title: Purity homophily in social networks.
abstract: Does sharing moral values encourage people to connect and form communities? The importance of moral homophily (love of same) has been recognized by social scientists, but the types of moral similarities that drive this phenomenon are still unknown. Using both large-scale, observational social-media analyses and behavioral lab experiments, the authors investigated which types of moral similarities influence tie formations. Analysis of a corpus of over 700,000 tweets revealed that the distance between 2 people in a social-network can be predicted based on differences in the moral purity content-but not other moral content-of their messages. The authors replicated this finding by experimentally manipulating perceived moral difference (Study 2) and similarity (Study 3) in the lab and demonstrating that purity differences play a significant role in social distancing. These results indicate that social network processes reflect moral selection, and both online and offline differences in moral purity concerns are particularly predictive of social distance. This research is an attempt to study morality indirectly using an observational big-data study complemented with 2 confirmatory behavioral experiments carried out using traditional social-psychology methodology.
authors.affiliation: Psychology Department, Brain and Creativity Institute, University of Southern California.
authors.forename: Morteza
authors.initials: M
authors.lastname: Dehghani
authors.affiliation: Psychology Department, University of Southern California.
authors.forename: Kate
authors.initials: K
authors.lastname: Johnson
authors.affiliation: Psychology Department, University of Southern California.
authors.forename: Joe
authors.initials: J
authors.lastname: Hoover
authors.affiliation: Kellogg School of Business, Northwestern University.
authors.forename: Eyal
authors.initials: E
authors.lastname: Sagi
authors.affiliation: Brain and Creativity Institute and Computer Science Department, University of Southern California.
authors.forename: Justin
authors.initials: J
authors.lastname: Garten
authors.affiliation: Computer Science Department, University of Southern California.
authors.forename: Niki Jitendra
authors.initials: NJ
authors.lastname: Parmar
authors.affiliation: Sociology Department, Duke University.
authors.forename: Stephen
authors.initials: S
authors.lastname: Vaisey
authors.affiliation: Ford School of Public Policy, University of Michigan.
authors.forename: Rumen
authors.initials: R
authors.lastname: Iliev
authors.affiliation: Psychology Department, University of Southern California.
authors.forename: Jesse
authors.initials: J
authors.lastname: Graham
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D009014:Morals; D012929:Psychological Distance; D060756:Social Networking