains high, and many rural areas
still lag behind urban areas (World Bank,).
Despite the existence of many proven technologies and improved agricultural and resource
management practices, the adoption of such technologies and practices by smallholder farmers
is generally low in developing countries (,;,;
World Bank,). Early studies on technology adoption identify several key obstacles faced
by small farmers who might otherwise adopt new technologies: lack of credit, limited access
to information, aversion to risk, inadequate farm size, insecure land tenure, a low level of
human capital, and poor infrastructure (Feder et al.,;,). For the
past decade or so, international organizations (both in and outside government) have done
much to encourage farmers to adopt new technologies and agricultural best practices through
agricultural development projects. A common feature of such development projects is that
they typically aim to overcome multiple constraints and to promote the adoption of multi-
ple practices and behavior changes. Another important feature is that project locations and
beneciaries are typically not randomly assigned. Though these features pose considerable
methodological challenges to any study of project impacts, many researchers have compiled
impact evaluations of agricultural development projects in the past ten years or so (Dil-
lon,;,;,;,;
and Barrett,;,;,). Yet the research|
especially that using rigorous evaluation methods|is disproportionately small relative to the
large number of projects implemented (IDB,;,). In addition, few
studies evaluate the possible short-term impactsincluding the adoption of particular agricul-
tural technologies or changes in behavior|or intermediate impacts of projects before their
closure (Pamuk et al.,;,). Such impacts are important, signaling future
project success and indicating necessary corrections in strategy.
To add to this emerging literature, we evaluate the short-term impact of a development
project that aims to increase the income of small mango producers in Haiti. Our evaluation
is based on data from a baseline survey and a follow-up survey after 16 months of project
implementation. Because of the short time period involved, we focus on evaluating a set of
short-term outcomes, such as the adoption of a preferred mango variety, improved production
and harvest practices, and behavioral changes in farmers' production and commercialization
decisions. Longer-term outcomes such as increases in mango production and sales take longer
to materialize due to the life cycle of the mango tree. For example, it takes more than a year
1
for mango trees to mature and become productive (University of Hawai Manoa,).
As with many other agricultural development projects, the main empirical challenge to
an evaluation of the project is the fact that project beneciaries were not randomly assigned.
Direct comparison of outcomes between project participants and nonparticipants would lead
to a biased estimation of the projects impacts. To control for the potential selection bias, we
use nonexperimental econometric methods: matching, and a combination of matching and
dierence-in-dierence (DID) methods.
Due to dierences in survey instruments between baseline and follow-up, we are forced to
adopt dierent evaluation methods for dierent outcome variables. Panel data are available
only for some outcome variables. For other outcome variables, we have data from only the
follow-up survey. In particular, we use propensity score matching (PSM) and matching in
covariates for the outcomes for which only follow-up survey data are available. In order to
assess how robust our matching estimates are to possible hidden bias|caused by the eect
of unobserved variables that simultaneously aect assignment to treatment and the outcome
variable|we use the Rosenbaum bounds approach. For the outcomes for which we have panel
data from both the baseline and follow-up surveys, we estimate the impacts using dierence-in-
dierence, propensity score matching (DID-PSM), and DID-matching in covariates to control
for time invariant unobserved heterogeneity.
There is also a concern that the presence of other projects with similar characteristics
in the project intervention sites could potentially bias our evaluation results. To investigate
whether and to what extent the presence of other projects bias our results, we conduct a
robustness check by excluding all the observations (in both treatment and control groups) of
parties that participated in other projects.
1
The results suggest that the project signicantly increased the planting ofFranciquemango
trees (the variety preferred for export), but that these trees are still too young to bear fruit
(that is, they are not yet productive) and so have not translated into increases in yields or sales.
The project also had a positive impact on the adoption of improved agricultural practices
(pruning, tidying, grafting, and fencing), and on preferred commercialization behaviors (with
a shift away from selling to middlemen and toward selling to producer business groups [PBGs],
or cells). But the results on the adoption of improved practices should be interpreted with
caution, since they are sensitive to possible deviations from the identifying unconfoundedness
assumption. Finally, our robustness checks suggest that the presence of other projects did
not inuence the estimated impacts of the project.
The rest of the paper is organized as follows. Section 2 describes the project, focusing
on the theory of change and the selection of project beneciaries. Section 3 presents the
data and the sample design, and Section 4 proposes dierent evaluation methods. Section
5 discusses the main impact evaluation results, the robustness checks, and the sensitivity
analysis, followed by conclusions and recommendations in Section 6.
1
Without more detailed data on the nature and distribution of other programs between the treatment and
control groups, it is not possible to know whether they would bias our results. The robustness checks indirectly
assess whether and to what degree the presence of other programs would bias the main results.
2
2 The Project
2.1 Background
Haiti is the poorest country in Latin America and one of the poorest in the world. Conditions
in the country worsened after it was hit by a 7.0 magnitude earthquake in 2010. Its gross
national income (GNI) per capita was $760 in 2012. Eighty percent of its population earn less
than $2 per day, and 50 percent live below the poverty line ($1 per day) (World Bank,).
More than 60 percent of Haiti's population depends on agriculture for their livelihood. The
country also relies heavily on remittances from the Haitian diaspora and on foreign aid.
Haiti's economy has been slowly recovering since 2010, with most of the economic growth
coming from agricultural production, construction, and the garment sector (World Bank,
2014).
The poverty seen in Haiti is typical of poor rural areas in developing countries, where
agriculture plays a major role in the strategy for increasing agricultural incomes and household
wealth (World Bank, 2008). Mangoes are among Haitis main agricultural products, with a
high potential for exportation. The country is among the 20 largest mango producers in
the world (FAO,). But several constraints|such as inadequate production technologies
for commercial mangos, institutional barriers, and inadequate (or lacking) infrastructure|
impede the increase of mango production and exports (Casta~neda et al.,).
There are about 100 mango varieties planted in Haiti, but onlyFranciqueis exported.
Of total production, only between 2.5 and 5.0 percent reach the export market (FAO,).
Most exported Haitian mangoes go to the United States. Low-quality yields and damage or
spoilage during transportation are among the main reasons for the low export rates of Haitian
mangoes. Haiti's mango producers are predominately smallholder farmers who own 10 trees
or less and lack the technical knowledge to produce mangoes of export standards (Casta~neda
et al.,).
In addition, farmers usually sell mangoes to middlemen, who are responsible for the harvest
and transport of mature mangoes. Farmers lack the knowledge, experience, and technical skills
required to perform these activities themselves. Mangoes are usually sold per tree and not
by the quantity of actual mangoes produced. Farmers' lack of access to credit to smooth
consumption often leads to the premature sale of mangoes to middlemen, who oer cash in
advance.
2.2 The Project
The project was launched in 2010 to overcome the production and commercialization cons-
traints faced by small mango farmers in Haiti. The aim of the project was to increase the
income of smallholder farmers and facilitate their access to the value chain for mango exports.
The project promotes the formation of producer business groups (PBGs), or cells. Members
of PBGs are trained in good practices in mango production|both harvest and postharvest|
and commercialization, and basic business literacy (see Table 1 for a detailed list of project
interventions). The project promotes the planting of theFranciquemango variety, which
is in high demand among potential commercial buyers and has the highest export potential
(Casta~neda et al.,). Participants are expected to adopt the practices promoted by the
project.
The project is a value chain development project implemented in Haiti by TechnoServe,
a nonprot organization with worldwide experience, with the support of project partners.
3
2.2.1The Project's Theory of Change
The project seeks to boost farmers' income through higher mango yields, higher-quality man-
goes that adhere to international standards, as well as a better linking of producers to inter-
national mango value chains. This combination of eects (increased productivity, improved
quality, and commercial linkages) is expected to generate an increase in mango sales and the
development of stable commercial relationships between farmers and reliable exporters. Ex-
porters, meanwhile, would benet from a higher-quality and more-predictable mango supply.
To achieve the project's objectives, TechnoServe provides training to local mango producers
and connects smallholder producers to exporters via PBGs. In addition to establishing PBGs,
the project engages existing farmer cooperatives.
According to the project design, producers will see increases in mango sales through a
combination of three eects: (i) an increase in mango production, either through an increase
in the yield of trees already bearing fruit or through new trees; (ii) a reduction of waste due to
better harvest and postharvest practices (unnecessary losses are estimated to aect up to 50
percent of mango production); and (iii) an increase in the price producers are able to obtain
in the market, as they begin selling higher-quality mangoes through appropriate channels.
In the context of the PBGs set up by the project, TechnoServe provides farmers with
training in pruning and tree care, nursery care, and orchard-related extension services.
2;3
The
assumption is that by pruning trees farmers maintain their health, productivity, and size|
and facilitate better harvests and improved fruit quality. The program also seeks to increase
volume by planting new saplings and, in 2013, TechnoServe decided to undertake grafting to
achieve early increases in mango volumes. Thus, increases in volume are to be achieved via
(i) increases in the productivity of existing, producing trees (via practices such as pruning
and grafting), and (ii) the production of new trees (from saplings).
To reduce mango waste, TechnoServe provides farmers with training in harvest and posthar-
vest best practices and in the utilization of local transportation.
