Intuitive Prosociality: Heterogeneous Treatment Effects or False Positive?

Heterogenous treatment effects make it difficult to extrapolate from one research setting to another. However, what appears to be differences in effects across subpopulations may simply be false positives. This paper uses a representative sample of the Norwegian population (N = 1390) to systematically test for several proposed sources of heterogeneity in the literature on intuitive prosociality – a literature with large variation in results, which some researchers claim results from heterogeneity in the underlying effect. We use time pressure to induce intuitive decision making, and exogenously vary participants’ experience with the game. We find no overall effect of time constraints on dictator game for inexperienced subjects, and there is no evidence for an interaction effect between subject experience and the effect of time pressure. As a more general test of treatment effect heterogeneity, we consider the full distribution of treatment effects conditional on various proposed moderators in the literature. The distribution of conditional effects is consistent with no causal effect of time pressure on giving and no systematic heterogeneity in the underlying effect across subpopulations.