The development of ingroup favoritism in repeated social dilemmas.

In two comprehensive and fully incentivized studies, we investigate the development of ingroup favoritism as one of two aspects of parochial altruism in repeated social dilemmas. Specifically, we test whether ingroup favoritism is a fixed phenomenon that can be observed from the very beginning and remains stable over time, or whether it develops (increases vs. decreases) during repeated contact. Ingroup favoritism is assessed through cooperation behavior in a repeated continuous prisoner's dilemma where participants sequentially interact with 10 members of the ingroup (own city and university) and subsequently with 10 members of the outgroup (other city and university), or vice versa. In none of the experiments do we observe initial differences in cooperation behavior for interaction partners from the ingroup, as compared to outgroup, and we only observe small differences in expectations regarding the interaction partners' cooperation behavior. After repeated interaction, however, including a change of groups, clear ingroup favoritism can be observed. Instead of being due to gradual and potentially biased updating of expectations, we found that these emerging differences were mainly driven by the change of interaction partners' group membership that occurred after round 10. This indicates that in social dilemma settings ingroup favoritism is to some degree dynamic in that it is enhanced and sometimes only observable if group membership is activated by thinking about both the interaction with the ingroup and the outgroup.

Ironic Effects of Sexual Minority Group Membership: Are Lesbians Less Susceptible to Invoking Negative Female Stereotypes than Heterosexual Women?

The traditional stereotype of the typical woman has been described as "nice, but incompetent." However, such general gender stereotypes are applied to individual targets only under certain conditions: They are used to "fill in the blanks" (Heilman, 2012) if little personal information is provided about a target. "Typical lesbians" are regarded to have more typically masculine (agentic) characteristics such as task competence than the typical woman does. We thus hypothesized that if a woman displays behavior coinciding with the stereotype of the typical woman, it is more readily interpreted as stereotypically female if performed by a heterosexual woman than by a lesbian. Participants (N = 296) read a hypothetical job interview in which we manipulated the target's sexual orientation (between subjects). Findings demonstrated that a lesbian was judged as more competent than a heterosexual woman in the presence of behavior that may be interpreted as gender-stereotypical (Experiments 1 and 2). This difference in competence judgments was not found in the absence of gender-stereotypical behavior (Experiment 1). Judging the heterosexual woman as low in masculinity was related to a judgment of lower competence (Experiment 2). Our findings demonstrate that there are conditions under which lesbians, a group often stereotyped negatively, are less susceptible to invoking negative female stereotypes than heterosexual women are.