4
The assumption is that by
properly selecting the harvest period that will maximize mango quality, using the right har-
vest tools to reduce spoilage, and properly handling the harvested mangoes and sorting them
according to the corresponding sales channels to maximize prices per channel, farmers can
reduce losses|which before the project were as high as 50 percent of the total potential
harvest.
5
2
Asrey et al.2013] nd that pruning results in signicantly higher fruit weight, fruit rmness, total
carotenoids, antioxidant capacity, and total phenolic content. Early maturity of fruits is observed from un-
pruned trees with faster color change, higher total soluble solids, and lower titratable acidity. The fruits
harvested from pruned trees show signs of slower ripening, and lower respiration, ethylene evolution rates, and
enzyme activity when compared with fruits from unpruned trees. Both anthracnose and stem-end rot disease
percentages are reduced in ripe fruits from pruned trees.
3
The pruning and tree care training module teaches farmers to identify and cut appropriate tree branches and
maintain mango tree canopy to maximize fruit quality (targeted to all farmers); the nursery training module
teaches farmers the process of cultivating a mango from a seedling, including protection against common
problems and building seed stock (targeted to a selection of farmers). Farmers also receive on site visits from
technicians to help them rehabilitate their mango orchards (extension services).
4
The harvest and postharvest training module teaches farmers to identify appropriate harvest periods and
methods, and to properly sort mangoes according to corresponding sales channels. The local transportation
training module teaches farmers the appropriate way to transport their mangoes to the appropriate collection
center (both modules target all farmers).
5
Casta~neda et al.2010, p. 8] explain that when farmers presell their fruit to middlemen on farms, the
middlemen harvest all fruits from a given tree, whether they are adequately ripe or not:
After picking all fruit, middlemen select and leave rejected fruits at the farm, paying only for the
4
To increase the price that farmers can get for their mangoes, TechnoServe provides farmers
with training in the creation of PBGs and in business planning.
6
The assumption is that by
selling their production appropriately (by dozens instead of by plot or tree, for example)
and using the PBGs as channels (rather than negotiating by themselves), farmers can get an
overall better price for their harvest.
Some of these actions may have immediate eects: for example, the adoption of harvest and
postharvest best practices could immediately increase mango sales by improving the quality
of the fruit and reducing spoilage during transportation. This is the eort with potentially
the highest immediate impact. Other activities supported by the program and related to
harvesting could also have immediate eects: better access to credit could potentially increase
the quality of mangoes sold, by limiting the need of farmers to sell their mangoes before the
appropriate time.
Another action that could have immediate eects is the adoption of commercialization best
practices: markets for agricultural products are becoming more integrated and concentrated
in their structure, and smallholder farmers tend to be excluded from the modern value chain,
mainly because of the challenges of complying with quality standards and of providing the
quantities required to ensure reliability (Barrett,;,;). Or-
ganizing farmers in groups reduces risk and transaction costs, and increases information ows
(IFAD,). It also increases the farmers' bargaining power for better contract conditions,
and ensures reliable quality and quantities of product (Markelova et al.,).
The third action|the adoption of agricultural best practices (pruning and tree care)
and the planting of newFranciquetrees and grafting of productive, non-Franciquetrees|is
unlikely to generate results in the short run. In fact, the pruning promoted by the program,
for example, could negatively aect mango yield in the short run.2006] states
that severe pruning (done to rejuvenate mango trees so large that the canopy migrates far
beyond the reach of harvesters) accompanied by tip pruning (to reduce the ush frequency
back to normal) would eliminate owering and reduce production for about a year.
et al.2013] designed an experiment to quantify the eects of pruning done to manage canopy
size. The fruit yield of pruned trees was found to decrease in the rst year compared with
the fruit yield of unpruned trees; it increased beyond unpruned trees during the second year.
In another experiment,2013] nd that the initiation of fruiting begins after
the third year of pruning. Meanwhile, it is too early for newFranciquetrees and grafted,
productive, non-Franciquetrees to bear fruit|it takes 5{6 years for a new tree or 3{4 years
for a grafted tree to start bearing fruit.
There are other reasons to believe that the project initiatives undertaken thus far will
not yield immediate results. It is well known that it takes time to translate adoption into
chosen mangoes. Rejected fruits could be immature, over ripe, bruised or y infested, with a low
chance of commercialization. Mango losses may reach up to 50 percent of the total potential har-
vest. Mango is sold to exporters in Port-au-Prince (transportation is arranged with the exporter,
and prices vary), however, at the export facilities, it is necessary to re-classify mangoes due to
the inappropriate postharvest practices of middlemen (rejects account for around 50 percent).
Rejected mangoes are sold to madam sarahs.
\Madam sarahs" are retailers, usually women, who sell the mangoes in the local markets.
6
The producer business group (PBG) training module supports farmers in creating and organizing PBGs,
which function as intermediaries for smallholder farmers to increase their access to markets (and improve their
negotiating power in bulk sale, transportation, specialization of tasks, and so on). In the business planning
training module, farmers learn about the sales channels available to smallholder farmers, and the components
of a business and marketing plan. Both modules target all farmers.
5
changes in production, sales, and income. As farmers decide which practices to adopt, they
must consider risk, protability, and input constraints (Feder et al.,;,
2008). Technology adoption involves a process of learning over time (Foster and Rosenzweig,
1996). And nally, farmers adopt new technologies in a stepwise fashion, not all at once
(Byerlee and Hesse de Polanco,), even when such practices are promoted as a package.
2.2.2Targeting of Beneciaries
The key challenge we face in our evaluation analysis is the fact that the project areas and
project beneciaries were not randomly assigned. PBGs were established in areas of high po-
tential mango yield, as indicated by the quality and volume of current production, agronomic
characteristics, local industry players, land availability, and infrastructure. Farmers eligible
to participate in the program grow mangoes, have at least ve trees, and farm between 0.5
and 5 hectares of land; they are also required to be members of cooperatives and to live in
the communes targeted by the project. But these eligibility criteria have not been strictly
enforced; they have instead served as a guide for selecting poor, smallholder farmers as project
beneciaries.
Within selected communes, community members were hired by TechnoServe and assigned
to recruit farmers. Their recruitment areas were determined by their location and their ease
of access to surrounding areas where mango producers were likely to be found. The project
species that recruiters can travel for a maximum of an hour-and-a-half by foot to promote
the project among mango producers and to invite them to join a local rally where they may
enroll in the project. The decision to join the project or not is voluntary.
Given the way beneciary communes and farmers were selected, two main sources of bias
are likely to arise. Farmers participating in the project may dier from nonparticipants in their
observable characteristics due to project targeting, but they may also dier in unobservable
characteristics due to self-selection. These sources of bias will be addressed to the extent
allowed by the data and the sample design using nonexperimental methods.
3 Data and Method for Impact Evaluation
3.1 Data
The data used for the impact evaluation are from a baseline survey in 2012 and a follow-up
survey in 2013. Information about the sample design and data collection process was obtained
from reports provided by the rms hired to conduct data collection, and some gaps remain. A
local survey rm under the guidance of TechnoServe implemented the baseline survey during
JuneJuly 2012, prior to the implementation of the project. Two hundred and sixty-eight
participants (treatment households) and 510 nonparticipants (comparison households) were
randomly selected to be part of the study from eligible mango producers in a total of 12
communes.
The treatment households were selected from the communes where project activities were
implemented. The TechnoServe database was used to obtain the list of mango producers en-
rolled in the project. The comparison households were to be selected from the same communes
as the treated ones (Ba et al.). Since a list of farmers was not available for the compa-
rison group, households for this group were selected based on their geographical proximity
to the treatment households. The location of treated households was dened using as refer-
6
ence the communes' focal point for animators' project activities; the sites for data collection
were chosen randomly from the list of sites available.
7
The treated households interviewed
were chosen from within a virtual polygon|a 1km|side equilateral triangle whose centroid
coincide with the focal point of the animator's project activities|while control households
were identied in nearby areas with a high presence of mango production but outside the
intervention polygon (Schwartz,).
8
According to a project report, he sample size was determined to detect a 15 percent
point dierence in terms of change in key indicators for each group between the time of the
baseline and the time of the follow-up survey, with a probability of 0.05 that this change is
sample error, and a condence level of 95 percent. As a result, the sample size was calculated
to be 220 mango producers and increased to 250 to take into account possible dropouts in the
treatment group. For the comparison group, the sample size was doubled to 500" (Ba et al.,
2012).
9
But more observations were collected for the treatment (268) and comparison groups
(510) (Table 2).
10
The baseline survey collected information on household demographics, mango production
(including costs), and mango-harvesting practices, as well as information on project partici-
pation activities (that is, participation in various groups and associations) and the types of
training received by participants. Table 2 describes the sample distribution by treatment
status and by commune. The number of treated and control observations are not evenly
distributed across communes.
Table 3 compares socioeconomic characteristics between the treatment and the comparison
group. Performing the t-test for equal means of the socioeconomic characteristics between
the two groups shows there are statistically signicant dierences for some variables (7 out of
20 variables). In an average household in the treatment group, the household head is older
and more likely to be female. A typical treatment household also plants more non-Francique
trees and is more likely to rank mangos as their rst source of income and rst crop. Finally,
the wall materials of the residences of the treatment households are signicantly better than
those of control households (though the homes are small overall). And compared with the
control households, treatment households have less access to water from a river or well. This
descriptive evidence reinforces the early discussion that the direct comparison of outcome
variables between the treatment and control households leads to biased estimates, and thus
indicates the need for alternative evaluation methods to account for the existing dierences
between the two groups.
