We examine a randomized trial that allows separate identification of peer screening and enforcement of credit contracts. A South African microlender offered half its clients a bonus for referring a friend who repaid a loan. For the remaining clients, the bonus was conditional on loan approval....

Group liability is often portrayed as the key innovation that led to the explosion of the microcredit movement, which started with the Grameen Bank in the 1970s and continues on today with hundreds of institutions around the world. Group lending claims to improve repayment rates and lower...

We study the design of randomized controlled experiments in environments where outcomes are significantly affected by unobserved effort decisions taken by the subjects (agents). While standard randomized controlled trials (RCTs) are internally consistent, the unobservability of effort provision...

This paper analyzes how private decisions and public policies are shaped by personal and societal preferences (values), material or other explicit incentives (laws) and social sanctions or rewards (norms). It first examines how honor, stigma and social norms arise from individuals’ behaviors...

We analyze a long-term contracting problem involving common uncertainty about a parameter capturing the productivity of the relationship, and featuring a hidden action for the agent. We develop an approach that works for any utility function when the parameter and noise are normally distributed...

An ‘efficiency wage’ model developed for Western economies is reinterpreted for Soviet Russia assuming that it was the Gulag not unemployment that acted as a ‘worker-discipline device’. Archival data now available allows for a basic account of the dynamics of the Gulag to be estimated....