Global social identity and global cooperation.

This research examined the question of whether the psychology of social identity can motivate cooperation in the context of a global collective. Our data came from a multinational study of choice behavior in a multilevel public-goods dilemma conducted among samples drawn from the general populations of the United States, Italy, Russia, Argentina, South Africa, and Iran. Results demonstrate that an inclusive social identification with the world community is a meaningful psychological construct that plays a role in motivating cooperation that transcends parochial interests.

The role of attachment in current and future parent caregiving.

Few studies have investigated how attachment bonds between older parents and their adult children influence adult children's provision of care and older parents' seeking of support from kin. The aim of this study was to investigate how the attachment orientations of adult children (N = 119) and older parents (N = 148) predict family caregiving and perceptions of carer burden. Across both samples (that were unrelated), attachment dimensions were associated with current and future caregiving and care receiving and perceptions of carer burden, even when accounting for demographic variables, parental dependence and filial obligation.

Social identity change: shifts in social identity during adolescence.

This study investigated the proposition that adolescence involves significant shifts in social identity as a function of changes in social context and cognitive style. Using an experimental design, we primed either peer or gender identity with a sample of 380 early- (12-13 years), mid- (15-16 years), and late-adolescents (18-20 years) and then measured the effect of the prime on self-stereotyping and ingroup favouritism. The findings showed significant differences in social identity across adolescent groups, in that social identity effects were relatively strong in early- and late-adolescents, particularly when peer group identity rather than gender identity was salient.

Group-based trust in strangers: the role of stereotypes and expectations.

Across two studies, we provide evidence for group-based trust in strangers. Specifically, when we offered participants a choice between an unknown monetary allocation made by an in-group (university or major) or an out-group allocator, both of whom had total control over the distribution of an identical sum of money, participants strongly preferred the in-group allocator. This preference occurred regardless of whether the stereotype of the in-group was relatively more positive or more negative than that of the out-group.

Globalization and human cooperation.

Globalization magnifies the problems that affect all people and that require large-scale human cooperation, for example, the overharvesting of natural resources and human-induced global warming. However, what does globalization imply for the cooperation needed to address such global social dilemmas? Two competing hypotheses are offered. One hypothesis is that globalization prompts reactionary movements that reinforce parochial distinctions among people.

[Effects of direct and indirect exchange on trust of in-group members].

Yamagishi and colleague showed that behavior favoring the in-group and trust of in-group members are based on the expectation of generalized exchange. We successfully tested a related prediction that people show stronger trust of in-group members than of out-group members in the faith game but not in the trust game. We argued that the direct exchange aspect inherent in the trust game suppresses expectations of generalized exchange taking place in the group.