A dierent rm was hired to conduct the follow-up survey in October 2013. With inputs
from IDB and TechnoServe, the rm made a series of changes to the survey instruments. Only
some variables from the baseline survey (on production, commercialization, sales, participation
in training activities, and gender of household head) were kept. Additional questions on mango
production, crop production, and plot information were newly added to the follow-up survey.
Neither the baseline survey nor the follow-up survey collected any commune-level data. The
sample size was reduced from the original 778 to 474 (Papyrus,). Due to budgetary
constraints a limit of 450 observations was set, 200 treated and 250 nontreated (Papyrus,
7
The animator is the person in charge of contacting, recruiting, and training mango producers.
8
These geographic parameters were dened based on TechnoServe's experience with the project.
9
Unfortunately, this is the only information that is available to us regarding the sample design and power
calculation.
10
It is not clear from the project reports why the sample included more observations with respect to the
sample design.
7
2013). But the actual number of observations was 47424 more than planned. Of the 474
observations, 211 were of treatment households and 263 of control households. The sample
reduction most aected the observations of control households. The households interviewed in
the follow-up were selected randomly from the list of households interviewed for the baseline.
The number of treatment and control households was established to maximize statistical
power, given the restrictions imposed by the budget. We conducted attrition analysis to
determine whether the sample reduction aected our conclusions.
An additional 13 observations were not included in the baseline survey and were therefore
excluded from our study. The total number of observations that include information from
both the baseline survey and follow-up survey is 461205 treatment households and 261 control
households.
11
Table 4 shows the distribution of the nal observations used in our evaluation
analysis by commune and by treatment and control groups. As in the baseline survey, the dis-
tribution of observation is uneven across communes, with two extreme cases. While Verettes
has eight treatment observations but no control observation, the commune labeled as \other"
only has 29 control observations but no treatment observation (Table 4).
12
To check whether the attrited households and panel households are systematically dierent,
we compared their pretreatment household and mango production characteristics within both
the treated and control group, using data from the baseline survey (Table 5). Out of the
36 variables compared, we found statistically signicant dierences for ve variables in the
treatment group: the age of the household head in three categories (household head aged
4554, 3544, and 55 and more), and household access to water from a well and from a public
water source. Out of the same 36 variables, the dierence is statistically signicant for only
four variables in the control group: the age of household head in two categories (household
head aged 2534, and 55 and more), the number ofFranciquetrees, and the number of rooms.
These results suggest no systematic dierence exists between the attrited households and the
panel households for the treated and control groups. Therefore, attrition bias is unlikely to
aect our evaluation.
3.2 Methods
To estimate project impacts we use nonexperimental econometric methods to control for
selection biases. To estimate the average treatment eect on the treated (ATT) we use
propensity score matching (PSM); matching in covariates; dierence-in-dierence, propensity
score matching (DID-PSM); and DID matching in covariates.
We use PSM and matching in covariates for the outcomes for which we do not have
data from the baseline, namely the adoption of various production, harvest and postharvest,
and commercialization best practices, and use DID-PSM and DID matching for the set of
outcomes related to production and sales for which we have data from both the baseline and
the follow-up surveys.
Matching relies on the conditional independence assumption, or unconfoundedness, and
on the assumption of overlap (Heckman et al.,;,), which states that the
researcher should observe all variables simultaneously inuencing the participation decision
11
The fact that the number of observations is bigger in the control group than in the treatment group
is generally consistent with the sample requirement for matching analysis (Imbens and Wooldridge,;
Khandker et al.,;,).
12
Unfortunately we do not have further information on the sample design to explain why we observe this
distribution of treated and control observations within communes.
8
and outcome variables, and that there is overlap between the probability distributions of treat-
ment and control samples. With this method we control for bias on observable characteristics,
caused by the targeting of project beneciaries (for example, based on a set of eligibility cri-
teria). We conduct matching on the propensity score using kernel matching (Heckman et al.,
1997;,;,). Kernel matching is a nonparametric
method that uses a weighted average of all the observations in the control group to cons-
truct the counterfactual outcome for each treated observation (Smith and Todd,). The
weights depend on the type of kernel function chosen. An advantage of kernel matching is
that it reduces the variance of the estimates by using more information.
We also conduct matching in covariates (Abadie and Imbens,;,). This
estimator consists of matching all units, treated and control, using the distance between the
values of the covariates for each observation (in our case weighted by the sample variance
matrix). If the matching is done with replacement, the order of observations does not matter.
The matching can be conducted with one or more observations (one and ve in our case);
increasing the number of observations improves the quality of matching but increases the
variances of the estimates (Smith and Todd,). Since matching multiple covariates can
lead to substantial bias, it is combined with bias adjustment to remove most of the bias.
This approach uses linear regression to remove the bias associated with dierences in the
matched values of the covariates (Abadie and Imbens,;,). Bootstrapped
standard errors are calculated for matching estimates to account for the two-step PSM pro-
cedure (Abadie and Imbens,),
13
and robust standard errors are estimated for matching
on covariates (Abadie and Imbens,;,).
As mentioned earlier, PSM relies on the assumption of unconfoundedness. But it is likely
that there are systematic dierences in outcomes for participants and nonparticipants due to
unobservable characteristics, known as bias on unobservables. While it is impossible to directly
address this problem using cross-sectional data, we conduct Rosenbaum bounds analysis to
check the sensitivity of our estimates to deviations from the conditional independence assump-
tion (Rosenbaum,). For the outcome variables for which we have panel data, we use these
to estimate the impacts using the DID-PSM (Smith and Todd,) and DID-matching on
covariates. Both methods control for time invariant heterogeneity.
14
We follow a few standard procedures to estimate project impacts using the matching
methods (Imbens,;,;,). The rst step is
to estimate the propensity scores (PS) using a probit or logit model. The next step is to check
the overlap region of the estimated PS between the treatment and control group. Another
step is to trim the observations with PS close to zero and one.
We estimate PS using a logit model and test whether higher polynomial terms are needed
or not, following2002]. With the estimated PS we can check for overlap of
the probability distribution between the treated and control groups, by plotting the estimated
PS for the two groups. A substantial overlap is crucial in order for the PSM method to work.
Failing to identify substantial overlap is a major source of bias in PSM estimates of impacts
because the counterfactual group is not similar to the treatment group. Following standard
13
When conducting PSM, sensitivity analysis is also usually conducted to determine that the estimates are
not sensitive to dierent matching methods. But when conducting PSM with the nearest neighbor, we are
unable to obtain the correct standard errors for inference. For this reason we do not conduct PSM on the
nearest neighbor.
14
We lack data from before the baseline survey to test for parallel trends in treatment and control samples,
but we make this assumption as done in other studies without long historical data.
9
matching procedures, we prune the observations with an estimated PS above 0.90 and below
0.10 to improve overlap (Imbens and Wooldridge,;,;,).
With this trimmed sample we reestimate the PS and conduct the matching again.
We conduct a balancing test to check for the similarity of the marginal distribution of
the covariates used to estimate the PS. The test aims to determine whether the matching
procedures have served the purpose of making participants and nonparticipant groups more
similar. Covariates are compared via a measure of standardized bias or normalized dierences
in means (Imbens and Wooldridge,;,).
15
To assess covariate balance
we follow Imben's rule of thumb regarding percentage bias below 25 percent (Imbens and
Wooldridge,;,).
A potential concern is that the presence of similar projects in the study sites could po-
tentially bias the impact estimates. To check whether our estimated results are aected by
this, we conduct a robustness check by reestimating the impacts using a reduced sample that
includes only those households that have not participated in other projects, and compare the
new results with the ones obtained using the whole sample.
Because the conditional independence assumption is a strong one, we carry out a sensitivity
analysis to determine how strong an unmeasurable variable must be to inuence the selection
process and the outcome of interest as to undermine the conclusions. If there are unobservable
variables that simultaneously inuence participation and outcome variables, matching only
based on observable characteristics may lead to biased estimates. In order to determine how
sensitive the matching results are to deviations from the conditional independence assumption,
we also conduct the Rosenbaum bounds sensitivity analysis (Rosenbaum,), a popular
exercise after matching methods (Dillon,;,;,).
4 Results
In this section, we describe farmers' participation in various project activities. We then briey
present the results of PS regression and check the quality of matching. Most of our discussion
is devoted to the evaluation results based on PSM, matching on covariates, DID-PSM, and
DID-matching on covariates.
16
We conclude by discussing results from the robustness check
and Rosenbaum Bounds analysis.
17
4.1 Participation in Project Activities
Farmers' decision to participate in the program or not was voluntary. After one year of project
activities, over 50 percent of participants had received training in improved production and
harvest and postharvest practices, and business and commercialization practices (Table 6).
Meanwhile, 87 percent of beneciaries identied themselves as members of a PBG, and 56
percent or more as involved in PBG activities (Table 8). As can be seen in Table 6, Table
15
We use the normalized mean dierence instead of the standard t-test for equal means, because the former
does not depend on the sample size. For instance, the t-statistic may be large in absolute value simply because
the sample is large, and small dierences between sample means are statistically signicant even if the absolute
dierence is substantially small. For more details, please refer to2014],2009],
and2010].
