NGOs and other non-profit organizations attract workers who strongly identify themselves with their missions. We study whether these good guys are more trustworthy and how such pronounced group identities affect trust and trustworthiness within the groups and toward out-groups. We find that...

Because costly punishment is not credible, subgame perfection suggests that punishment will not deter free riding, regardless of the size or structure of groups. However, experiments show that people will punish free riders, even at considerable cost. To examine the implications of agents who...

We present an economic experiment on network formation, in which subjects can decide to form links to one another. Direct links are costly but being connected is valuable. The gametheoretic basis for our experiment is the model of Bala and Goyal (2000). They distinguish between two scenarios...

This paper reports the results of a laboratory experiment on network formation among heterogeneous agents. The experimental design extends the basic Bala-Goyal (2000) model of network formation with decay and two-way flow of benefits by allowing for agents with lower linking costs or higher...

This paper studies the effect of endogenous group formation on the outcome in two types of coordination games with multiple Pareto-ranked equilibria. Endogenous group formation means that in each period players are free to choose among two or more groups within which they want to play the...

Economic and social interactions often take place in open communities but the dynamics of the community choice process and its impact on cooperation of its members are yet not well understood. We experimentally investigate community choice in social dilemmas. Participants repeatedly choose...

We present an experiment on strategic thinking and behavior of individuals and teams in one-shot normal-form games. Besides making choices, decision makers have to state their first- and second-order beliefs. We find that teams play the Nash strategy significantly more often, and their choices...

We conduct a contribution game for a real public good and show that when the contributors value the real public good highly, they increase their contributions in each round. Thus, contrary to previous literature, free riding decreases over rounds and the end-game effect is reversed.

We conduct multi-person one-shot ultimatum games that reflect important aspects of collective bargaining. In all treatments a proposer has to divide a pie among herself and two groups of three recipients each. She cannot discriminate within, but across groups. A committee with representatives...

We investigate the effect of a donation incentive tied to contributions to a public good when group members can decide on the size of the donation to be made. An up to 20 % donation of the public good was implemented either exogenously or endogenously by group members. In the Vote treatment,...