This paper presents a formal theory of reciprocity. Reciprocity means that people reward kind actions and punish unkind ones. The theory takes into account that people evaluate the kindness of an action not only by its consequences but also by the intention underlying this action. The theory...

Repeated interactions provide a prominent but paradoxical hypothesis for human cooperation in one-shot interactions. Intergroup competitions provide a different hypothesis that is intuitively appealing but heterodox. We show that neither mechanism reliably supports the evolution of cooperation...

This paper investigates how group membership and competition among trustors interact with trust and trustworthiness in a laboratory one-shot trust game. To analyze these effects, we apply a 2x2 design. We induce group membership by letting subjects play coordination games with clear focal...

This chapter presents some insights from basic behavioural research on the role of human pro-social motivation to maintain social order. I argue that social order can be conceptualized as a public good game. Past attempts to explain social order typically relied on the assumption of selfish and...

We consider rules (strategies, commitments, contracts, or computer programs) that make behavior contingent on an opponent's rule. The set of perfectly observable rules is not well defined. Previous contributions avoid this problem by restricting the rules deemed admissible. We instead limit the...

During the last two decades economists have made much progress in understanding incentives, contracts and organisations. Yet, they constrained their attention to a very narrow and empirically questionable view of human motivation. The purpose of this paper is to show that this narrow view of...

Empirical evidence is provided for the importance of non-reciprocal pro-social behavior of individuals in an anonymous, n-person pure public good setting. A unique panel data set of 136,000 observations is matched with an extensive survey. Even under anonymous conditions, a large number of...

We explore how inherent preferences for reciprocity and repeated interaction interact in an optimal incentive system. Developing a theoretical model of a long-term employment relationship, we first show that reciprocal preferences are more important when an employee is close to retirement. At...

This paper analyzes a dynamic relational contract for employees with reciprocal preferences. I develop a tractable model to investigate how “direct” performance-pay (promising a bonus in exchange for effort) and generous upfront wages (which activate the norm of reciprocity) interact over...

Indirect reciprocity is defined as a specific kind of behavior: An agent rewards or penalizes another agent for having behaved kindly or unkindly toward a third party. This paper analyzes the question of what drives indirect reciprocity: Does the agent reward or penalize because she...