Is Generosity Time-Inconsistent? Present Bias across Individual and Social Contexts
通过纵向实验，研究人们在为自己和为他人做跨期分配决策时是否存在动态不一致的时间偏好，发现现时偏向仅出现在个人决策中，而慷慨行为本身并不存在时间不一致性。
Abstract We investigate dynamically inconsistent time preferences across contexts with and without interpersonal trade-offs. In a longitudinal experiment, participants make a series of intertemporal allocation decisions of real-effort tasks between themselves and another person. Our results reveal that agents are present-biased when making choices that affect only themselves but not when choosing on behalf of others. Despite this asymmetry, we find no evidence for time-inconsistent generosity, that is, when choices involve trade-offs between one's own and others' consumption. Structural estimations reveal no individual-level correlation of present bias across contexts. Discounting in social situations thus seems to be conceptually different from discounting in individual situations.