Sex Differences in Trust and Trustworthiness - A Meta-Analysis of the Trust Game and the Gift-Exchange Game

Do men and women differ in trusting behavior? This question is directly relevant to social, economic, and political domains, yet the answer remains elusive. In this paper, we present a meta-analytic review of the literature on sex differences in the trust game and a variant, the gift-exchange game. Informed by both evolutionary and cultural perspectives, we predicted men to be more trusting and women to be more trustworthy in these games. The trust game meta-analyses encompass 77 papers yielding 174 effect sizes based on 17,082 participants from 23 countries, while the gift-exchange game meta-analyses covered 15 papers reporting 35 effect sizes based on 1,362 participants from 19 countries. In the trust game, we found men to be more trusting than women, g = 0.22, but we found no significant sex difference in trustworthiness, g = 0.09. In the gift-exchange game we found no significant sex difference in trust, g = 0.15, yet we did find that men are more trustworthy than women, g = 0.33. The results of the meta-analyses show that the behavior in both games is inconsistent. It seems that when monetary transfers are multiplied men behave more cooperatively than women, but that there are no sex differences when such a multiplier is absent. This “male multiplier effect” is consistent with an evolutionary account emphasizing men’s historical role as resource provider. However, future research needs to substantiate this effect and provide a theoretical framework to explain it.