16
For the estimation of the PS, PSM, and DID-PSM methods, we use psmatch2 in STATA (Leuven and
Sianesi,). For the matching in covariates and DID-matching in covariates we use nnmatch in STATA
(Abadie et al.,).
17
To estimate Rosenbaum bounds we use mhbounds in STATA (Becker and Caliendo,)
10
7, and Table 8, households in the control group also participate in activities similar to those
promoted by the project, which is explained by the presence of similar projects in the study
area (AGRITECH,;,). We address this issue (a possible source of
bias in our results) by conducting a robustness check, which will be discussed in section 4.7.
4.2 Propensity Score Estimation
The probability of program participation, or PS, is estimated using a logit model. The depen-
dent variable is a dichotomous variable for whether or not the household was a beneciary of
the project. The explanatory variables in the logit model are a set of variables from the base-
line survey that include information on household head characteristics, housing, children's
schooling, mango production and its perceived importance to household income, access to
water, access to markets, and so on.
First we estimate the PS with all the observations in the sample. Following standard
procedures for PSM, we trim the sample by eliminating the observations with PS>0.90
and PS<0.10, and reestimate the PS based on the trimmed sample (Imbens,;
and Wooldridge,;,). A total of eight nontreated observations were
trimmed. We check the specication of the PS using the method suggested by
Wahba2002]. We nd that we do not need to include higher polynomials of the variables,
or additional variables, for the estimation. Based on the estimated results of the logit model,
the beneciary households were more likely to be headed by a female, to cite mangoes as
their main source of income, and to have fewerFranciquemango trees than households in the
control group (Table 9). Beneciary households were also likely to lack access to water from
a river, spring, or pump, but had residences with more adequate wall materials (Table 9).
In order to visually examine how the beneciary and nonbeneciary households overlap
each other in terms of PS, we present in Figure 1 the predicted probability of selection for
the project among both treated and nontreated households.
As can be seen in Figure 1, there is overlap for a good range of PS except for a few
observations in the very right tail (PS>0.75). There are fewer control observations to match
treated ones at values greater than 0.75 of the estimated PS. This is not an issue for estimating
the program impacts using PSM, however, because we are able to nd nontreated observations
similar to the treated ones within a wide range of estimated PS values.
A useful criterion for measuring the quality of matching is to check the treated group
against the control group in terms of observed characteristics before and after matching.
Table 10 presents the dierence for the key variables between the treated and control
groups before and after matching. Figure 2 presents the estimated PS with the weighted
observationsboth treated and controlby the weights generated for the kernel matching algo-
rithm. We nd that matching improves the balance between the two groups, as supported by
the fact that the absolute value of normalized mean dierences between the treatment and
control groups is much smaller after matching than before matching for the majority of the
variables. In fact, the absolute value for the normalized dierence in means (percent bias) for
all the covariates is below 25 percent, an indicator of a good balance of covariates (Imbens
and Wooldridge,). For PSM and PSM-DID we conrm overlap improvement (see Figure
2).
11
4.3 Impacts on Production and Sales
We rst present the estimated impacts of the project using DID-PSM and DID matching in
covariates for the outcomes related to mango production and sales.
18
We then present the
results using PSM and matching in covariates for the adoption of best practices promoted by
the project. For both DID-PSM and PSM, we present the results based on kernel matching
methods.
Table 11 reports the estimated impacts of the project on the total number ofFrancique
mango trees, and whether these trees are productive or immature, as well as the total value
of sales. We estimate these impacts using DID-PSM and DID matching in covariates.
19
The
results suggest that the program has a signicant and positive eect on the total number of
Franciquetrees, and that these trees are young (that is, not yet productive). On average,
treated farmer households increased their number ofFranciquetrees by 12.3, and number of
immature trees by 12.4. These results are signicant at the 10 percent level, respectively, and
indicate that those newFranciquetrees are saplings planted by farmers as a result of project
participation. But when comparing the number of productiveFranciquetrees we nd no
statistically signicant dierence between the treatment and control groups. Consequently,
we do not nd any statistically signicant dierence in mango sales. It takes more than three
years for a mango tree to bear fruit and become productive (University of Hawai Manoa,
2014); it is therefore too early to expect newly planted trees to contribute to production and
sales.
4.4 Impacts on Adoption of Production Best Practices
In addition to promoting the planting ofFranciquetrees, the project also promotes the adop-
tion of best practices in production. Improving these practices is widely accepted as a neces-
sary condition for higher yields and prots in the future (IFAD,;,;
World Bank,). Since information on the adoption of these best practices is available only
from the follow-up survey, we estimate the program eects on these indicators using PSM and
matching in covariates to analyze the cross-sectional data. Table 12 reports the estimated
program eects on the adoption of various production best practices.
The results suggest that the project has signicantly increased the adoption of the produc-
tion best practices promoted by the projectthat is, pruning, tidying, grafting, and construction
of fences. The share of households who adopted these practices is signicantly (p-values less
than 0.10) higher in the treatment group than in the control group. Production practices such
as pruning prevent trees from getting too large; reshape intermediate trees into smaller, more
manageable ones; and rejuvenate large trees that are no longer productive (Davenport,).
Information from plot trials indicates that it takes more than a year of applying practices such
as pruning to translate into increases in fruit yield (Yeshitela et al.,). Therefore, it is not
surprising that the adoption of these improved practices has not yet translated into increases
18
We tested for the quality of the data collected for these variables using Benford's law (rst digit law)
(Judge and Schechter,). We nd that in general the data collected in the follow-up survey tend to follow
the law for most of the variables, except for the total number of young trees. But the baseline data tend not
to follow the law with the exception of the number of non-Franciquetrees.
19
Unlike PSM by itself, the DID estimator in the common support accounts for potential sources of selection
bias|potential unobserved, time invariant heterogeneity|whose xed component is cancelled out via dier-
encing data on treatment and controls before and after the intervention. Using the DID approach we control
for dierences in risk aversion, personality, and innate ability that might aect self-selection into the program.
12
in production and sales. Moreover, these results should be read with caution because they
are sensitive to the potential presence of selection bias (see section 4.8).
4.5 Impacts on Adoption of Harvest and Postharvest Best Practices
The results for harvest and postharvest best practices (sorting of mangos and transportation
for commercialization) are reported in Table 12, but the results are not statistically signicant
and indicate that farmers participating in the project did not adopt these practices. The
results suggest a statistically signicant increase in the use of ice sack on head" as a mean
of transportation, but the magnitude of the dierence is low.
According to TechnoServe, farmers are not adopting these best practices because they are
not the ones who carry out these activitiesspecialized harvesters who have not received the
training are the ones who do so; these specialized harvesters work for the middlemen.
4.6 Impacts on Marketing Channels Promoted by the Project
One intention of the project is to help mango farmers sell their mangoes through modern
market channels (the cell or PBG) instead of through traditional channels (middlemen), as
the latter are associated with higher transaction costs and lower bargaining power. The PSM
and matching in covariates results suggest, on the one hand, that the share of farmers who
sold their mangoes through a cell or PBG is signicantly higher, at the 1 percent level, in the
treatment group than in the control group (Table 12). On the other hand, the share of mango
farmers who sold their products to middleman is signicantly lower, at the 1 percent level, in
the treatment group than in the control group. These results indicate that the project has
been eective in promoting preferred commercialization channels among mango farmers.
4.7 Robustness Checks
One concern we have is that similar activities promoted by other organizations in the study
sites may have biased our estimated impacts (AGRITECH,;,). We
estimate project impacts for a subsample of treated and nontreated households that did not
receive any training from other organizations. We dropped the households that were reported
to have received training from organizations other than TechnoServe. In total we dropped
120 observations, 60 from the treated group and 60 from the control group. We conducted
this robustness check analysis with a total of 341 observations, 145 treated and 196 control
observations.
We estimate the PS using the same specication as in section 4.2 (Table 13). Following
standard procedures, we trimmed three observations with PS>0.90 and PS<0.10 and dropped
four additional observations because of missing data. A total of 334 observations were used for
the analysis. Table 13 presents the estimated PS model, and Figure 3 presents the estimated
PS for the reduced sample. Figure 4 displays the estimated PS for both treatment and control
households with the control observations, weighted by the weights generated by the kernel
matching algorithm. The latter conrms how matching improves the overlap between the
probability distribution treatment and control groups.
As can be seen from Table 14, the results for the reduced sample and the entire sample
are very similar both in terms of sign, magnitude, and level of signicance, suggesting that
our estimated results on project impacts are unlikely to be caused by other organizations
13
promoting similar interventions in the project areas. This is expected since there is no sta-
tistically signicant dierence in the proportion of producers that receive training from other
organizations, other than TechnoServe, in the treatment and control groups (Table 6). The
proportion of producers that receive training from other organizations remains statistically
the same in both groups after matching.
20
4.8 Sensitivity Analysis Using Rosenbaum Bounds
Finally we estimate the Rosenbaum bounds for the PSM results to assess the sensitivity and
reliability of the PSM estimates (Table 15).
