Research Topics

EPAR Technical Report #335
Publication Date: 11/21/2017
Type: Data Analysis
Abstract
EPAR has developed Stata do.files for the construction of a set of agricultural development indicators using data from the Living Standards Measurement Study - Integrated Surveys on Agriculture (LSMS-ISA). We are sharing our code and documenting our construction decisions both to facilitate analyses of these rich datasets and to make estimates of relevant indicators available to a broader audience of potential users. 
 
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EPAR Technical Report #356
Publication Date: 10/31/2017
Type: Data Analysis
Abstract

According to AGRA's 2017 Africa Agriculture Status Report, smallholder farmers make up to about 70% of the population in Africa. The report finds that 500 million smallholder farms around the world provide livelihoods for more than 2 billion people and produce about 80% of the food in sub-Saharan Africa and Asia. Many development interventions and policies therefore target smallholder farm households with the goals of increasing their productivity and promoting agricultural transformation. Of particular interest for agricultural transformation is the degree to which smallholder farm households are commercializating their agricultural outputs, and diversifying their income sources away from agriculture. In this project, EPAR uses data from the World Bank's Living Standards Measurement Study - Integrated Surveys on Agriculture (LSMS-ISA) to analyze and compare characteristics of smallholder farm households at different levels of crop commercialization and reliance on farm income, and to evaluate implications of using different criteria for defining "smallholder" households for conclusions on trends in agricultural transformation for those households.

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EPAR Technical Report #358
Publication Date: 09/30/2017
Type: Data Analysis
Abstract

Crop yield is one of the most commonly used partial factor productivity measures. It is used to estimate the ratio of quantity of crop output, generally measured in kilograms or tons, to a sole input, land area. Ongoing EPAR research explores the policy implications of measuring yield by area planted versus area harvested. In this brief, we consider implications for crop yield estimates of other decisions in how to construct yield measures from household survey microdata. Using data from three waves of the Tanzania National Panel Survey (TNPS) and two waves of the Ethiopia Socioeconomic Survey (ESS), both part of the World Bank’s Living Standards Measurement Study-Integrated Surveys on Agriculture (LSMS-ISA), we calculate separate crop yield estimates across survey waves following different decisions on disaggregating yield by gender(s) of the plot decision-maker(s) and for pure-stand and mixed stand (intercropped) plots, on including crop production from multiple growing seasons, and on how to treat outlier observations.

Our technical brief helps to illustrate some of the potential effects of decisions of how to construct and report yield estimates, focus on maize yield estimates. We observe large differences in maize yields between pure stand and mixed stand plots, though the differences vary between Tanzania and Ethiopia and depending on how outliers are treated. We observe strong patterns in maize yields by gender of the plot decision-maker in Tanzania, but the patterns differ in Ethiopia again depending on how outliers are treated. Conclusions around maize yield do not seem to vary across sub-populations of plots when short rainy season production is added to long rainy season production in Tanzania, though these yield estimates are larger. These findings demonstrate that interpretations of crop yield estimates should pay particular attention to the decisions made in arriving at those estimates and the directions of bias potentially introduced by those decisions.

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EPAR Technical Report #357
Publication Date: 08/01/2017
Type: Literature Review
Abstract

Land tenure refers to a set of land rights and land governance institutions which can be informal (customary, traditional) or formal (legally recognized), that define relationships between people and land and natural resources (FAO, 2002). These land relationships may include, but are not limited to, rights to use land for cultivation and production, rights to control how land should be used including for cultivation, resource extraction, conservation, or construction, and rights to transfer – through sale, gift, or inheritance – those land use and control rights (FAO, 2002). Land tenure security – i.e., the level of confidence landholders have in their land rights – depends on the ability of informal and formal institutions to enforce those land rights and prevent others from challenging them (Feder & Feeny, 1991). In low and middle income countries land tenure security has been linked to improved land management including greater investments to improve land and agricultural productivity (Deininger & Jun, 2006; Deininger, Ali, & Alemu, 2011; Ali, Deininger, & Goldstein, 2014; Lawry et al., 2017). Having legal documentation in particular has been associated with a greater sense of ownership over land, increases in land productivity and capital investments associated with land, and in some cases additional financial opportunities such as access to credit for landholders with formal land titles (Deininger, Ali, & Alemu, 2011). But in spite of the widely recognized benefits of land tenure security more than 70 percent of the world’s population – and in particular many poor and vulnerable populations including ethnic minorities, smallholder farmers, and women – still lack access to formal systems to register their property and receive legally recognized land titles (Place, 2009; Enemark et al., 2014; Mitchell et al. 2016). 

