A controversy has been simmering in law for at least 30 years about whether pro bono work should be mandatory for lawyers, who now donate 1-3% of their time to the poor. This has centered on the unmet legal needs of the poor, the duty of lawyers, and the contrast with US doctors, who are...

Frustration, anger, and aggression have important consequences for economic and social behavior, concerning for example monopoly pricing, contracting, bargaining, traffic safety, violence, and politics. Drawing on insights from psychology, we develop a formal approach to exploring how...

Social preference research has fundamentally changed the way economists think about many important economic and social phenomena. However, the empirical foundation of social preferences is largely based on laboratory experiments with self-selected students as participants. This is potentially...

This paper considers a dynamic model of the evolution of open source software projects, focusing on the evolution of quality, contributing programmers, and users who contribute customer support to other users. Programmers who have used open source software are motivated by reciprocal altruism to...

There is ample empirical evidence indicating that a substantial fraction of the population exhibits social preferences. Recent work also shows that social preferences influence the effectiveness of incentives in labor relations. Hence when making contracting decisions, employers should take into...