Betrayal aversion versus principled trustfulness—How to explain risk avoidance and risky choices in trust games

Are decisions in a trust game more or less sensitive to changes in risk than decisions in a purely financial, non-social decision-making task? Participants in a binary trust game (they could either keep $5 for sure or give it to a trustee with the chance of getting $10 back) were informed that their chance of interacting with a trustworthy person was either 46 percent or 80 percent and then were asked to decide whether to trust that other person. In addition, participants made a decision in a lottery (i.e., whether to gamble $5 to win $10) with the same probabilities. In the 46 percent condition, participants were significantly more willing to choose the risky option in the trust game than in the lottery. Overall, the difference in probability of receiving money back had a significantly higher impact on the lottery decision than on the decision to trust. Possible interpretations of the present study and its relation to previous findings are discussed.

► Are trust decisions just sensitive to changes in risk as are decisions to gamble against nature? ► Trust game participants interacted with a person who was either 46 percent or 80 percent likely to honor that trust. ► Participants also decided whether to gamble on a lottery with the same payoffs and probabilities for themselves. ► In the 46 percent condition, participants were significantly more willing to risk money by trusting another person than they were to play the lottery. ► Overall, the chance of gaining money back impacted decisions to gamble in the lottery much more than decisions to trust another person.