Gharad T. Bryan

London School of Economics
Houghton Street
London WC2A 2AE
United Kingdom

E-Mail: EmailAddress: hidden: you can email any NBER-related person as first underscore last at nber dot org

NBER Working Papers and Publications

February 2018Randomizing Religion: The Impact of Protestant Evangelism on Economic Outcomes
with James J. Choi, Dean Karlan: w24278
To test the causal impact of religiosity, we conducted a randomized evaluation of an evangelical Protestant Christian values and theology education program that consisted of 15 weekly half-hour sessions. We analyze outcomes for 6,276 ultra-poor Filipino households six months after the program ended. We find significant increases in religiosity and income, no significant changes in total labor supply, assets, consumption, food security, or life satisfaction, and a significant decrease in perceived relative economic status. Exploratory analysis suggests the program may have improved hygienic practices and increased household discord, and that the income treatment effect may operate through increasing grit.
June 2017The Aggregate Productivity Effects of Internal Migration: Evidence from Indonesia
with Melanie Morten: w23540
We estimate the aggregate productivity gains from reducing barriers to internal labor migration in Indonesia, accounting for worker selection and spatial differences in human capital. We distinguish between movement costs, which mean workers will only move if they expect higher wages, and amenity differences, which mean some locations must pay more to attract workers. We find modest but important aggregate impacts. We estimate a 22% increase in labor productivity from removing all barriers. Reducing migration costs to the US level, a high mobility benchmark, leads to an 8% productivity boost. These figures hides substantial heterogeneity. The origin population that benefits most sees an 104% increase in average earnings from a complete barrier removal, or a 37% increase from moving to the ...
May 2014Under-investment in a Profitable Technology: The Case of Seasonal Migration in Bangladesh
with Shyamal Chowdhury, Ahmed Mushfiq Mobarak: w20172
Hunger during pre-harvest lean seasons is widespread in the agrarian areas of Asia and Sub-Saharan Africa. We randomly assign an $8.50 incentive to households in rural Bangladesh to temporarily out-migrate during the lean season. The incentive induces 22% of households to send a seasonal migrant, their consumption at the origin increases significantly, and treated households are 8-10 percentage points more likely to re-migrate 1 and 3 years after the incentive is removed. These facts can be explained qualitatively by a model in which migration is risky, mitigating risk requires individual-specific learning, and some migrants are sufficiently close to subsistence that failed migration is very costly. We document evidence consistent with this model using heterogeneity analysis and additio...

Published: Gharad Bryan & Shyamal Chowdhury & Ahmed Mushfiq Mobarak, 2014. "Underinvestment in a Profitable Technology: The Case of Seasonal Migration in Bangladesh," Econometrica, Econometric Society, vol. 82, pages 1671-1748, 09. citation courtesy of

March 2012Referrals: Peer Screening and Enforcement in a Consumer Credit Field Experiment
with Dean Karlan, Jonathan Zinman: w17883
Empirical evidence on peer intermediation lags behind many years of lending practice and a large body of theory in which lenders use peers to mitigate adverse selection and moral hazard. Using a simple referral incentive mechanism under individual liability, we develop and implement a two-stage field experiment that permits separate identification of peer screening and enforcement effects. We allow for borrower heterogeneity in both ex-ante repayment type and ex-post susceptibility to social pressure. Our key contribution is how we deal with the interaction between these two sources of asymmetric information. Our method allows us to cleanly identify selection on the likelihood of repayment, selection on the susceptibility to social pressure, and loan enforcement. We estimate peer effects o...

Published: Gharad Bryan & Dean Karlan & Jonathan Zinman, 2015. "Referrals: Peer Screening and Enforcement in a Consumer Credit Field Experiment," American Economic Journal: Microeconomics, vol 7(3), pages 174-204. citation courtesy of

NBER Videos

National Bureau of Economic Research, 1050 Massachusetts Ave., Cambridge, MA 02138; 617-868-3900; email:

Contact Us