In-group Cooperation Research Articles

Social antagonism, identity-driven beliefs, and loss avoidance: Evidence from Guinea

We use a lab-in-the-field experiment to study identity preferences, other-regarding beliefs, and conflict behavior among the Fulani and Malinke in Guinea, Sub-Saharan Africa. In a hawk-dove game, we explore the existence of out-group hostility and ingroup cooperation compared to the baseline where pairs are uninformed of each other's region of origin. We observe that ethnic identity, especially among the Malinke, encourages loss aversion in situations where negative earnings are possible. Identitydriven beliefs, i.e. expectations of others, lead to either reciprocity among homogeneous pairs or materialism in diverse pairs. Using complementary survey data, we also find that high out-group trust and less linguistic diversity are correlated with conflict avoidance.

The effect of intergroup competition outcome on ingroup cooperation: insights from the male warrior hypothesis

IntroductionThe Male Warrior Hypothesis (MWH) proposes that sex-specific selective pressures have promoted male cooperation with the ingroup members to outcompete rival groups. However, intergroup conflicts do not occur in isolation and the outcomes of previous competitions may influence group cooperativeness. Since this phenomenon is not well understood, we aimed to shed light on the effect of previous competition outcome on later cooperative behavior under intergroup conflicts. Based on the MWH, we hypothesized that repeated contests between groups could enhance ingroup cooperation, regardless of the outcome of the previous contest because status is at risk, but when competition is not present, participants would move to the symmetric equilibria.MethodsTo test this hypothesis, we recruited 246 individuals organized in groups of 6 and measured cooperation using a threshold public good game over two rounds, manipulating the outcome in the first round to create groups of winners and losers.ResultsOur results show that intergroup conflict scenarios promoted cooperation in both victory and defeat conditions, whereas, in the control scenario only losers increased their cooperation.DiscussionWe argue that winners under the presence of an external threat may enhance in-group cooperation in order to assure their status; whereas, losers may be attempting to regain it.

Intergroup competition, group status, and individuals’ cooperation behavior: Evidence from a laboratory experiment

Intergroup competition has been proven to increase ingroup cooperation, but it will also divide individuals into high-status groups and low-status groups, which may lead to group-level conflict and affect cooperation behavior among different status group members. In this paper, we conduct a laboratory experiment to find how group status caused by intergroup competition changes individuals’ cooperation behavior in two representative social dilemma frameworks, the public goods game and the prisoner's dilemma game. Experimental results show that both high-status group members and low-status group members will improve ingroup cooperation, and there exists the framing effect of cooperation which affects different status group members’ decisions under different situations. Specifically, the increase of ingroup cooperation occurs among low-status group members in the public goods game and high-status group members in the prisoner's dilemma game. Besides, we find no evidence of any significant change in outgroup cooperation among different status group members.

Speakers are more cooperative and less individual when interacting in larger group sizes.

Cooperation, acoustically signaled through vocal convergence, is facilitated when group members are more similar. Excessive vocal convergence may, however, weaken individual recognizability. This study aimed to explore whether constraints to convergence can arise in circumstances where interlocutors need to enhance their vocal individuality. Therefore, we tested the effects of group size (3 and 5 interactants) on vocal convergence and individualization in a social communication scenario in which individual recognition by voice is at stake. In an interactive game, players had to recognize each other through their voices while solving a cooperative task online. The vocal similarity was quantified through similarities in speaker i-vectors obtained through probabilistic linear discriminant analysis (PLDA). Speaker recognition performance was measured through the system Equal Error Rate (EER). Vocal similarity between-speakers increased with a larger group size which indicates a higher cooperative vocal behavior. At the same time, there was an increase in EER for the same speakers between the smaller and the larger group size, meaning a decrease in overall recognition performance. The decrease in vocal individualization in the larger group size suggests that ingroup cooperation and social cohesion conveyed through acoustic convergence have priority over individualization in larger groups of unacquainted speakers.

