Social preferences and self-control

We provide new evidence on the impact of diminished self-control on social preferences in the ultimatum game. In a sample of German university students (N=312), depleted proposers made lower offers, and depleted responders rejected unfair offers as often as non-depleted ones. This agrees with previous evidence on the Dictator Game but stands in contrast with a previous study with a sample of Spanish university students. A possible explanation is that selfish motives are the default mode of behavior, but there is individual heterogeneity on whether strategic fairness (fear of rejection) can overcome them.