Research Topics

EPAR Research Brief #316
Publication Date: 12/13/2015
Type: Literature Review
Abstract

The literature on poverty’s causes and cures in developing countries posits a variety of contributing factors. Most researchers acknowledge that a sustained exit from poverty is complex and no single causal pathway from poverty to non-poverty exists. In this review, we present a summary framework for categorizing the various theorized pathways out of poverty, and evaluate the empirical evidence for which interventions and resulting outcomes are most frequently and most strongly associated with poverty alleviation. We conducted a literature review on pathways out of poverty for low-income households in developing countries and identified and categorized general strategies and outcomes demonstrated to be empirically associated with poverty alleviation. We organized the general strategies into four asset groups that could be targeted to alleviate poverty: human, natural, built / financial, and social / political. Much of the literature presents positive results on poverty alleviation, but it is difficult to compare across studies because many of the studies were conducted in different countries and at different scales, and use a variety of outcome measures.

EPAR Technical Report #303
Publication Date: 08/10/2015
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 Tanzania’s National Panel Survey, our research contrasts measures of smallholder productivity using production per hectare harvested and production per hectare planted.

An initial analysis (Research Brief - Rice Productivity Measurement) looking at rice production finds that yield by area planted differs significantly from yield by area harvested, particularly for smaller farms and female-headed households. OLS regression further reveals different demographic and management-related drivers of variability in yield gains – and thus different implications for policy and development interventions – depending on the yield measurement used. Findings suggest a need to better specify “yield” to more effectively guide agricultural development efforts.

 

EPAR Research Brief #312
Publication Date: 07/30/2015
Type: Literature Review
Abstract

This brief reviews the evidence of realized yield gains by smallholder farmers attributable to the use of high-quality seed and/or improved seed varieties. Our analysis suggests that in most cases, use of improved varieties and/or quality seed is associated with modest yield increases.  In the sample of 395 trials reviewed, positive yield changes accompanied the use of improved variety or quality seed, on average, in 10 out of 12 crops, with rice and cassava as the two exceptions.

EPAR Technical Report #245
Publication Date: 04/10/2015
Type: Data Analysis
Abstract

A farmer’s decision of how much land to dedicate to each crop reflects their farming options at the extensive and intensive margins. The extensive margin represents the total amount of agricultural land area that a farmer has available in a given year (referred to interchangeably as ‘farm size’ or ‘agricultural land’). A farmer increases land use on the extensive margin by planting on new agricultural land. The intensive margin represents area planted of crops as a proportion of total farm size. A farmer increases the intensive margin by increasing output within a fixed area. This analysis examines cropping patterns for households in Tanzania between 2008 and 2010 using data from the Tanzania National Panel Survey (TZNPS).  This brief describes changes in farm size, total area planted, and area planted of select annual crops to highlight the dynamic nature of farmer’s cropping choices for a sample population of 2,246 agricultural households that reported having any agricultural land in 2008 or 2010. Throughout the brief, we present summary statistics at the national level and compare them with household-level data to show how results vary depending on how the sub-population is defined and how average measures can mask household level changes. We analyze these questions in the context of smallholders (defined as households with total agricultural land area as less than two hectares) and farming systems.  

EPAR Technical Report #293
Publication Date: 03/31/2015
Type: Literature Review
Abstract

This report reviews the current body of peer-reviewed scholarship exploring the impacts of morbidity on economic growth. This overview seeks to provide a concise introduction to the major theories and empirical evidence linking morbidity – and the myriad different measures of morbidity – to economic growth, which is defined primarily in terms of gross domestic product (GDP) and related metrics (wages, productivity, etc.). Through a systematic review of published manuscripts in the fields of health economics and economic development we further identify the most commonly-used pathways linking morbidity to economic growth. We also highlight the apparent gaps in the empirical literature (i.e., theorized pathways from morbidity to growth that remain relatively untested in the published empirical literature to date).

EPAR Technical Report #5
Publication Date: 12/15/2008
Type: Literature Review
Abstract

As our understanding of the impacts of hidden hunger on human nutrition grows, understanding the link between fertilizer use and human nutrition becomes increasingly important. This report presents an analysis of both grey and peer-reviewed literature on the effects of fertilizer use on nutritional quality of food, particularly the staples of maize, rice, wheat, cassava and legumes. We find that some nutrient deficiencies, such as zinc, can be effectively addressed through fertilizer use while others, such as iron deficiency, are more difficult to address.  Promising breakthroughs with fortified and complete fertilizers present the opportunity to correct multiple deficiencies. Current fertilizer products exist that, when applied with the proper agronomic methods, can have a significant effect on nutrition in the developing world.  However, it is important to recognize that there are many factors in the developing world that have the potential to inhibit the benefits of fertilizer for human nutrition.  Two significant factors are poor farmers’ difficulty in procuring the correct product and the relative sophistication required to apply fertilizers at the correct amounts and time to achieve desired results.  In addition, researchers have not focused on fertilizer and nutrition studies until recently, particularly micronutrient fertilizer studies, and few studies specifically study the impacts of fertilizer on human nutrition.  More research needs to be done to understand the most effective combinations and techniques, and to understand whether these methods truly increase the amount of nutrients bioavailable to humans. 

EPAR Research Brief #2
Publication Date: 10/30/2008
Type: Literature Review
Abstract

This brief reviews the literature on the links between agriculture and human nutrition in rural South Asia, exploring why South Asia has experienced enormous growth in agricultural productivity without subsequent reductions in hunger.  An annotated review of relevant articles is included in addition to the analysis.  The articles are presented by sub-topic, including sustained economic growth versus lack of progress in nutrition rates and hunger in South Asia, primary determinants of improved nutrition at the household level, agricultural productivity/reform and interventions in nutritional status.

EPAR Research Brief #4
Publication Date: 10/22/2008
Type: Literature Review
Abstract

We conducted a literature review of strategic grain reserves (SGRs) are used to mitigate food crises. Our brief includes a short overview of the literature and a bibliography of top-cited articles relevant to specific sub-topics related to SGRs.