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EPAR Technical Report #326
Publication Date: 06/01/2017
Type: Data Analysis
Abstract

Previous EPAR research identified a high level of year-to-year change in crop portfolios by farmers, as well as large-magnitude changes in cultivated area, particularly for smallholders. This implies that farmers may be open to changes in crop mix influenced by development interventions targeting certain crops. Many agricultural development interventions focus on increasing land productivity, in particular relying on crop-focused strategies that emphasize raising yields of major cereal crops. Such interventions often assume that as farmers become more productive, they will specialize increasingly in their most productive crop, while relatively less productive farmers will shift to other crops, or shift out of farming into other rural employment, or migrate to look for urban employment. However, many smallholder farmers in Sub-Saharan Africa face constraints that also shape their livelihood decisions and may result in different farmer responses to land productivity changes than expected.

By examining how farmers respond to changes in crop yield, we provide evidence on how farmers are likely to respond to a yield-enhancing intervention that targets a single staple crop such as maize. Two alternate hypotheses we examine are: as yields increase, do farmers maintain output levels but change the output mix to switch into other crops or activities, or do they hold cultivated area constant to increase their total production quantity and therefore their own consumption or marketing of the crop? This exploratory data analysis is part of a long-term project examining the pathways between staple crop yield (a proxy for agricultural productivity) and poverty reduction in Sub-Saharan Africa. 

We use panel data from three waves of the Tanzania National Panel Survey (TNPS) to investigate how Tanzanian farmers adjust their land allocation to maize following a change in their maize yield. We first evaluate whether households that experienced increasing maize yield from 2008-2010 (yield increasers) against those experiencing decreasing maize yield (yield decreasers) exhibit any shared baseline household, farm, or livelihood characteristics. We then use OLS and logistic regressions to analyse how much a change in maize yield within a given household is associated with changes in cropland allocation to maize versus other crops, controlling for household, farm, and geographic characteristics. Our results indicate that higher maize yields in 2010 are positively associated with increases in maize land allocation from 2010-2012 both as a land area value and when considering a household’s area share to maize, but that increases in maize yield from 2008-2010 are not significantly associated with maize planting decisions. A better understanding of the ways farmers respond to increases in maize yields will allow for better-informed and better-targeted investments in agriculture, and could inform ongoing structural transformation debates.

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EPAR Technical Report #347
Publication Date: 03/17/2017
Type: Literature Review
Abstract

A growing body of evidence suggests that empowering women may lead to economic benefits (The World Bank, 2011; Duflo, 2012; Kabeer & Natali, 2013). Little work, however, focuses specifically on the potential impacts of women’s empowerment in agricultural settings. Through a comprehensive review of literature this report considers how prioritizing women’s empowerment in agriculture might lead to economic benefits. With an intentionally narrow focus on economic empowerment, we draw on the Women’s Empowerment in Agriculture Index (WEAI)’s indicators of women’s empowerment in agriculture to consider the potential economic rewards to increasing women’s control over agricultural productive resources (including their own time and labor), over agricultural production decisions, and over agricultural income. While we recognize that there may be quantifiable benefits of improving women’s empowerment in and of itself, we focus on potential longer-term economic benefits of improvements in these empowerment measures.

We consider the case for spending the marginal dollar on empowering female farmers as a means of increasing household productivity, either prioritizing women for new investments or re-allocating existing resources. The literature suggests at least two distinct avenues via which economic benefits from investing in women’s empowerment in agriculture might arise. The first is by equalizing access to productive resources (including access to and control over land, labor, and other inputs) between men and women, and the second by leveraging differences between men and women that might lead to improved household outcomes. For the first avenue, we consider two theorized pathways to economic benefits from women’s empowerment in agriculture that posit reducing female farmers’ constraints would allow them to be as productive as equivalent male farmers. Pathway 1 focuses on empowering women through increasing their access to and control over agricultural inputs, thereby increasing overall agricultural productivity by reducing gender productivity gaps. Pathway 2 focuses on women’s control over their own time and labor, hypothesizing that removing constraints to women’s mobility would increase overall household labor productivity.

In the second avenue, we consider three further theorized pathways from increasing women’s decision-making power over agricultural decisions to economically beneficial individual and household outcomes, given assumed male-female differences in decision-making under similar circumstances. Pathway 3 connects differences in men’s and women’s decisions of what crops to grow with household nutrition outcomes. Pathway 4 hypothesizes that differences in plot management between men and women, specifically women’s greater likelihood of intercropping, influence farm soil quality and long-term household agricultural productivity. Finally, Pathway 5 draws a connection between differences in how men and women spend income from agriculture to impacts on household nutrition and education outcomes. We note that any measured benefits from leveraging male-female differences in the resource choices they make may dissipate as women gain more access and control if the differences are not due to being a woman per se, but rather stem from being disempowered - since this would change the circumstances in which evidence of these differences in decision-making have been observed. 

