In this paper we provide experimental evidence indicating that incentive contracts may cause a strong crowding out of reciprocity-driven voluntary cooperation. This crowding out effect constitutes costs of incentive provision that have been largely neglected by economists. In our experiments the...

In recent years a large number of experimental studies have documented the existence of strong reciprocity among humans. Strong reciprocity means that people willingly repay gifts and punish the violation of cooperation and fairness norms even in anonymous one-shot encounters with genetically...