When working together, people engage in non-contractual and informal interactions that constitute the sociology of the group. We use behavioral models and a unique survey of medical groups to analyze how group sociology influences physician incentive pay and behavior. We conclude that informal...

This paper analyses competition of moral norms and institutions in a society where a fixed share of people unconditionally complies with norms and the remaining people act selfishly. Whether a person is a norm-complier or selfish is private knowledge. A model of voting-by-feet shows that those...