21
Dierent values of correspond to dierent
assumptions on the eect of an unobservable variable in the odds ratio of treatment assignment
in otherwise similar casesin terms of the observable variables included in the participation
model. It has been argued that varying the values of from 0 to 2 (doubling the weight of
unobserved variables in the selection) is a sucient range to test the eect of hidden bias
(Aakvik,;,;,). As pointed out by2001], a
value of =2 implies that two subjects with the same observable characteristics dier in their
odds of participating in a program by a factor of two, or 100 percent, which is unlikely given
that the participation model adjusts for many important observable characteristics.
Given the positive signicant eects we obtain in our matching analysis, we rst present the
bounds results under the assumption that we overestimated project impacts due to positive
unobserved selection|that is, project participants are more likely than nonparticipants to
adopt best practices, and to sell their product via the channels recommended by the project.
We conduct the sensitivity analysis only for statistically signicant results. The sensitivity of
the estimated impacts to potential unobserved factors varies across variables (Table 15).
The results on the adoption of commercialization and harvest and postharvest best prac-
tices are insensitive to the potential eect of unobservable variables (columns 5{7) (Table 15).
For example, the estimated eects on the farmers' choice to sell products through a PBG or
cell, or through a middleman, remain signicant at the 1 percent level even after the odds
ratio of treatment assignment doubled (>2). That is, the results remain signicant at the 1
percent level even in the presence of an unobservable variable that causes the odds of partici-
pating in the program to dier by a factor of 2 for two subjects that have the same observable
characteristics. The result for selling to an association is insensitive to the eect of an unob-
servable variable that causes the odds ratio of treatment assignment to dier by more than
70 percent (or >1.7 column 4). To gain a better understanding of the magnitude of hidden
bias required to upset the latest, most sensitive result, we calculate the equivalent eect of
some observable variables included in the participation model: the eect of an unobservable
variable capable of causing the odds ratio of treatment assignment to dier by more than 1.7
would be equivalent to the eect of a dierence in 4.2 non-Franciquetrees, or a dierence in
59.1Franciquetrees for two otherwise identical producers.
Compared with the adoption of commercialization and harvest and postharvest best prac-
tices, the adoption of production best practices is more sensitive to the potential presence of
20
Although the evaluation was not designed to measure spillover eects (we do not include in the study
an additional group of mango producers located out of reach of the areas of intervention), some of the results
presented in Table 8 suggest that the impact of the study may be underestimated. Although producers in the
control group are formally not direct beneciaries of the project, they report to benet from activities carried
out and knowledge disseminated via PBG which suggest our estimates are conservative.
21
The sensitivity analysis is done using matched pairs|one near neighbor matching algorithm in our case.
See2007].
14
hidden bias (columns 1{3) (Table 15). The results for the construction of fences are insensitive
to hidden bias, with the positive eect staying signicant at the 10 percent level in the case
of the odds ratio of treatment assignment doubling (= 2). The results for pruning are also
reasonably insensitive, becoming not signicant at the 10 percent level for values of >1.5.
Of the three best practices associated with production, the results for grafting trees are the
most sensitive to the eects of unobservables: the estimated positive eect becomes not sig-
nicant at the 10 percent level when the odds ratio of treatment assignment reaches values
of >1.2 (Table 15). This amount of hidden bias is equivalent to the eect of a dierence
in 20.3Franciquetrees, or 14.3 in the number of non-Franciquetrees in the probability of
the producer being assigned to treatment. So, although the results for grafting trees are the
most sensitive to the potential presence of an unobservable variable aecting the odds ratio of
treatment assignment, the equivalent size eect of that variable is relatively largea dierence
of 20.3Franciquetrees|in otherwise similar mango producers.
The results for the assumption that we have underestimated project impacts due to nega-
tive unobserved selection|that is, participants in the project are less likely to adopt the best
practices|are less interesting (Becker and Caliendo,;,). We
nd that for the outcomes related to the adoption of improved practices (pruning, tidying,
grafting, and fencing), the p-values indicate that the results are insensitive for all the val-
ues of considered (columns 1{3) (Table 15). We obtain similar results for some of the
commercialization and harvest and postharvest best practices (columns 4 and 6) (Table 15).
The results of the sensitivity analysis suggest that, in most cases, we can be condent
that the estimated results are robust to the possible presence of selection bias. In some
cases|pruning, grafting|the results are sensitive to moderately strong, confounding variables
under the (worst-case scenario) assumption that such confounding variables have a strong
impact not only on selection but on the variable of interest. The assumption is that an
unobserved variable's eect on these results is so strong as to almost perfectly determine
whether the result would be bigger for the treatment (overestimation of treatment eect) or
control (underestimation of treatment eect) case in each pair of matched cases in the data.
5 Discussion and Conclusion
This study contributes to the scant but growing literature evaluating the impacts of agri-
cultural development programs using rigorous analysis approaches. In particular, this study
evaluates the ecacy of a project in promoting the early adoption of best practices. The
descriptive evidence suggests that farmers participating in the project are learning new prac-
tices, participating in extension activities, and being active in newly formed associations.
Methodologically, we use both the matching methods and the combination of DID and
matching methods to evaluate the short-term impacts of the project. We use these methods
to address the nonrandomized selection of program sites and farmers' self-selection into the
project. Five main results emerge. First, we nd that the project has positive and signicant
eects on the number of newFranciquemango trees, a variety that has better market and
export potential than other varieties. Second, the project has positive and signicant eects on
the adoption of the promoted production best practices such as pruning, tidying, and grafting
of mango trees, and fencing mango orchards to protect them from animals (results for pruning
and grafting should be interpreted with caution, since they are sensitive to possible deviations
from the identifying unconfoundedness assumption). Third, the project has no eect on the
15
adoption of harvest and postharvest best practices, mainly because the training is aimed at
mango producers but these activities are most often carried out by specialized harvesters.
Fourth, the project has signicant eects on the adoption of preferred commercialization
channels: specically, the project helps farmers shift from selling their mangoes to middleman
to selling them to PBGs, which increases revenues from mango sales by reducing transaction
costs and increasing mango farmers' bargaining power. It also has led farmers to sell mangoes
by the dozen instead of by tree or plot, which increases the price they get for mangos. Fifth,
the adoption of improved production practices and preferred marketing channels has not yet
translated into increases in production or sales. This is not surprising given that production
and total sales depend on new production methods to take eect and trees to mature|
processes that take several years at minimum.
We conduct additional analyses to address concerns that the main results might be aected
by other potential confounding factors. Results based on a subsample of households that did
not report participating in other programs are similar to results based on the whole sample;
these suggest that the results are robust to the presence of other similar programs in the
project areas. We estimate Rosenbaum bounds to check the sensitivity of the main results to
selection on unobservables. The bounds analyses suggest that except for two of the promoted
production best practices|grafting and prun|the main results are in general insensitive
to the eects of potential hidden bias. The most robust results are those related to the
commercialization channels.
16
Table 1:Household and institutional level interventions (2010{2016)
Household level interventions
Agricultural Best Practices
- Pruning
- Orchard maintenance: cleaning weeds, fencing
- Grafting
- Nursery management
- Harvest practices
Post harvest
- Postharvest handling
- Post harvest transportation for commercialization
Business and commercialization
- PBG formation and management
- Organization, governance and business planning
- Financial literacy
- Bookkeeping
Access to credit
- Credit for inputs
- Credit management
Other - O farm income generating activities
Institutional level interventions
Institutional development
- Facilitating partnerships with research institutions
to identify mango varieties suitable for processing
- Setting up market service centers
- Establishing direct relationships with exporters
- Collaborating with other donors and the government
to improve transportation infrastructure
- Work with stakeholders in the mango supply chain
to decrease transaction costs
- Improve circulation of information on prices
Table 2:Baseline data distribution, by commune
Commune
Treatment Control
Freq. Percent Freq. Percent
Boucan Carre 10 3.73 18 3.53
Ennery 19 7.09 37 7.25
Gros Morne 44 16.42 89 17.45
Hinche 30 11.19 10 1.96
La Chapelle 34 12.69 26 5.1
Mirebalais 29 10.82 72 14.12
Other 4 1.49 63 12.35
Petite Rivie Artibonite 33 12.31 104 20.39
Saut-D'Eau 18 6.72 48 9.41
Thomonde 35 13.06 43 8.43
Verettes 12 4.48
Observations 268 100 510 100
Total 778
Source: Authors' own calculation based on baseline survey 2012.
