Essays in microeconomics.

Summary In this dissertation, I study three topics in microeconomics: targeting, gambling, and retirement savings. The first chapter, based on joint work with Francis Bloch, examines an approach to targeting based on ranking by friends. A social planner aims to extract a ranking of individuals by asking each individual to rank their friends. We study how the structure of the community's social network determines the planner's ability to extract a truthful and effective ranking. Our analysis highlights the importance of common friends. The second chapter, based on joint work with Joshua Blumenstock, studies online sports betting, which has gained popularity in Kenya and other East African countries. We use a large dataset of sports betting transactions to provide evidence that gamblers can become overconfident in their ability to predict the outcome of games. We argue that overconfidence persists because gamblers overestimate how often their friends win and because gamblers overweight past successes relative to past failures. In the third and final chapter, I use a field experiment to study the impact of providing a retirement calculator on retirement savings to employees of a large South African company. The calculator provides retirement income projections and helps counter misperceptions of exponential growth. Although most employees are still saving at the minimum rate and the intervention was arranged to coincide with salary increases, the calculator did not result in significant increases in savings.