Bram Thuysbaert

Ghent University
Sint-Pietersnieuwstraat 25
9000 Gent, Belgium

Institutional Affiliation: Ghent University

NBER Working Papers and Publications

October 2014Saving for a (not so) Rainy Day: A Randomized Evaluation of Savings Groups in Mali
with Lori Beaman, Dean Karlan: w20600
High transaction and contracting costs are often thought to create credit and savings market failures in developing countries. The microfinance movement grew largely out of business process innovations and subsidies that reduced these costs. We examine an alternative approach, one that infuses no external capital and introduces no change to formal contracts: an improved "technology" for managing informal, collaborative village-based savings groups. Such groups allow, in theory, for more efficient and lower- cost loans and informal savings, and in practice have been scaled up by international non-profit organizations to millions of members. Individuals save together and then lend the accumulated funds back out to themselves. In a randomized evaluation in Mali, we find improvements in fo...
August 2014Self-Selection into Credit Markets: Evidence from Agriculture in Mali
with Lori Beaman, Dean Karlan, Christopher Udry: w20387
We examine whether returns to capital are higher for farmers who borrow than for those who do not, a direct implication of many credit market models. We measure the difference in returns through a two-stage loan and grant experiment. We find large positive investment responses and returns to grants for a random (representative) sample of farmers, showing that liquidity constraints bind. However, we find zero returns to grants for a sample of farmers who endogenously did not borrow. Thus we find important heterogeneity, even conditional on a wide range of observed characteristics, which has critical implications for theory and policy.
November 2013Targeting ultra-poor households in Honduras and Peru
with Dean Karlan: w19646
For policy purposes, it is important to understand the relative efficacy of various methods to target the poor. Recently, participatory methods have received particular attention. We examine the effectiveness of a hybrid two-step process that combines a participatory wealth ranking and a verification household survey, relative to two proxy means tests (the Progress out of Poverty Index and a housing index), in Honduras and Peru. The methods we examine perform similarly to one another by various metrics. They all target most accurately in the cases of the poorest and the wealthiest households but perform with mixed results among households in the middle of the distribution. Ultimately, given similar performance, the analysis suggests that costs should be the driving consideration in choosin...

Published: Dean Karlan & Bram Thuysbaert, 2019. "Targeting Ultra-Poor Households in Honduras and Peru," The World Bank Economic Review, vol 33(1), pages 63-94. citation courtesy of

February 2013Profitability of Fertilizer: Experimental Evidence from Female Rice Farmers in Mali
with Lori A. Beaman, Dean Karlan, Christopher R. Udry: w18778
In an experiment providing fertilizer grants to women rice farmers in Mali, we found that women who received fertilizer increased both the quantity of fertilizer they used on their plots and complementary inputs such as herbicides and hired labor. This highlights that farmers respond to an increase in availability of one input by re-optimizing other inputs, making it challenging to isolate the returns to any one input. We also found that while the increase in inputs led to a significantly higher level of output, we find no evidence that profits increased. Our results suggest that fertilizer's impact on profits is small compared to other sources of variation. This may make it difficult for farmers to observe the impact of fertilizer on their plots, and accordingly this affects their ability...

Published: Lori Beaman & Dean Karlan & Bram Thuysbaert & Christopher Udry, 2013. "Profitability of Fertilizer: Experimental Evidence from Female Rice Farmers in Mali," American Economic Review, American Economic Association, vol. 103(3), pages 381-86, May. citation courtesy of

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