17
Table 3:Baseline data comparison, by household characteristics and mango production
Variables
Treatment Control
Di p-value
y
Mean Sd Mean Sd
Head Female 0.39 0.49 0.29 0.45 0.10 0.01
Head age 18{24 yrs 0.03 0.18 0.06 0.23 -0.02 0.12
Head age 25{34 yrs 0.18 0.38 0.16 0.37 0.02 0.52
Head age 35{44 yrs 0.24 0.43 0.26 0.44 -0.02 0.54
Head age 45{54 yrs 0.33 0.47 0.24 0.43 0.09 0.01
Head age 55 and older 0.22 0.42 0.29 0.45 -0.06 0.06
Francique(number) 7.16 11.94 7.60 12.40 -0.43 0.96
non-Francique(number) 9.68 15.73 15.58 24.57 -5.89 0.00
Mango 1st income source 0.36 0.48 0.23 0.42 0.13 0.00
Mango 2nd income source 0.38 0.49 0.38 0.49 0.00 0.96
Mango 3rd income source 0.21 0.41 0.25 0.44 -0.04 0.20
Mango 1st crop 0.45 0.50 0.25 0.43 0.20 0.00
Mango 2nd crop 0.36 0.48 0.37 0.48 -0.01 0.77
Mango 3rd crop 0.13 0.34 0.26 0.44 -0.12 0.00
Transport foot path 0.19 0.39 0.17 0.38 0.01 0.63
Transpot motorcycle 0.01 0.09 0.01 0.08 0.00 0.80
Transport PackAnimal 0.66 0.47 0.71 0.45 -0.05 0.18
Transport Pickup 0.07 0.25 0.08 0.27 -0.01 0.50
Transport Truck 0.01 0.11 0.00 0.06 0.01 0.30
Household members (number) 5.88 2.20 5.92 3.25 -0.04 0.85
Number of rooms (number) 2.80 0.99 2.78 1.27 0.02 0.79
Roof Cement 0.04 0.21 0.02 0.15 0.02 0.14
Roof Thatch 0.13 0.34 0.17 0.38 -0.04 0.16
Roof Tin 0.85 0.36 0.82 0.39 0.03 0.27
Wall Carton 0.01 0.11 0.00 0.04 0.01 0.17
Wall Wadd 0.09 0.29 0.14 0.35 -0.05 0.05
Wall Rock 0.48 0.50 0.55 0.50 -0.07 0.06
Wall Block 0.20 0.40 0.13 0.34 0.07 0.02
Wall Wood 0.07 0.25 0.02 0.14 0.05 0.00
Wall Palm 0.19 0.39 0.21 0.41 -0.02 0.49
Floor Tile 0.01 0.09 0.00 0.06 0.00 0.55
Floor Cement 0.43 0.50 0.40 0.49 0.03 0.44
Floor Earth 0.58 0.49 0.61 0.49 -0.03 0.43
Water Rain 0.09 0.28 0.11 0.31 -0.02 0.32
Water River 0.25 0.44 0.37 0.48 -0.11 0.00
Water Spring 0.43 0.50 0.44 0.50 -0.01 0.82
Water Pump 0.19 0.39 0.22 0.42 -0.03 0.28
Water Well 0.12 0.33 0.19 0.39 -0.07 0.01
Public Water 0.90 0.30 0.91 0.29 -0.01 0.63
Distance Water 1{5 minutes 0.24 0.43 0.26 0.44 -0.01 0.68
Distance Water 6{10 minutes 0.16 0.37 0.20 0.40 -0.04 0.12
Distance Water 11{30 minutes 0.21 0.41 0.19 0.39 0.02 0.52
Distance Water more 30 minutes 0.26 0.44 0.24 0.43 0.02 0.49
Distance Water onsite 0.12 0.33 0.11 0.31 0.02 0.52
Females 18 or younger in school 3.15 1.09 3.12 1.24 0.02 0.85
Males 18 or younger in school 3.05 1.10 3.05 1.12 0.00 0.94
Source: Authors' own calculation based on baseline survey 2012.
Note: Observations: 268 treatment, 510 control, total 778.
(y) for an unpaired samples t-test for equal means, with unequal sample size.
18
Table 4:Distribution by commune for the nal sample; observations with data in both the
baseline survey and the follow-up survey
Commune
Treatment Control
Freq. Percent Freq. Percent
Boucan Carre 10 4.88 13 5.08
Ennery 13 6.34 21 8.2
Gros Morne 37 18.05 43 16.8
Hinche 21 10.24 3 1.17
La Chapelle 28 13.66 11 4.3
Mirebalais 16 7.8 32 12.5
Other 0 0.00 29 11.33
Petite Rivie Artibonite 27 13.17 54 21.09
Saut-D'Eau 16 7.8 26 10.16
Thomonde 29 14.15 24 9.38
Verettes 8 3.9 0 0.00
Total 205 100 256 100
Total observations 461
Source: Authors' own calculation based baseline survey 2012 and
follow-up survey 2013.
19
Table 5:Comparison of baseline data from households in the analysis sample and those
dropped from the sample
Variable
Treatment group Control group
Panel Dropped Di Panel Dropped Di
sample sample sample sample
Head Female 0.38 0.4 -0.02 0.28 0.3 -0.02
Head age 18-24 yrs 0.02 0.06 -0.04 0.05 0.06 -0.01
Head age 25-34 yrs 0.16 0.25 -0.09 0.1 0.22 -0.12***
Head age 35-44 yrs 0.2 0.37 -0.17*** 0.28 0.23 0.05
Head age 45-54 yrs 0.36 0.22 0.14** 0.24 0.24 0
Head age 55 and older 0.26 0.1 0.16*** 0.33 0.25 0.08**
Francique(number) 7.02 7.62 -0.6 8.52 6.67 1.85*
Non-Francique(number) 9.99 8.68 1.31 15.04 16.16 -1.12
Mango 1st income source 0.36 0.38 -0.02 0.23 0.22 0.01
Mango 2nd income source 0.39 0.36 0.03 0.4 0.37 0.03
Mango 3rd income source 0.21 0.22 -0.01 0.25 0.26 -0.01
Mango 1st crop 0.43 0.48 -0.05 0.26 0.24 0.02
Mango 2nd crop 0.37 0.34 0.03 0.38 0.36 0.02
Mango 3rd crop 0.13 0.14 -0.01 0.25 0.26 -0.01
Transport foot path 0.18 0.21 -0.03 0.15 0.19 -0.04
Transpot motorcycle 0.01 0 0.01 0.01 0 0.01
Transport PackAnimal 0.67 0.62 0.05 0.73 0.69 0.04
Transport Pickup 0.08 0.03 0.05 0.08 0.08 0
Transport Truck 0.01 0.02 -0.01 0.01 0 0.01
Household members (number) 5.89 5.77 0.12 6.29 5.56 0.73***
Number of rooms (number) 2.81 2.77 0.04 2.74 2.83 -0.09
Roof Cement 0.04 0.06 -0.02 0.02 0.02 0
Roof Thatch 0.14 0.1 0.04 0.18 0.15 0.03
Roof Tin 0.84 0.89 -0.05 0.82 0.83 -0.01
Wall Carton 0.01 0.02 -0.01 0 0 0
Wall Wadd 0.1 0.08 0.02 0.14 0.13 0.01
Wall Rock 0.49 0.47 0.02 0.56 0.55 0.01
Wall Block 0.22 0.16 0.06 0.11 0.15 -0.04
Wall Wood 0.07 0.06 0.01 0.02 0.02 0
Wall Palm 0.18 0.23 -0.05 0.23 0.2 0.03
Floor Tile 0 0.02 -0.02 0 0.01 -0.01
Floor Cement 0.43 0.45 -0.02 0.39 0.41 -0.02
Floor Earth 0.59 0.56 0.03 0.63 0.6 0.03
Water Rain 0.08 0.11 -0.03 0.11 0.11 0
Water River 0.25 0.26 -0.01 0.36 0.38 -0.02
Water Spring 0.42 0.48 -0.06 0.45 0.44 0.01
Water Pump 0.2 0.18 0.02 0.23 0.22 0.01
Water Well 0.14 0.06 0.08* 0.19 0.18 0.01
Public Water 0.88 0.95 -0.07** 0.91 0.91 0
Distance Water 1-5 minutes 0.25 0.24 0.01 0.26 0.25 0.01
Distance Water 6-10 minutes 0.16 0.15 0.01 0.19 0.23 -0.04
Distance Water 11-30 minutes 0.21 0.23 -0.02 0.2 0.18 0.02
Distance Water more 30 minutes 0.25 0.31 -0.06 0.25 0.23 0.02
Distance Water onsite 0.14 0.08 0.06 0.11 0.11 0
Females 18 or younger in school 3.11 3.22 -0.11 3.17 3.08 0.09
Males 18 or younger in school 3.04 3.08 -0.04 3.04 3.06 -0.02
Source: Authors' own calculation based on baseline survey 2012 and follow-up survey 2013.
Note: Observations for the treated group, 204 panel observations and 63 dropped; for the control group,
256 panel observations and 252 dropped.
Signicance levels are indicated by: *** at the 1 percent level; ** at the 5 percent level; * at the 10
percent level.
20
Table 6:Farmers' participation in project training activities, 2013
Training activity
Treatment Control
Di.p-value
y
Mean Sd Mean Sd
Plot management 0.93 (0.26) 0.49 (0.50) 0.44 0.00
Pruning or tree care 0.68 (0.47) 0.29 (0.45) 0.39 0.00
Composting 0.6 (0.49) 0.28 (0.45) 0.32 0.00
Organic pest control 0.37 (0.48) 0.13 (0.34) 0.24 0.00
Nursery management 0.66 (0.47) 0.32 (0.47) 0.34 0.00
Harvest and post harvest practices 0.4 (0.49) 0.14 (0.35) 0.26 0.00
Internal transport 0.52 (0.50) 0.15 (0.36) 0.37 0.00
Business skills/SB production 0.59 (0.49) 0.19 (0.39) 0.4 0.00
Organizing groups 0.56 (0.50) 0.15 (0.36) 0.41 0.00
Income statement (calculating prots and loss) 0.52 (0.50) 0.18 (0.39) 0.34 0.00
Traceability or fair trade 0.53 (0.50) 0.14 (0.35) 0.39 0.00
Equality of men and women 0.62 (0.49) 0.19 (0.39) 0.43 0.00
Microcredit 0.53 (0.50) 0.16 (0.36) 0.37 0.00
Training from TNS 0.68 (0.47) 0.35 (0.48) 0.33 0.00
Training from other agencies 0.29 (0.46) 0.24 (0.43) 0.05 0.17
Observations 205 256
Total 461
Source: Authors' own calculation based on follow-up survey 2013.
