The emergence of competition is a defining aspect of human nature and characterizes many important social environments. However, its relationship with how social groups are formed has received little attention. We design an experiment to analyze how individuals' willingness to compete is...

We examine the characteristics of effective leaders in a simple leader-follower voluntary contributions game. We focus on two factors: the individual's cooperativeness and the individual's beliefs about the cooperativeness of others. We find that groups perform best when led by those who are...

We report an experiment comparing sequential and simultaneous contributions to a public good in a quasi-linear two-person setting. In one parameterization we find that overall provision is lower under sequential than simultaneous contributions, as predicted, but the distribution of contributions...

Social preferences and social influence effects ("peer effects") are well documented, but little is known about how peers shape social preferences. Settings where social preferences matter are often situations where peer effects are likely too. In a gift-exchange experiment with independent...

A burgeoning literature in economics has started examining the role of social norms in explaining economic behavior. Surprisingly, the vast majority of this literature has studied social norms in asocial decision settings, where individuals are observed to act in isolation from each other. In...

Using a laboratory experiment, we investigate whether a variety of behaviors in repeated games are related to an array of individual characteristics that are popular in economics: risk attitude, time preference, trust, trustworthiness, altruism, strategic skills in one-shot matrix games,...

We introduce a novel approach to studying behavior in repeated games - one that is based on the psychology of play. Our approach is based on the following six "aspects" of a player's behavior: round-1 cooperation, lenience, forgiveness, loyalty, leadership, and following. Using a laboratory...

Economists are increasingly using experiments to study and measure discrimination between groups. In a meta-analysis containing 447 results from 77 studies, we find groups significantly discriminate against each other in roughly a third of cases. Discrimination varies depending upon the type of...

Substantial evidence suggests the behavioral relevance of social preferences and also the importance of social influence effects ("peer effects"). Yet, little is known about how peer effects and social preferences are related. In a three-person gift-exchange experiment we find causal evidence...

We study the interplay between leading-by-example and group identity in a public goods game experiment. A common identity between the leader and her followers is beneficial for cooperation: average contributions are more than 30% higher than in a treatment where no identity was induced. In two...