Birds of Different Feathers Cooperate Together: No Evidence for Altruism Homophily in Networks

Abstract

Many evolutionary models of cooperation assume that altruists possess telltale signs of disposition that they use to find and selectively associate with each other. Prior research finds that people can detect these signs of altruism in strangers, but we do not yet know whether this results in altruism homophily. We argue that dispositions should matter less in repeated interactions, where behavior is based on reciprocity. As a consequence, we should not expect people to have accurate insight into the dispositions (egoism vs. altruism) of their friends, nor should we expect these relations to be characterized by altruism homophily. Three studies, employing diverse methodologies and measures, find no evidence of altruism homophily. Moreover, we find that people have poor insight into their friends' altruism. We discuss the implications of these findings for the emergence of altruism and the role of embedded interactions in sustaining human cooperation.

Predicting Altruistic Behavior and Assessing Homophily: Evidence from the Sisterhood

“…Investigation into the existence of altruism homophily in social groups has likewise been limited. Only two studies, Pradel et al (2009) and Simpson et al (2014), have investigated both questions. The results of those studies appear to be diametrically opposed.…”

“…Van Lange, Klapwijk, and Van Munster (2011) found that the anticipation of future interaction causes egoists to act more prosocially. Simpson et al (2014) argued that an underlying reciprocity approach to explaining prosocial behavior will lead to two very different outcomes than those predicted by Pradel et al (2009). First, because the expectation of a long-term relationship will trump the significance of dispositional altruism (Parks and Rumble 2001;Rusbult and Van Lange 2003;Van Lange et al 2011), widespread altruism homophily will not be manifested in the general population.…”

“…Individuals may project their own disposition onto their friends' behavior (Ross, Greene, and House 1977;Krueger and Clement 1994;Fetchenhauer and Dunning 2006;Simpson and Willer 2008), with the result being that individuals have limited insight into the dispositional altruism of their friends. Simpson et al (2014) conducted three studies to test their hypotheses: (1) friendships will exhibit altruism homophily, and (2) individuals are able to predict their friends' prosociality towards strangers. In their first study, students were sent email invitations and upon agreeing to participate by completing a survey were asked to invite additional participants (respondent-driven sample) with whom they had regular contact.…”

Cultural legacies and political preferences: the failure of separatism in the Swiss Jura

“…For example, the greater the distance from a center to its peripheries, "the greater the risk that these will become the nuclei of independent center formation" (Rokkan and Urwin, 1983, p. 16), hence the looser the bonds that tie the two together and the more likely secession is to occur. Whatever their origin may be, social networks may promote in-group altruism that fosters collective action (but see Simpson et al, 2014 for some disconfirming evidence).…”

“…Roccas and Brewer, 2002;Simmel, 1955), this practice is questionable and the assumption of cultural differences that matter politically must itself be explained (Posner, 2004). Moreover, the mechanism of cultural homophily (McPherson, Smith-Lovin and Cook, 2001;Simpson et al, 2014) may not be the only, or the most important, reason for the political effects of cultural identities: to have an effect, cleavages also need to be activated by political entrepreneurs (Lipset and Rokkan, 1967;Rokkan and Urwin, 1983).…”