(y)t-test of equal means, unpair unequal variance.
Table 7:Participation in project extension activities, 2013
Extension service and service for visit
z
Treatment Control
Di.p-value
y
Mean Sd Mean Sd
Fertilizer 0.13 0.33 0.05 0.22 0.08 0.01
Rehabilitating mango orchands 0.68 0.47 0.26 0.44 0.42 0.00
Planting mango orchands 0.34 0.48 0.17 0.38 0.17 0.00
Support for other production (no mango) 0.2 0.4 0.05 0.22 0.15 0.00
Irrigation equipment 0.27 0.45 0.11 0.31 0.16 0.00
Need seed varieties 0.32 0.47 0.05 0.22 0.27 0.00
Pest control support (pesticides or traps) 0.33 0.47 0.1 0.3 0.23 0.00
Help with soil (composting, errosion, etc) 0.29 0.46 0.08 0.28 0.21 0.00
Disaster mitigation (insurance) 0.63 0.48 0.24 0.43 0.39 0.00
Certied mango producer 0.49 0.5 0.11 0.32 0.38 0.00
Equitable certied mango producer 0.78 0.42 0.19 0.39 0.59 0.00
Organic certied mango producer 0.25 0.43 0.07 0.26 0.18 0.00
Observations 205 256
Total 461
Source: Authors' own calculation based on follow-up survey 2013.
(y)t-test of equal means, unpaired unequal variance.
(z)Services provided in situ by TechnoServe technicians.
21
Table 8:Participation in producer business group (PBG) or other association, 2013
Membership to farmers group
Treatment Control
Di.p-value
y
Mean Sd Mean Sd
PBG 0.87 0.33 0.33 0.47 0.54 0.00
Cooperative 0.12 0.32 0.05 0.22 0.07 0.01
Farmer association 0.51 0.50 0.30 0.46 0.21 0.00
Sell mangos to a PBG 0.71 0.46 0.32 0.47 0.39 0.00
Receive credit through a PBG 0.56 0.50 0.13 0.34 0.43 0.00
Participate in mango season planning with a PBG 0.72 0.45 0.19 0.39 0.53 0.00
Receive training from a neighbor or PBG member 0.80 0.40 0.34 0.47 0.46 0.00
Other activity with a cell 0.23 0.42 0.27 0.44 -0.04 0.55
Observations 205 256
Total 461
Source: Authors' own calculation based on follow-up survey 2013.
(y)t-test of equal means, unpaired unequal variance.
Table 9:Logit model results for propensity score estimation
Dependent variable: Project participant
n=449 (8 observations trimmed, 4 observations with missing
data)
Independent variables Coef. Std. Err. P >z
Female=1 0.41 0.22 0.06
Headage 0.02 0.04 0.63
Headagesq 0.00 0.00 0.61
Members (number) -0.03 0.05 0.52
Rooms (number) 0.04 0.11 0.73
Mango 1st to 3rd income source 1.43 0.64 0.03
Mango 1st to 3rd crop -0.44 0.59 0.46
Francique(number) -0.01 0.01 0.37
Non-Francique(number) -0.01 0.01 0.05
Footpath=1 -0.29 0.54 0.59
PackAnim=1 -0.48 0.50 0.34
Pickuptruck=1 -0.52 0.59 0.38
inadroof=1 0.20 0.66 0.76
inadwalls=1 -0.83 0.33 0.01
inadoor=1 -0.02 0.24 0.94
Waterriverspring=1 -0.68 0.29 0.02
Waterpumpwell=1 -0.70 0.27 0.01
PublicWater=1 -0.22 0.37 0.56
Distwater10minless=1 -0.19 0.26 0.47
DistWater1030=1 0.04 0.30 0.89
Girls in school(number) -0.08 0.10 0.46
Boys in school(number) 0.11 0.11 0.31
Constant 0.44 1.49 0.77
Log likelihood -289
Source: Authors' own calculation.
22
Table 10:Balancing tests for the matching procedure
Variable
Before matching After matching
Treatment Control
%bias p-value
Treatment Control
%bias p-value
Mean Mean Mean Mean
Female=1 0.38 0.28 15.03 0.03 0.38 0.34 9.4 0.35
Headage
47.44 47.96 -2.78 0.68 47.44 48.49 -7.9 0.41
Headagesq
2415 2484 -3.71 0.58 2416 2516 -7.7 0.43
Members (number) 5.91 6.09 -4.58 0.48 5.94 5.86 2.7 0.76
Rooms (number)
2.81 2.72 5.96 0.35 2.80 2.85 -4.6 0.66
Mango 1st to 3rd income source 0.96 0.89 18.69 0.01 0.96 0.96 0.0 1.00
Mango 1st to 3rd crop 0.94 0.89 12.75 0.08 0.94 0.97 -11 0.17
Francique(number) 7.03 7.71 -4.61 0.5 7.09 6.67 4.0 0.66
Non-Francique(number) 9.96 13.57 -14.26 0.03 10.03 10.58 -3.0 0.72
Footpath=1 0.18 0.15 5.72 0.31 0.18 0.16 5.3 0.60
PackAnim=1 0.67 0.73 -9.22 0.23 0.67 0.69 -4.3 0.67
Pickuptruck=1 0.09 0.09 0.00 0.86 0.09 0.07 6.8 0.46
inadroof=1 0.96 0.98 -8.47 0.25 0.96 0.93 20.2 0.13
inadwalls=1 0.79 0.88 -17.30 0.01 0.79 0.79 -1.3 0.90
inadoor=1 0.58 0.62 -5.71 0.37 0.58 0.59 -3.0 0.76
Waterriverspring=1 0.6 0.67 -10.31 0.13 0.60 0.54 12.3 0.23
Waterpumpwell=1 0.33 0.39 -8.84 0.18 0.33 0.33 0.0 1.00
PublicWater=1 0.88 0.91 -7.06 0.33 0.88 0.88 0.0 1.00
Distwater10minless=1 0.54 0.55 -1.41 0.82 0.54 0.53 3.0 0.77
DistWater1030=1 0.21 0.21 0.00 0.91 0.21 0.24 -7.2 0.48
Girls in school(number) 2.11 2.17 -3.59 0.58 2.12 2.17 -4.2 0.66
Boys in school(number) 2.04 2.02 1.24 0.85 2.05 2.01 3.9 0.68
Source: Authors' own calculation.
(*)Number of observations 203 treated, and 247 control.
%bias=
x1x2
q
s
2
1
+s
2
2
100
23
Table 11:Project impacts on outcomes related to production and sales, 2012{2013
DID-PSM DID-Matching in covariates
Kernel nn(5) nn(1)
Outcomes coef se coef se coef se
Production and sales (2013{2012):
DIFF Number ofFranciquetrees 12.29* (6.45) 11.34** (4.61) 9.60** (5.51)
DIFF Number of other type of mango trees 0.97 (6.83) -3.74 (4.88) -1.63 (6.31)
DIFF Total number of mango trees 12.98 (8.48) 8.78 (6.63) 12.52* (6.97)
DIFF Number of young mango trees 12.38* (7.30) 10.76** (5.38) 8.27 (7.14)
DIFF Number of productive mango trees -1.73 (7.07) -3.67 (5.24) -0.07 (3.63)
DIFF total sales USD 6.02 (44.88) -5.40 (34.63) -20.30 (48.56)
DIFF sales by tree USD 1.29 (2.34) 2.01 (2.31) 2.92 (2.37)
Source: Authors' own calculation based on baseline survey 2012 and follow-up survey 2013.
Note: DIFF = dierence; nn = nearest neighbor; coef = estimated coecient; se = standard error.
A total of 449 observations were used for matching, 203 treated and 246 controls, 4 observations o support.
For the DID-PSM estimation bootstrap standard errors with 500 repetitions in parenthesis; for the DID-
matching in covariates estimation, robust standard errors in parenthesis.
Signicance levels are indicated by: *** at the 1 percent level; ** at the 5 percent level; * at the 10 percent
level.