Team Masculinity and Performance: Evidence from Major League Soccer

Abstract: Previous papers provide evidence that psychological characteristics such as personal masculinity are related to performance. Although relationships have been well established on an individual level, there has been little attempt to analyze the performance of teams that diverge in terms of masculinity. This paper studies the impact of team masculinity on its performance, paying particular attention to the connection between masculinity and cooperative behavior within a team. We use data on Major League Soccer teams because sports competitions represent a good ground for demonstrating masculinity and provide open data. Our results suggest a positive connection between the group’s average masculinity and its performance. We test whether this fact can be explained by increased in-group cooperation, first revealed in Stirrat and Perrett’s experimental study (2012) but do not find any relationship. As for the team’s diversity in masculinity, we do not find any impact on team performance.

“Big Gods” in Ancient Mesopotamia

According to the Big Gods Theory, religions with beliefs in moralizing supernatural agents were culturally selected because they enhanced in-group cooperation during intergroup competition and conflict (e.g. Norenzayan 2013). According to the supernatural punishment hypothesis (SPH), this was possible because such agents were culturally represented as punitive and wrathful (e.g. Shariff and Norenzayan 2011). These gods activated reputational concerns, fears of punishment, and social compliance among believers. I examine evidence for the SPH from ancient Mesopotamia based on the cultural evolution of beliefs in the god Marduk. I argue that, contrary to the SPH, Marduk and other ancient Mesopotamian gods were often imagined to be both punitive and benevolent. I examine potential psychological and ecological factors involved in the cultural transmission of beliefs in these supernatural protectors alternative to those proposed by the SPH. I raise general questions concerning collecting and interpreting big data as evidence for Big Gods.

Cooperating with the outgroup rather than the ingroup: The effects of status, individual mobility, and group mobility on resource allocation and trust in an interactional game

We describe a team game that implements a social dilemma between ingroup cooperation and defection by self-enriching outgroup exchange. We test hypotheses derived from social identity theory about how group status and belief about individual mobility and group mobility affect exchange behavior. We ran 60 experimental team games between rich and poor groups under one of four experiment conditions in a fully crossed design, manipulating the presence or absence of individual mobility and group mobility beliefs. Each game was played over 10 rounds in which participants generated wealth for self or group by allocating tokens to either the ingroup or outgroup bank or to outgroup individuals. We identify 10 exchange strategies via latent class analysis and show how class membership and resulting perceptions of group trust are predicted by the experimental conditions. The results show that rich status and individual mobility promote defecting exchanges with outgroup individuals, and that behavior under individual mobility beliefs weakens ingroup trust. In contrast, intergroup competition of the group mobility condition did not affect ingroup cooperation versus defection or trust.

Can Reference to Others’ Behaviour Foster a Cooperative Group in Intergroup Conflict Situations?

This study examined the effect of others’ behaviour on ingroup cooperation in intergroup conflict situations. Following cultural group selection theory, reference to other group members’ behaviour enhances ingroup cooperation in these situations. The validity of the cultural group selection theory was confirmed using an evolutionary simulation and a vignette experiment. However, no empirical study has tested this theory in the lab to assess ingroup cooperative behaviour. Hence, this study conducted an experiment using a repeated public goods game with intergroup conflicts. In total, 132 Japanese undergraduates (54 references, 48 non-references, and 30 controls) participated in this study. Two three-person groups played a public goods game, and the group with the higher number of cooperators received a portion of the other group’s public goods (intergroup conflict). The situation in which participants could refer to the feedback in each game trial was manipulated: reference condition (informed other members’ decisions in a previous trial and the win/loss of intergroup conflict), non-reference condition (informed only win/loss), and control condition (no information). The results validated the hypothesis that ingroup cooperation is enhanced in situations where participants can refer to other members’ behaviour more than in other situations.

