Do demand characteristics contribute to minimal ingroup preferences?

"Minimal group" paradigms investigate social preferences arising from mere group membership. We asked whether demand characteristics contribute to children's apparent minimal group bias in a preregistered experiment (N = 160). In a group condition, we attempted to replicate findings of bias following assignment to minimal groups. A second closely matched no-group condition retained potential demand characteristics while removing group assignment. Parallel bias in the no-group condition would suggest that demand characteristics contribute to findings of apparent ingroup bias. Three main findings emerged. First, in the group condition, ingroup preference emerged in one of three bias measures only. Second, this preference emerged even though participants evaluated ingroup/outgroup photos varying in race/ethnicity between trials. Third, the measure that yielded ingroup preferences in the group condition produced no parallel bias in the no-group condition, consistent with the view that mere membership in a group, not experimental demand, leads to minimal ingroup preferences.