Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
This paper presents an experiment investigating whether decision makers discriminate between members of their own group and members of another group. I focus on two aspects of this question: First, I compare behavior in individual and in joint decisions; Second, I test whether the identity of the co-decision maker matters in joint decisions. Substantial own group favoritism occurs in joint decisions in spite of there being no such favoritism in individual decisions. Decision makers strongly favor own group candidates when deciding with someone from their own group, but not when deciding with someone from the other group. The study suggests that higher-order beliefs about co-decision maker behavior may be a factor behind discrimination in collective settings and that diversity in committees might be helpful in counteracting own group favoritism.