Parochial cooperation in wild chimpanzees: a model to explain the evolution of parochial altruism.

Parochial altruism, taking individual costs to benefit the in-group and harm the out-group, has been proposed as one of the mechanisms underlying the human ability of large-scale cooperation. How parochial altruism has evolved remains unclear. In this review paper, we formulate a parochial cooperation model in small-scale groups and examine the model in wild chimpanzees. As suggested for human parochial altruism, we review evidence that the oxytocinergic system and in-group cooperation and cohesion during out-group threat are integral parts of chimpanzee collective action during intergroup competition. We expand this model by suggesting that chimpanzee parochial cooperation is supported by the social structure of chimpanzee groups which enables repeated interaction history and established social ties between co-operators. We discuss in detail the role of the oxytocinergic system in supporting parochial cooperation, a pathway that appears integral already in chimpanzees. The reviewed evidence suggests that prerequisites of human parochial altruism were probably present in the last common ancestor between Pan and Homo.This article is part of the theme issue ‘Intergroup conflict across taxa’.

Moralizing gods, local gods, and complexity in Hindu god concepts: evidence from South India

ABSTRACT Cultural evolutionary approaches to religion have found that in small-scale societies, “local gods” (LGs) usually care about ritual, in-group cooperation, and ecological challenges, whereas in large-scale societies, “moralizing gods” (MGs) are more concerned with prosociality. In contrast, Hindu deities are considered aspects of one god, and urban regions include LGs, complicating the prevailing distinction. The current study investigated perceptions of deities in Mysore, India, among Hindus (N = 165) who primarily worship Shiva, a prototypical MG, and Chamundeshwari, the LG. Using surveys and experimental games, our results indicated that Chamundeshwari is perceived as possessing characteristics typical of both LGs and MGs. Furthermore, beliefs about Shiva as a moralizing and punitive god were associated with prosocial game allocations in three experimental economic games, but similar beliefs about Chamundeshwari were not. Participation in rituals for Shiva predicted allocations toward outgroup members in one game, whereas participation in rituals for Chamundeshwari predicted selfish allocations in one game. These mixed results demonstrate the challenges that demographic and cultural variation can impose on dichotomous models of deities to explain religious variation, and we offer directions for future research to better understand such complexity.

Psychological mechanisms of ingroup cooperation among real groups and salience of intergroup situation

Psychological mechanisms of ingroup cooperation among real groups and salience of intergroup situation

Cooperation between newcomers and incumbents: The role of normative disagreements

Cooperation in groups often requires individual members to make costly contributions that benefit the group as a whole. Prior research suggests that shared norms can help to support ingroup cooperation by prescribing common standards of how much to contribute. These common standards may be disrupted when groups undergo membership change, i.e., when members from outgroups enter the ingroup. When newcomers and incumbents have different notions about how much to contribute, a normative disagreement ensues that could undermine cooperation and the extent to which individuals identify with the group. In a laboratory experiment, we manipulate whether newcomers and incumbents disagree about how much to contribute in a public goods game with peer punishment. We examine whether normative disagreement between newcomers and incumbents affects newcomer-incumbent relations in terms of group identification, the emergence of a social norm, and costly punishment. The main goal is to test whether normative disagreement and the resulting newcomer-incumbent relations harm cooperation in terms of contributions to the common good. We find that normative disagreement between newcomers and incumbents negatively affects the emergence of a shared social norm and lowers feelings of group identification. Contrary to expectations, normative disagreement does not affect cooperation negatively. Instead, participants adjust their behavior to each other’s standards, using punishment for norm enforcement. This punishment is especially directed at low-contributing newcomers, leading them to conform to the incumbents’ higher contribution standards.

