Economic and social interaction takes place between individuals with heterogeneous characteristics. We investigate experimentally the emergence and informal enforcement of different contribution norms to a public good in homogeneous and different heterogeneous groups. When punishment is not...

In many economic contexts, an elusive variable of interest is the agent's expectation about relevant events, e.g. about other agents' behavior. Recent experimental studies as well as surveys have asked participants to state their beliefs explicitly, but little is known about the causal relation...

We aim to understand the role and evolution of beliefs in the indefinitely repeated prisoner's dilemma (IRPD). To do so, we elicit beliefs about the supergame strategies chosen by others. We find that heterogeneity in beliefs and changes in beliefs with experience are central to understanding...

We investigate corruption as a social dilemma by means of a bribery game in which a risk of collective sanction of the public officials is introduced when the number of officials accepting a bribe from firms reaches a certain threshold. We show that, despite the social risk, the pursuit of...

Social media has made anonymized behavior online a prevalent part of many people's daily interactions. The implications of this new ability to hide one's identity information remain imperfectly understood. Might it be corrosive to human cooperation? This paper investigates the possibility that a...

Using a negatively framed public good game, we study the cooperative behavior of individuals who reintegrate their group after being excluded by their peers. We manipulate the length of exclusion and whether this length is imposed exogenously or results from a vote. We show that people are...

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...

Does the supply of a welfare state create its own demand? Many economic scholars studying welfare arrangements refer to Say's law and insinuate a self-destructive welfare state. However, little is known about the empirical validity of these assumptions and hypotheses. We study the dynamic effect...

Well-functioning groups enforce social norms that restrain opportunism, but the social structure of a society may encourage or inhibit norm enforcement. Here we study how the exogenous assignment to different positions in an extreme social hierarchy - the caste system - affects individuals'...

Recent economic literature emphasizes the importance of moral considerations to explain compliance behavior with respect to underground activities such as tax evasion. A considerable amount of research aims to identify factors that affect the intrinsic motivation to comply. However, the causal...