We develop a simple theory which formally describes how charities can resolve the information asymmetry problems faced by small donors by working with large donors to generate quality signals. To test the model, we conducted two large-scale natural field experiments. In the first experiment, a...

We worked with two microlenders to test impacts of randomly assigned reminders for loan repayments in the “text messaging capital of the world." We do not find strong evidence that loss versus gain framing or messaging timing matter. Messages only robustly improve repayment when they include...

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....

Theories abound for why individuals give to charity. We conduct a field experiment with donors to a Yale University service club to test the impact of a promise of public recognition on giving. Some may claim that they respond to an offer of public recognition not to improve their social...

We evaluate the impact of a health information intervention implemented through mobile phones, using a clustered randomized control trial augmented by qualitative interviews. The intervention aimed to improve sexual health knowledge and shift individuals towards safer sexual behavior by...

Is financial knowledge change necessary for lasting behavior change? Or, akin to Friedman’s billiard player, can behavior persist “as if” such knowledge is held? We randomize 240 Ugandan young-adult clubs to financial education, savings account access, both, or neither. Each education arm,...

We were asked to discuss specific methodological approaches to evaluating three hypothetical interventions. This article uses this forum to discuss three misperceptions about randomized trials. First, nobody argues that randomized trials are appropriate in all settings, and for all questions....

Group liability in microcredit purports to improve repayment rates through peer screening, monitoring, and enforcement. However, it may create excessive pressure, and discourage reliable clients from borrowing. Two randomized trials tested the overall effect, as well as specific mechanisms....

Many social experiments are run in multiple waves, or replicate earlier social experiments. In principle, the sampling design can be modified in later stages or replications to allow for more efficient estimation of causal effects. We consider the design of a two-stage experiment for...

Firms spend billions of dollars each year advertising consumer products in order to influence demand. Much of these outlays are on the creative design of advertising content. Creative content often uses nuances of presentation and framing that have large effects on consumer decision making in...