Skip to main content

08.03 Identities and Networks #1: social mechanisms linking group identities, social network structures and sustainable cooperation

| Projects

Aim of the project

A key threat to sustainable cooperation in a diverse population are boundaries between subgroups. Such boundaries can arise from exclusive subgroup identities, segregated social networks, or both. This project studies how and under which conditions it is possible that inclusive subgroup identities and social relations cutting across subgroup boundaries can become mutually reinforcing, sustaining cooperation that goes beyond those boundaries.

Theoretical background

Many societal challenges require sustained joint efforts by members from different subgroups of a diverse population. Effective policies to address climate change or successful integration of migrants are but two examples of common goods benefitting all members of society, which are harder to bring about when subgroup boundaries cloud the view on overarching interests.

Two important boundaries between subgroups are exclusive subgroup identities and segregated social networks (i.e. a lack of positive interpersonal relations cutting across subgroup boundaries). Exclusive subgroup identities may lead to ingroup-favoritism, impeding investments in a common good which benefits also outgroup members (Iyengar et al 2019). Segregated social networks can be a problem because a lack of intergroup social contact may promote negative views of the outgroup or wrong or biased beliefs regarding outgroup members’ interest in a common good (Vasconcelos et al 2021). 

Interpersonal network relations, like friendships, which cut across subgroup boundaries can support contribution to common efforts which benefit members of multiple subgroups (Vasconcelos et al 2021). Moreover, people having more interpersonal relations across subgroup boundaries may identify less strongly with their own subgroup (Leszczensky & Pink 2019; Leszczensky et al 2016) and hold more positive views of outgroups. Yet, it remains unclear under which conditions intergroup social relations and inclusive subgroup identities also sustain cooperation between members of different groups.

To disentangle the complex interplay of network relations, subgroup identification, and cooperation in a diverse population, the project will proceed in two steps. In the first step, we focus on cooperation at the interpersonal level. Examples are cooperation between individuals from different subgroups, e.g. different ethnic groups, in tasks like doing joint homework in a school class or providing practical or emotional support to peers. For this, we will extend research on the co-evolution of social network relations, intergroup attitudes and ethnic identification in multi-ethnic classrooms (Leszczensky & Pink 2019; Leszczensky et al 2016). We draw on theories connecting social influence and social identity (Spears 2021) to further develop and test empirically hypotheses about the link between various forms of interpersonal cooperation among members from different ethnic groups, their cross-group relations, and their more inclusive subgroup identification. A particular focus will be on the question how the position of high- and low identifiers in an evolving network structure affects the prospects for cooperation across subgroup boundaries to become more common over time.

In the second step, we utilize insights from this work to study cooperation in the provision of common goods that stretches beyond the interpersonal level, focusing on the role of social relations in sustaining contributions to such common goods (Flache et al, 2017). A key question here will be under which conditions people are willing to contribute to common goods benefitting also other subgroups, or prefer to invest in common goods fostering mainly interests of their own subgroup at the cost of a societally less desirable result. Drawing on insights about the role of high- vs. low identifiers obtained in the network studies, we will develop and test in controlled lab or online experiments hypotheses about the effects of the location of high- and low identifiers in a network on such decisions. Which constellations are most conducive for sustaining a virtuous circle of increasingly less exclusive subgroup identities, more integrated networks, and cooperation to achieve a common good benefitting all subgroups rather than only the own subgroup?

This project highlights the role of network-structure and network-dynamics (e.g. homophily as driver of network change) for the link between social identity, networks and cooperation. The sister project (8.4) based in social psychology, focuses more on the underlying social psychological mechanisms of, for example, homophily based on common identities.

Research design

This research will involve the analysis of field data about the co-evolution of social relations, subgroup identification, and interpersonal cooperation in multiethnic classrooms, as well as experimental lab studies. Existing field data stem from several large-scale longitudinal survey studies measuring complete networks of friendship relations as well as indicators of ethnic group identification and interpersonal cooperation in classroom settings (TASS, CILS4EU, FIS). Experimental studies will build on the paradigm of public-good games with additional interpersonal interaction and network relations between participants  (e.g. Flache et al, 2017; Vasconcelos et al, 2021). This PhD project will be based in the department of Sociology, RuG, and conducted in close interaction with a SCOOP sister-project focusing on the psychological mechanisms connecting social identity, social relations and cooperation, which is located in the department of Social Psychology (RuG). Andreas Flache and Russell Spears are involved in the supervision of both projects.

It is desirable that the PhD candidate has already some expertise in at least one of the two main methods applied (social network analysis, experiments with public good games).

Partner project: 08.04 Identities and Networks #2: How psychological processes relating to social identities and social networks interact to sustain cooperation

  • Discipline
    Sociology, Social Psychology
  • Location
    University of Groningen, Faculty of Behavioral and Social Sciences, Department of Sociology


Flache, A., Bakker, D.M., Mäs, M. & Dijkstra, J. 2017. “The Double Edge of Counter–Sanctions. Is Peer Sanctioning Robust to Counter–Punishment but Vulnerable to Counter–Reward?” In: Ben Jann, Wojtek Przepiorka (Eds.). Social Dilemmas, Institutions, and the Evolution of Cooperation. De Gruyter / Oldenbourg. ISBN 978-3-11-047195-3.

Iyengar, S., Lelkes, Y., Levendusky, M., Malhotra, N., & Westwood, S. J. (2019). The origins and consequences of affective polarization in the United States. Annual Review of Political Science, 22, 129-146.

Leszczensky L, Pink S. 2019. What Drives Ethnic Homophily? A Relational Approach on How Ethnic Identification Moderates Preferences for Same-Ethnic Friends. American Sociological Review 84(3):394-419. doi:10.1177/0003122419846849

Leszczensky, L., Stark, T.H., Flache, A., Munniksma, A. 2016. Disentangling the Relationship between Young Immigrants' National Identification and their Friendships with Natives. Social Networks, 44, 179–189.

Spears, R. 2021. Social Influence and Group Identity. Annu. Rev. Psychol. 2021. 72:367–90

Vasconcelos, V. V., S. M. Constantino, A. Dannenberg, M. Lumkowsky, E. Weber, & S. Levin. 2021. Segregation and clustering of preferences erode socially beneficial coordination. PNAS December 14, 2021 118 (50) e2102153118;