Social Groups and Social Network Formation

51 Pages Posted: 20 Dec 2014 Last revised: 19 Nov 2015

Bassel Tarbush

University of Oxford - Merton College

Alexander Teytelboym

University of Oxford - Institute for New Economic Thinking at the Oxford Martin School

Date Written: September 2, 2015

Abstract

We present a dynamic model of social network formation in which a fixed number of agents interact in overlapping social groups. We derive several results on the formation of links in such networks, including results on the degree distribution, on comparative statics relating degree and group size, and on the dynamics of homophily. In particular, we derive comparative statics showing that degree is typically positively related to social group size but negatively related to the size of the overlap across multiple social groups. This is supported by evidence from a Facebook dataset. We also show that homophily over an agent’s lifespan in the network can be non-monotonic, reaching a global maximum in some period before eventually decreasing.

Keywords: social groups, dynamic network formation, social networks, homophily

JEL Classification: D85, A14, Z13

Suggested Citation

Tarbush, Bassel and Teytelboym, Alexander, Social Groups and Social Network Formation (September 2, 2015). Games and Economic Behavior, Forthcoming. Available at SSRN: https://ssrn.com/abstract=2456532 or http://dx.doi.org/10.2139/ssrn.2456532

Bassel Tarbush (Contact Author)

University of Oxford - Merton College ( email )

Merton College
Oxford, OX1 4JD
United Kingdom

Alexander Teytelboym

University of Oxford - Institute for New Economic Thinking at the Oxford Martin School ( email )

Eagle House
Walton Well Road
Oxford, OX2 6ED
United Kingdom

Paper statistics

Downloads
162
Rank
151,115
Abstract Views
677