Biomedical subjects

Tom Postmes

Publications and source records attributed to Tom Postmes.

6 recordsLinked to original sources

PubMed2006

Social identity and the recognition of creativity in groups.

This paper develops an analysis of creativity that is informed by the social identity approach. Two studies are reported that support this analysis. Study 1 (N=73) manipulated social identity salience and the content of group norms. The group norm was either conservative (i.e. promoted no change) or progressive (i.e. promoted change). When social identity was salient and the group norm was conservative, a non-novel proposal was perceived to be more creative. Study 2 (N=63) manipulated social norms and identity relevance. Results showed that while social norms influenced perceptions of creativity, identity relevance influenced positivity but not perceptions of creativity. These findings support the idea that perceptions of creativity are grounded in the normative content of group membership and self-categorization processes.

Adolescent↗

PubMed2005

Individuality and social influence in groups: inductive and deductive routes to group identity.

A distinction between forms of social identity formation in small interactive groups is investigated. In groups in which a common identity is available or given, norms for individual behavior may be deduced from group properties (deductive identity). In groups in which interpersonal relations are central, a group identity may also be induced from individual group members' contributions, making individuality and individual distinctiveness a defining feature of the group (inductive identity). Two studies examined the prediction that depersonalization produced by anonymity has opposite effects for groups in which social identity has been induced or deduced. Results confirmed the prediction that depersonalization increases social influence in groups whose identity was more deductive. In contrast, depersonalization decreases social influence in inductive identity groups. Implications for the role of social identity in small groups are discussed. ((c) 2005 APA, all rights reserved).

Adult↗

PubMed2005

Why are modern families small? Toward an evolutionary and cultural explanation for the demographic transition.

As societies modernize, they go through what has become known as "the demographic transition;" couples begin to limit the size of their families. Models to explain this change assume that reproductive behavior is either under individual control or under social control. The evidence that social influence plays a role in the control of reproduction is strong, but the models cannot adequately explain why the development of small family norms always accompanies modernization. We suggest that the widening of social networks, which has been found to occur with modernization, is sufficient to explain the change in reproductive norms if it is assumed that (a) advice and comment on reproduction that passes among kin is more likely to encourage the creation of families than that which passes among nonkin and (b) this advice and comment influence the social norms induced from the communications. This would, through a process of cultural evolution, lead to the development of norms that make it increasingly difficult to have large families.

Biological Evolution↗

PubMed2004

Intergroup distinctiveness and differentiation: a meta-analytic integration.

The authors examined the relation between perceptions of intergroup distinctiveness and intergroup differentiation in a meta-analysis. They tested the social identity theory prediction that low intergroup distinctiveness underlies differentiation (the "reactive distinctiveness" hypothesis) for effects on behavioral and judgmental differentiation. In addition, they examined the moderating power of 4 variables that H. Tajfel and J. C. Turner (1979) predicted would influence differentiation (group identification, relevance of the dimension of comparison, relevance of the outgroup. and nature of intergroup relations). Analysis of 60 tests revealed that the overall effect of distinctiveness on differentiation was not significantly different from 0, but reactive distinctiveness was found on behavioral differentiation measures, whereas reflective distinctiveness was found on judgmental differentiation measures. Only group identification was a reliable moderator. High identifiers showed reactive distinctiveness, whereas low identifiers showed reflective distinctiveness.

Group Processes↗

PubMed2002

Influence of long-term racial environmental composition on subjective well-being in African Americans.

Two studies (N = 126, N = 114) of African Americans supported a model predicting that more racially segregated life contexts are associated with feelings of acceptance by other in-group members and, to a lesser extent, rejection by out-group members. In-group acceptance and out-group rejection in turn influenced identification with the in-group, which was a strong predictor of psychological well-being. Alternative models were not supported. Results suggest that environments that are segregated offer in-group support and acceptance, thereby protecting self-esteem against possible perils of rejection by a powerful out-group. Findings suggest that the improvement of intergroup relations should not be at the expense of intragroup relations.

Adaptation, Psychological↗

PubMed2002

Cognitive and strategic processes in small groups: effects of anonymity of the self and anonymity of the group on social influence.

Two studies examined cognitive and strategic processes of social influence in small groups. A first study showed that anonymity of in-group members to the self cognitively enhanced the perceived unity or entitativity of the group, while the interpersonal attraction to group members decreased. A second study showed that anonymity of the self to the group strategically enhanced differentiation from the group on non-normative dimensions. Overall, it was found that strategic and cognitive processes interact to produce social influence within the group. Implications for theories of social influence in groups are discussed.

Adult↗