COVID-19 vaccines are widely available in wealthy countries, yet many people remain unvaccinated. Understanding the effectiveness -- or lack thereof -- of popular vaccination campaign strategies is therefore critical. In this paper, we report results from two studies that tested strategies...

COVID-19 vaccines are widely available in wealthy countries, yet many people remain unvaccinated. Understanding the effectiveness -- or lack thereof -- of popular vaccination campaign strategies is therefore critical. In this paper, we report results from two studies that tested strategies...

Can improved access to credit jump-start microenterprise growth? We examine subjects in urban Hyderabad, India, six years after microfinance–an intervention commonly believed to lower the cost of credit and spark business creation–was randomly introduced to a subset of neighborhoods. We find...

During the COVID-19 epidemic, many health professionals started using mass communication on social media to relay critical information and persuade individuals to adopt preventative health behaviors. Our group of clinicians and nurses developed and recorded short video messages to encourage...

We study how the introduction of microfinance changes the networks of interactions among 16476 households in 75 Indian villages, and develop a new dynamic model of network formation to explain the empirical findings. None of the villages were exposed to microfinance by 2006, and 43 villages were...

Can we identify the members of a community who are best- placed to diffuse information simply by asking a random sample of individuals? We show that boundedly-rational individuals can, simply by tracking sources of gossip, identify those who are most central in a network according to "diffusion...