From the lab to the field: envelopes, dictators and manners

Results are reported of the first natural field experiment on the dictator game, where subjects are unaware that they participate in an experiment. In contrast to predictions of the standard economic model, dictators show a large degree of pro-social behavior. This paper builds a bridge from the laboratory to the field to explore how predictive findings from the laboratory are for the field. External validity is remarkably high. In all experiments, subjects display an equally high amount of pro-social behavior, whether they are students or not, participate in a laboratory or not, or are aware that they participate in an experiment or not.