We conducted a controlled field experiment on eBay and examined to what extent both social and competitive laboratory behavior is robust to institutionally complex real world markets with experienced traders, who selected themselves into these markets. EBay's natural trading system provides...

Retributive responses do play a role in human behavior. Whether they are primarily triggered by supposed intentions or by observed consequences of actions is an important question. It can be addressed by experimental studies of retributive responses in situations in which the individual actor...

Fairness is a strong concern as shown by the robust results of dictator giving and ultimatum experiments. Efficiency, measured by the sum of individual payoffs, is another potential concern in games such as the prisoners’ dilemma and public good provision games. In our experiment participants...