24
Table 12:The adoption of best practices promoted by the project, 2013
PSM Matching in covariates
Kernel nn(5) nn(1)
Outcomes coef se coef se coef se
Adoption of improved practices 2013:
Trim the mango tree 0.20*** (0.05) 0.21*** (0.05) 0.24*** (0.06)
Tidy up the mango tree 0.09* (0.05) 0.07 (0.05) 0.08 (0.05)
Clean up under the tree 0.02 (0.03) 0.02 (0.03) 0.05 (0.04)
SortFranciquemangos 0.02 (0.06) 0.01 (0.05) 0.03 (0.06)
Graft mango trees 0.12** (0.05) 0.16*** (0.05) 0.18*** (0.05)
Used fertiliser 0.03 (0.03) 0.00 (0.02) 0.02 (0.03)
Fenced in your plot 0.21*** (0.06) 0.20*** (0.05) 0.18*** (0.06)
Used pesticides 0.03 (0.03) 0.03 (0.02) 0.02 (0.02)
Commercialization behavior 2013:
Local market -0.07 (0.05) -0.06 (0.05) -0.04 (0.05)
Producer's association/neighbor 0.05** (0.02) 0.04** (0.02) 0.05*** (0.02)
Middlemen/Voltije -0.15*** (0.06) -0.16*** (0.05) -0.11* (0.06)
Exporter (factory) -0.01 (0.03) 0.01 (0.02) -0.02 (0.03)
PBG/Cell 0.43*** (0.05) 0.42*** (0.05) 0.38*** (0.05)
Postharvest practices 2013:
Straw bag on donkey -0.03 (0.06) 0.00 (0.05) 0.10 (0.07)
Rice sack on head 0.03* (0.02) 0.03 (0.02) 0.02 (0.01)
Peet bags -0.02 (0.02) -0.01 (0.02) -0.01 (0.03)
Basin on head 0.03 (0.03) 0.03 (0.03) 0.01 (0.03)
Improved straw 0.04 (0.02) 0.02 (0.03) 0.00 (0.03)
150 mango case 0.02 (0.04) 0.02 (0.03) 0.03 (0.04)
Small case -0.07 (0.05) -0.08 (0.05) -0.12** (0.06)
Wheelbarrow 0.01 (0.00) 0.01 (0.01) 0.01 (0.01)
Desirable method of transportation 0.06 (0.06) 0.02 (0.05) -0.01 (0.06)
Source: Authors' own calculation based on baseline survey 2012 and follow-up survey 2013.
Note: nn = nearest neighbor; coef = estimated coecient; se = standard error. A total of 449
observations were used for matching, 203 treated and 246 controls, 4 observations o support. For
DID-PSM estimation bootstrap standard errors with 500 repetitions in parentheses. For matching
in covariates estimation, robust standard errors in parenthesis.
Signicance levels are indicated by: *** at the 1 percent level; ** at the 5 percent level; * at the
10 percent level.
25
Table 13:Reduced sample Logit model for estimated propensity score
Dependent variable: Project participant
n=334 (3 observations trimmed, 4 observations with missing
data)
Independent variables Coef. Std. Err. P >z
Female=1 0.37 0.26 0.15
Headage 0.03 0.05 0.58
Headagesq 0.00 0.00 0.64
Members (number) -0.02 0.06 0.72
Rooms (number) 0.12 0.13 0.35
Mango 1st to 3rd income source 1.60 0.82 0.05
Mango 1st to 3rd crop -0.63 0.78 0.42
Francique(number) -0.01 0.01 0.56
Non-Francique(number) -0.01 0.01 0.09
Footpath=1 -0.13 0.69 0.85
PackAnim=1 0.01 0.62 0.98
Pickuptruck=1 -0.75 0.74 0.31
inadroof=1 0.61 0.83 0.46
inadwalls=1 -0.73 0.41 0.07
inadoor=1 0.04 0.28 0.87
Waterriverspring=1 -0.92 0.35 0.01
Waterpumpwell=1 -0.70 0.33 0.04
PublicWater=1 0.03 0.42 0.95
Distwater10minless=1 -0.13 0.31 0.67
DistWater1030=1 -0.24 0.36 0.51
Girls in school(number) -0.05 0.13 0.67
Boys in school(number) 0.11 0.13 0.40
Constant -1.20 1.75 0.49
Log likelihood -212
Source: Authors' own calculation based on baseline survey
2012 and follow-up survey 2013. n = 334.
26
Table 14:Reduced sample: DID-PSM project impacts on outcomes related to production
and sales, 2012{2013; PSM impacts on adoption of improved practices and changes in com-
mercialization behavior, 2013
Kernel
Reduced sample n=334 Whole sample n=449
Outcomes coef se coef se
Production and sales (2013-2012):
DIFF Number ofFranciquetrees 20.60*** (7.89) 12.29** (6.45)
DIFF Number of other type of mango trees -1.85 (9.94) 0.97 (6.83)
DIFF Total number of mango trees 18.67 (12.79) 12.98 (8.48)
DIFF Number of young mango trees 16.02 (10.41) 12.38* (7.30)
DIFF Number of productive mango trees 1.51 (8.05) -1.73 (7.07)
DIFF total sales USD 18.47 (42.67) 6.02 (44.88)
DIFF sales by tree USD 1.85 (3.13) 1.29 (2.34)
Adoption of improved practices 2013:
Trim the mango tree 0.21*** (0.06) 0.20*** (0.05)
Tidy up the mango tree 0.11* (0.06) 0.09* (0.05)
Clean up under the tree 0.05 (0.04) 0.02 (0.03)
SortFranciquemangos by distribution channel -0.01 (0.06) 0.02 (0.06)
Graft mango trees 0.19*** (0.06) 0.12** (0.05)
Used fertiliser 0.02 (0.02) 0.03 (0.03)
Fenced in your plot 0.17** (0.07) 0.21*** (0.06)
Used pesticides 0.03 (0.03) 0.03 (0.03)
Commercialization behavior 2013:
Local market -0.04 (0.05) -0.07 (0.05)
Producer's association/neighbor 0.06** (0.03) 0.05** (0.02)
Middlemen/Voltije -0.14** (0.07) -0.15*** (0.06)
Exporter (factory) 0.00 (0.03) -0.01 (0.03)
Cell 0.42*** (0.06) 0.43*** (0.05)
Postharvest practices 2013:
Straw bag on donkey -0.01 (0.06) -0.03 (0.06)
Rice sack on head 0.03* (0.01) 0.03* (0.02)
Peet bags 0.01 (0.02) -0.02 (0.03)
Basin on head 0.05 (0.03) 0.03 (0.03)
Improved straw 0.05* (0.03) 0.04 (0.02)
150 mango case 0.00 (0.04) 0.02 (0.04)
Small case -0.10* (0.06) -0.07 (0.05)
Wheelbarrow 0.01 (0.01) 0.01 (0.00)
Desirable method of transportation 0.05 (0.07) 0.06 (0.06)
Source: Authors' own calculation based on baseline survey 2012 and follow-up survey 2013.
Note: For DID-PSM and PSM estimation bootstrap standard errors with 500 repetitions in parenthesis.
For matching in covariates estimation, robust standard errors in parenthesis
Signicance levels are indicated by: *** at the 1 percent level; ** at the 5 percent level; * at the 10
percent level.
27
Table 15:Rosenbaum bounds for outcomes related to adoption of best practices (results for matching in covariates with one neighbor)
Pruning Grafting Fencing Producer Middlemen PBG/Cell Small case
association
(1) (2) (3) (4) (5) (6) (7)
p mh+ p mh- pmh+ p mh- pmh+ p mh- pmh+ p mh- pmh+ p mh- pmh+ p mh- pmh+ p mh-
1 0.00 0.00 0.01 0.01 0.00 0.00 0.02 0.02 0.01 0.01 0.00 0.00 0.02 0.02
1.1 0.00 0.00 0.03 0.00 0.00 0.00 0.03 0.01 0.00 0.04 0.00 0.00 0.01 0.04
1.2 0.01 0.00 0.06 0.00 0.00 0.00 0.04 0.01 0.00 0.08 0.00 0.00 0.00 0.09
1.3 0.02 0.00 0.11 0.00 0.00 0.00 0.05 0.01 0.00 0.15 0.00 0.00 0.00 0.16
1.4 0.04 0.00 0.17 0.00 0.00 0.00 0.07 0.00 0.00 0.23 0.00 0.00 0.00 0.24
1.5 0.08 0.00 0.25 0.00 0.01 0.00 0.08 0.00 0.00 0.34 0.00 0.00 0.00 0.33
1.6 0.12 0.00 0.34 0.00 0.02 0.00 0.10 0.00 0.00 0.44 0.00 0.00 0.00 0.43
1.7 0.18 0.00 0.43 0.00 0.03 0.00 0.12 0.00 0.00 0.54 0.00 0.00 0.00 0.53
1.8 0.25 0.00 0.52 0.00 0.05 0.00 0.13 0.00 0.00 0.45 0.00 0.00 0.00 0.47
1.9 0.33 0.00 0.49 0.00 0.08 0.00 0.15 0.00 0.00 0.36 0.00 0.00 0.00 0.39
2 0.41 0.00 0.41 0.00 0.12 0.00 0.17 0.00 0.00 0.28 0.00 0.00 0.00 0.31
Source: Authors' own calculation based on baseline survey 2012 and follow-up survey 2013.
: odds of dierential assignment due to unobserved factors
pmh+ : signicance level (assumption: overestimation of treatment eect).
pmh- : signicance level (assumption: underestimation of treatment eect).
28
Figure 1:Estimated propensity scores before matching
Source: Authors' own calculation based on baseline survey 2012 and follow-up survey 2013.
n=449.
Figure 2:Estimated propensity scores after matching (sample observations weighted using
kernel-matching weights)
Source: Authors' own calculation based on baseline survey 2012 and follow-up survey 2013.
n=449.
29
Figure 3:Estimated propensity scores before matching, reduced sample
Source: Authors' based on baseline survey 2012 and follow-up survey 2013. n= 334.
Figure 4:Estimated propensity scores after matching, reduced sample
Source: Authors' own calculation based on baseline survey 2012 and follow-up survey 2013.
n= 334.
30
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