Ingroup cooperation among Japanese baseball fans using the one-shot prisoner’s dilemma game

ABSTRACT This study aimed to examine the external validity of social identity theory (SIT) and the bounded generalised reciprocity hypothesis (BGR) to generate ingroup cooperation in real groups. Previous research has demonstrated the existence of ingroup cooperation predicted by both theories in the minimal group, whereas neither theory was supported in real groups. However, ingroup cooperation predicted by both theories was revealed among Japanese baseball fans after controlling for confounding factors. Furthermore, previous research showed that ingroup cooperation was better explained by the BGR than by the SIT when the cost of cooperation was high. The limitation of these studies is that ingroup cooperation was measured in terms of behavioural intention (a vignette experiment). This study employed a one-shot prisoner’s dilemma game to measure ingroup cooperation among Japanese baseball fans. The results supported only BGR in that ingroup cooperation was enhanced in situations wherein participants could expect a reciprocal relationship with their game partner.

Does Whistleblowing on Tax Evaders Reduce Ingroup Cooperation?

Whistleblowing is a powerful and rather inexpensive instrument to deter tax evasion. Despite the deterrent effects on tax evasion, whistleblowing can reduce trust and undermine agents’ attitude to cooperate with group members. Yet, no study has investigated the potential spillover effects of whistleblowing on ingroup cooperation. This paper reports results of a laboratory experiment in which subjects participate in two consecutive phases in unchanging groups: a tax evasion game, followed by a generalized gift exchange game. Two dimensions are manipulated in our experiment: the inclusion of a whistleblowing stage in which, after observing others’ declared incomes, subjects can signal other group members to the tax authority, and the provision of information about the content of the second phase before the tax evasion game is played. Our results show that whistleblowing is effective in both curbing tax evasion and improving the precision of tax auditing. Moreover, we detect no statistically significant spillover effects of whistleblowing on ingroup cooperation in the subsequent generalized gift exchange game, with this result being unaffected by the provision of information about the experimental task in the second phase. Finally, the provision of information does not significantly alter subjects’ (tax and whistleblowing) choices in the tax evasion game: thus, knowledge about perspective ingroup cooperation did not alter attitude toward whistleblowing.

Pathogen Threat and In-group Cooperation.

Disease-causing parasites and pathogens play a pivotal role in intergroup behavior. Previous studies have suggested that the selection pressure posed by pathogen threat has resulted in in-group assortative sociality, including xenophobia and in-group favoritism. While the current literature has collated numerous studies on the former, strikingly, there has not been much research on the relationship between pathogen threat and in-group cooperation. Drawing upon prior studies on the function of the behavioral immune system (BIS), we argued that the BIS might facilitate cooperation with in-group members as a reactive behavioral immune response to pathogen threat. More specifically, we held that individuals might utilize cooperative behavior to ensure that they can receive social support when they have contracted an infectious disease. We reviewed existing findings pertaining to the potential role of the BIS in in-group cooperation and discussed directions for future studies.

Intergroup Discrimination in Cooperation Among Moral and Non-Moral Groups

In-group favouritism is ubiquitous and previous studies have consistently found that individuals cooperate more with in-group members than out-group members in diverse contexts. Yet, there has not been much research on the role of the nature of groups in intergroup cooperation. A recent study found stronger levels of in-group favouritism amongst groups formed on the basis of shared moral values. However, it remained unclear whether the increased favouritism was caused by a greater tendency to act favourably towards the in-group or derogatorily towards the out-group. The present study thus investigated intergroup cooperation among morality-based and non-morality-based groups and examined the levels of cooperation with an in-group member and an out-group member as compared to a person whose group membership was unknown. Regardless of how groups were formed, in-group favouritism was present, while out-group derogation was absent. Furthermore, we found that the shared morality promoted in-group cooperation indirectly via low perceived out-group warmth. Our study provides further evidence that in-group favouring behaviour does not include derogating out-groups and points to the importance of further investigation into the role of the shared morality in intergroup cooperation.

