From Santa Fe Institute Events Wiki
Is There a Physics of Society? January 10-12, 2008, Santa Fe NM
Friday, January 12, 2008
3:10 - 3:50 Matthew O. Jackson (homepage)
An Economic Model of Friendships: Understanding the Roles of Choice and Chance in Social Network Formation
Both opportunity and preferences matter in social network formation. By examining an economic model of friendship formation that incorporates both choice in which relationships to form and chance meetings, we can sort out the relative roles of these two factors in determining social network structure. The model is used to understand three empirical patterns of friendship formation across different racial groups in U.S. high schools: (i) larger groups tend to form more same-race friendships and fewer cross-race friendships than small groups, (ii) larger groups form more friendships per capita, and (iii) the most extreme bias towards own-race friendships is exhibited by middle-sized groups. It is shown that these empirical observations can sorted according to whether they are driven by choice or chance.