Reciprocity as a Contract Enforcement Device: Experimental Evidence
实验表明，当市场双方都有机会进行互惠行为时，互惠能显著增强合同执行力并提高交易效率，而单边互惠的效果取决于激励制度细节。
Numerous experimental studies indicate that people tend to reciprocate favors and punish unfair behavior. It is hypothesized that these behavioral responses contribute to the enforcement of contracts and, hence, increase gains from trade. It turns out that if only one side of the market has opportunities for reciprocal responses, the impact of reciprocity on contract enforcement depends on the details of the pecuniary incentive system. If both sides of the market have opportunities for reciprocal responses, robust and powerful reciprocity effects occur. In particular, reciprocal behavior causes a substantial increase in the set of enforceable actions and, hence, large efficiency gains.