Cooperation in a fragmented society: Experimental evidence on Syrian refugees and natives in Lebanon

Lebanon is the country with the highest density of refugees in the world, raising the question of whether the host and refugee populations can cooperate harmoniously. We conduct a lab-in-the-field experiment in Lebanon studying intra- and inter-group behavior of Syrian refugees and Lebanese nationals in a repeated public goods game without and with punishment. We randomly assign participants to Lebanese-only, Syrian-only, or mixed sessions. We find that randomly formed pairs in homogeneous sessions, on average, contribute and punish significantly more than those in mixed sessions, suggesting in-group cooperation is stronger. These patterns are driven by Lebanese participants. Further analysis indicates that behavior in mixed groups is more strongly conditioned on expectations about the partner's cooperation than in homogeneous groups.

Public good provision, in-group cooperation and out-group descriptive norms: A lab experiment

We use a public good experiment to study how in-group cooperation is affected by payoff-irrelevant information about cooperation in other groups (i.e., descriptive out-group feedback). We find that positive out-group feedback, indicating above-average cooperation, deters low in-group contributors from increasing their contribution towards the in-group average. By contrast, negative out-group feedback, which informs participants about below-average cooperation, deters high in-group contributors from decreasing their contribution towards the in-group average. These two effects work together to dampen contribution patterns associated with conditional cooperation. Further, we show that the effects are stronger for individual-level feedback (comparing individual contributions with the out-group average) than for group-level feedback (comparing total contributions by in-group members with that of other groups). Interestingly, when allowed to avoid out-group feedback information, the propensity to consult the feedback is similar for high and low in-group contributors, suggesting that information acquisition is not always self-serving.

Does Whistleblowing on Tax Evaders Reduce Ingroup Cooperation?

Whistleblowing is a powerful and rather inexpensive instrument to contrast tax evasion. Despite the deterrent effects on tax evasion, whistleblowing can reduce trust and undermine agents’ attitude to cooperate with group members. Yet, no study has investigated the potential spillover effects of whistleblowing on ingroup cooperation. This paper reports results of a laboratory experiment in which subjects participate in two consecutive phases in unchanging groups: a tax evasion game, followed by a generalized gift exchange game. Two dimensions are manipulated in our experiment: the inclusion of a whistleblowing stage in which, after observing others’ declared incomes, subjects can signal other group members to the tax authority, and the provision of information about the content of the second phase before the tax evasion game is played. Our results show that whistleblowing is effective in both curbing tax evasion and improving the precision of tax auditing. Moreover, we detect no statistically significant spillover effects of whistleblowing on ingroup cooperation in the subsequent generalized gift exchange game, with this result being unaffected by the provision of information about the experimental task in the second phase. Finally, the provision of information does not significantly alter subjects’ (tax and whistleblowing) choices in the tax evasion game: thus, knowledge about perspective ingroup cooperation did not alter attitude towards whistleblowing.

Mothers, Fathers, and Others: Competition and Cooperation in the Aftermath of Conflict

We investigate the possibility that females and males had a distinct path in the evolution of prosociality and competitiveness. We collected experimental data measuring preferences for individual competition and in-group cooperation for a randomly selected sample of 751 individuals in Sierra Leone (aged 18-85) to contrast the behavioural consequences of victimization during the 1991-2003 civil war across gender and parental roles. Our data shows that conflict exposure, in general, tames competitive tendencies, but has the opposite effect for mothers. Victimization increases egalitarianism towards the in-group among non-parents, especially for non-parent males, who are the least egalitarian to start with. Our results imply that the behavioural consequences of conflict close sex and parental gaps in behavioural preferences. To the extent that group harmony may be enhanced by more equal in-group outcomes and more homogenous preferences, these results further lend credence to the idea that the behavioural effects of conflict prime individuals towards group survival. It also suggests that escaping perils and the harshness of resource constraints enables group differences in pro-social preferences (across genders and parental status) that may be detrimental to group harmony and group survival, a fate perhaps currently affecting societies with rising trends of inequality and polarization.