Evans School Policy Analysis & Research Group (EPAR)

Precise agricultural statistics are necessary to track productivity and design sound agricultural policies. Yet, in settings where intercropping is prevalent, even crop yield can be challenging to measure. In a systematic survey of the literature on crop yield in low-income settings, we find that scholars specify how they estimate the yield denominator in under 10% of cases. Using household survey data from Tanzania, we consider four alternative methods of allocating land area on plots that contain multiple crops, and explore the implications of this measurement decision for analyses of maize and rice yield. We find that 64% of cultivated plots contain more than one crop, and average yield estimates vary with different methods of calculating area planted. This pattern is more pronounced for maize, which is more likely than rice to share a plot with other crops. The choice among area methods influences which of these two staple crops is found to be more calorie-productive per ha, as well as the extent to which fertilizer is expected to be profitable for maize production. Given that construction decisions can influence the results of analysis, we conclude that the literature would benefit from greater clarity regarding how yield is measured across studies.

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. 

Household survey data are a key source of information for policy-makers at all levels. In developing countries, household data are commonly used to target interventions and evaluate progress towards development goals. The World Bank’s Living Standards Measurement Study - Integrated Surveys on Agriculture (LSMS-ISA) are a particularly rich source of nationally-representative panel data for six Sub-Saharan African countries: Ethiopia, Malawi, Niger, Nigeria, Tanzania, and Uganda. To help understand how these data are used, EPAR reviewed the existing literature referencing the LSMS-ISA and identified 415 publications, working papers, reports, and presentations with primary research based on LSMS-ISA data. We find that use of the LSMS-ISA has been increasing each year since the first survey waves were made available in 2009, with several universities, multilateral organizations, government offices, and research groups across the globe using the data to answer questions on agricultural productivity, farm management, poverty and welfare, nutrition, and several other topics.

This four-part analysis describes the current suite of food security measures, then analyzes the respective relationships between food security and poverty, GDP, and crop yields using findings from in-depth literature reviews. Food security measures are criticized for inaccurately characterizing food security at individual, household, and national scales, yet guidelines exist to prescribe a food security measure for a given situation. Some authors see the potential of a combination of indicators that apply at different scales rather than a single, universal food security measure. Limited literature exists on the relationship between food security and poverty, GDP, or crop yields. The relationship between food security and poverty is particularly challenging because neither term has a consistent definition, and the limited literature suggests a lack of consensus among experts. Little empirical research exists on the relationship between food security and GDP, though studies generally note an association between the two Studies that evaluate food security and crop yields provide limited evidence that the two are associated, though many studies use measures of crop yield as food security indicators and vice versa. More research is needed to establish whether there are preferred food security measurement tools for specific scales and situations, and to further explore the relationship between food security and poverty, GDP, and crop yields.