Charness et al. (2007b) have shown that group membership has a strong effect on individual decisions in strategic games when group membership is salient through payoff commonality. In this comment, I show that their findings also apply to nonstrategic decisions, even when no outgroup exists, and...

Credence goods, such as car repairs or medical services, are characterized by severe informational asymmetries between sellers and consumers, leading to fraud in the form of provision of insufficient service (undertreatment), provision of unnecessary service (overtreatment) and charging too much...