Using Social Network Methods to Test for Assortment of Prosociality among Korean High School Students.
Assortative interaction among altruistic individuals is a necessary condition for the evolution of cooperation. The requirement for assortment holds regardless of whether a meta-population is subdivided into distinct and isolated subgroups or has ephemeral boundaries with a high migration rate. The assumption, however, is rarely tested directly. In this paper, we develop a method to test for assortment of prosociality in network-structured data. The method is applied to a friendship network collected from 238 Korean students attending the same high school. A mixing matrix was used to explore the presence of assortative friendship among more prosocial individuals. An exponential random graph model of network structure that accounts for additional observed relational propensities (higher-than-expected number of people nominating no friends) and sampling constraints (upper bound on friendship nominations) found that individual prosociality predicted friendship propensity, and that individuals with higher prosocial scores had a higher probability of befriending other more prosocial individuals. The results reveal that a considerable level of assortment of prosociality characterizes this population.
Institute of Cross-Cultural Studies, Seoul National University, Seoul, South Korea.
Jun-Hong
JH
Kim
Department of Anthropology, University of Washington, Seattle, WA, United States of America; Center for Statistics and the Social Sciences, University of Washington, Seattle, WA, United States of America; Center for Studies in Demography and Ecology, University of Washington, Seattle, WA, United States of America.
Darryl J
DJ
Holman
Department of Anthropology, University of Washington, Seattle, WA, United States of America; Center for Statistics and the Social Sciences, University of Washington, Seattle, WA, United States of America; Center for Studies in Demography and Ecology, University of Washington, Seattle, WA, United States of America.
Steven M
SM
Goodreau
D000533:Altruism; D005260:Female; D033062:Friends / Q000523:psychology*; D006608:Hierarchy, Social; D006801:Humans; D008297:Male; D008962:Models, Theoretical; D010379:Peer Group; D056910:Republic of Korea; D012919:Social Behavior; D012944:Social Support; D013334:Students / Q000523:psychology*