Selfish behavior can plague the formation of cooperative relationships and collective efforts. Understanding ways in which groups can overcome selfish motives and foster cooperation, therefore, becomes essential. Recent research reveals that reputation systems promote cooperation and deter antisocial behavior in groups. Little is known, however, about how and why people share reputational information. In this dissertation, I seek to establish the existence and dynamics of prosocial gossip, the sharing of negative evaluative information about a target in a way that protects others from antisocial or exploitative behavior. I present a model of prosocial gossip and the results of five studies testing the model's claims. Results of Studies 1-3 demonstrate that (a) individuals who observe an antisocial act experience negative affect and are compelled to share information about the antisocial actor with a potentially vulnerable person, (b) sharing such information reduces negative affect created by observing the antisocial behavior, (c) individuals possessing more prosocial orientations are the most motivated to engage in such gossip, even at a personal cost, and exhibit the greatest reduction in negative affect as a result. Taken together these results highlight the roles of prosocial motivations and negative affective reactions to injustice in maintaining reputational information sharing in groups. Studies 4-5 explore two ways in which prosocial gossip can effectively deter selfishness and promote cooperation. Study 4 reveals that prosocial gossip promotes cooperation by deterring selfish behavior, especially among those who are more egoistic and prone to exploit others. Study 5 demonstrates how prosocial gossip fosters cooperation by facilitating partner selection, guiding the recipients of the gossip in selecting who to interact with and who to ostracize. I conclude by discussing implications for reputational theories of the maintenance of cooperation in human groups and laying out possibilities for future research.

Recent research on status and group productivity has highlighted that status hierarchies encourage contributions to group efforts by rewarding contributors with enhanced status. However, that and other work has typically assumed that status hierarchies are widely agreed-upon among group members. Here we challenge this assumption, proposing that groups vary in their level of hierarchical consensus and that when groups fail to achieve high agreement, the status rewards motivating contributions are attenuated, undermining group performance. Results of two studies of task groups support our claims. We observed that status disagreements were quite common, particularly those in which two group members both viewed themselves as higher in status than the other, and that more dominant individuals were most likely to engage in these types of disagreements. Further, we found that such status disagreements led to diminished group performance and that this effect was driven by reduced contributions from the group members involved. These findings suggest that status consensus can vary substantially across groups, and that groups that are able to successfully coalesce around agreed-upon status hierarchies benefit from increased contributions and performance.

This dissertation emerges out of an effort to understand the supra-individual aspects of attitudes and tastes, and especially those political attitudes that make up "public opinion." Various theoretical accounts conceive of large-scale attitude systems in terms of fields, shared schemas, cultural logics, or partisan ideologies. Though diverse, these accounts all depict attitudes as structural phenomena, defined by patterns of relations between cultural, cognitive, or social elements. In the three substantive chapters, I draw on network analysis, statistics, information theory, and computer science to create original methods for such structural analyses. I use them to provide new insights on culture as both individual cognition and macro-scale social organization. The first project examines networks of political attitudes. I find that, across subgroups, attitudes either follow the dominant liberal-conservative logic, or lack systemic organization. In the second project, I clarify and extend existing theories of cultural schemas to develop a greatly improved approach to detecting them in surveys. In the final project, I approach political attitudes as a field of competition. If public opinion is a debate between competing ideological camps, do the camps at least agree on which issues they are debating? My analyses of the skill with which individuals at different positions in the opinion space report their attitudes suggests that no such agreement exists.