This review of the literature ultimately shows some - but not conclusive - support for portions of all five theorized causal pathways between women’s economic empowerment in agriculture and economic returns. The literature also provides some dissenting evidence surrounding women’s constraints and preferences, most notably highlighting that results surrounding returns to empowerment can be context specific. We also note some inconsistencies in published methods and findings, and several key data gaps. First, published estimates of economic returns to empowering women in agriculture are still relatively rare, are mostly non-experimental, and are often limited in terms of data quality. Second, while published estimates provide some indication that, in many contexts, economic returns to women’s empowerment might be substantial, differences in measurement and reporting impede readily comparing benefits across contexts. Third, key variables necessary for extrapolating study findings to broader estimates of the benefits of economic empowerment – including basic variables such as land area managed by women – are not readily available. Finally, data on the costs of interventions addressing (eliminating or leveraging) the male-female differences in the five pathways are limited, making calculations of potential returns per dollar of investment difficult.

EPAR Research Brief #344
Publication Date: 08/10/2016
Type: Research Brief
Abstract

This brief presents an overview of EPAR’s previous research related to gender. We first present our key takeaways related to labor and time use, technology adoption, agricultural production, control over income and assets, health and nutrition, and data collection. We then provide a brief overview of each previous research project related to gender along with gender-related findings, starting with the most recent project. Many of the gender-related findings draw from other sources; please see the full documents for references. Reports available on EPAR’s website are hyperlinked in the full brief. 

EPAR Technical Report #240
Publication Date: 07/28/2016
Type: Data Analysis
Abstract

There is a wide gap between realized and potential yields for many crops in Sub-Saharan Africa (SSA). Experts identify poor soil quality as a primary constraint to increased agricultural productivity. Therefore, increasing agricultural productivity by improving soil quality is seen as a viable strategy to enhance food security. Yet adoption rates of programs focused on improving soil quality have generally been lower than expected. We explore a seldom considered factor that may limit farmers’ demand for improved soil quality, namely, whether farmers’ self-assessments of their soil quality match soil scientists’ assessments. In this paper, using Tanzania National Panel Survey (TZNPS) data, part of the Living Standards Measurement Study – Integrated Surveys on Agriculture (LSMS-ISA), we compare farmers’ own assessments of soil quality with scientific measurements of soil quality from the Harmonized World Soil Database (HWSD). We find a considerable “mismatch” and most notably, that 11.5 percent of survey households that reported having “good” soil quality are measured by scientific standards to have severely constrained nutrient availability. Mismatches between scientific measurements and farmer assessments of soil quality may highlight a potential barrier for programs seeking to encourage farmers to adopt soil quality improvement activities. 

EPAR Technical Report #337
Publication Date: 06/20/2016
Type: Data Analysis
Abstract

Relative to chronic hunger, seasonal hunger in rural and urban areas of Africa is poorly understood. No estimates are compiled, and limited evidence exists on prevalence, causes, and impacts. This paper contributes to the body of evidence by examining the extent and potential drivers of seasonal hunger using panel data from the Malawi Integrated Household Panel Survey (IHPS). Farmers are commonly thought to use various strategies to smooth consumption, including planting “off-season” crops, investing in post-harvest storage technologies, or generally diversifying farm portfolios including livestock products and/or wild crops. Similarly, when markets are available, farmers may diversify through off-farm income sources in order to purchase food in lean seasons. We investigate whether seasonal hunger – distinct from chronic hunger – exists in Malawi, drawing on two waves of panel data from the LSMS-ISA series. We examine the extent of seasonal hunger, factors associated with variation in seasonal hunger, and how recurring and longer-term seasonal hunger might be associated with various household welfare measures. We find that both urban and rural households report experiencing seasonal hunger in the pre-harvest months, with descriptive evidence suggesting male gender, age, and education of household head, livestock ownership, and storage of crops are associated with lower levels of seasonal hunger. In addition, we find that Malawian households with seasonal hunger harvest crops earlier than average – a short-term coping mechanism that can reduce the crop’s yield and nutritional value, possibly perpetuating hunger.

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EPAR Technical Report #336
Publication Date: 03/04/2016
Type: Data Analysis
Abstract

Common estimates of agricultural productivity rely upon crude measures of crop yield, typically defined as the weight harvested of a crop divided by the area harvested. But this common yield measure poorly reflects performance among farm systems combining multiple crops in one area (e.g., intercropping), and also ignores the possibility that farmers might lose crop area between planting and harvest (e.g., partial crop failure). Drawing on detailed plot-level data from the LSMS-ISA in Tanzania, Nigeria, and Ethiopia, we show how various yield measurement decisions affect estimates of smallholder yields for a variety of crops. We consider the effect of measuring production by plot area, area planted, and area harvested, of trimming the top 1% and 2% of values, and of considering different groups of farmers according to total area planted.