In many cultures and industries gifts are given in order to influence the recipient, often at the expense of a third party. Examples include business gifts of firms and lobbyists. In a series of experiments, we show that, even without incentive or in-formational effects, small gifts strongly...

Behavioural economists have come to recognize that reciprocity, the interaction of trust and trustworthiness, is a distinct and economically relevant component of individual preferences alongside selfishness and altruism. This recognition is principally due to observed decisions in experimental...