Diversity and Popularity in Social Networks

Homophily, the tendency of linked agents to have similar characteristics, is an important feature of social networks. We present a new model of network formation that allows the linking process to depend on individuals types and study the impact of such a bias on the network structure. Our main results fall into three categories: (i) we compare the distributions of intra- and inter-group links in terms of stochastic dominance, (ii) we show how, at the group level, homophily depends on the groups size and the details of the formation process, and (iii) we understand precisely the determinants of local homophily at the individual level. Especially, we find that popular individuals have more diverse networks. Our results are supported empirically in the AddHealth data looking at networks of social connections between boys and girls.

[1]  M. Newman.  Coauthorship networks and patterns of scientific collaboration , 2004, Proceedings of the National Academy of Sciences of the United States of America.

[2]  Timothy G. Conley,et al.  Social Learning Through Networks: The Adoption of New Agricultural Technologies in Ghana , 2001 .

[3]  M. McPherson,et al.  BIRDS OF A FEATHER: Homophily , 2001 .

[4]  Matthew O. Jackson,et al.  Average Distance, Diameter, and Clustering in Social Networks with Homophily , 2008, WINE.

[5]  M. Jackson,et al.  An Economic Model of Friendship: Homophily, Minorities and Segregation , 2007 .

[6]  Matthew O. Jackson,et al.  How Homophily Affects Communication in Networks , 2008 .

[7]  Paolo Pin.  Four multi-agents economic models: From evolutionary competition to social interaction , 2009 .

[8]  Marcel Fafchamps,et al.  Risk Sharing Networks in Rural Philippines , 1997 .

[9]  N. Christakis,et al.  SUPPLEMENTARY ONLINE MATERIAL FOR: The Collective Dynamics of Smoking in a Large Social Network , 2022 .

[10]  Ralph Stinebrickner,et al.  Interracial Friendships in College , 2010, Journal of Labor Economics.

[11]  Timothy G. Conley,et al.  Learning About a New Technology: Pineapple in Ghana , 2010 .

[12]  Steven L. Puller,et al.  The Old Boy (and Girl) Network: Social Network Formation on University Campuses , 2008 .

[13]  Anne Boschini,et al.  Is Team Formation Gender Neutral? Evidence from Coauthorship Patterns , 2007, Journal of Labor Economics.

[14]  E. Laumann,et al.  Racial/ethnic group differences in the prevalence of sexually transmitted diseases in the United States: a network explanation. , 1999, Sexually transmitted diseases.

[15]  Mark E. J. Newman,et al.  The Structure and Function of Complex Networks , 2003, SIAM Rev..

[16]  M. Jackson,et al.  The Effects of Social Networks on Employment and Inequality , 2004 .

[17]  Duncan J. Watts,et al.  Collective dynamics of ‘small-world’ networks , 1998, Nature.

[18]  Albert,et al.  Emergence of scaling in random networks , 1999, Science.

[19]  J. Coleman.  Relational Analysis: The Study of Social Organizations with Survey Methods , 1958 .

[20]  Rachel Kranton,et al.  Risk-Sharing Networks , 2005 .

[21]  Brian W. Rogers,et al.  Meeting Strangers and Friends of Friends: How Random are Social Networks? , 2007 .

[22]  Lori Beaman,et al.  Social Networks and the Dynamics of Labor Market Outcomes: Evidence from Refugees ¤ , 2008 .

[23]  J. Montgomery.  Social Networks and Labor-Market Outcomes: Toward an Economic Analysis , 1991 .

[24]  P. Lazarsfeld,et al.  Friendship as Social process: a substantive and methodological analysis , 1964 .

[25]  M. McPherson,et al.  Birds of a Feather: Homophily in Social Networks , 2001 .

[26]  F. Chung,et al.  The average distances in random graphs with given expected degrees , 2002, Proceedings of the National Academy of Sciences of the United States of America.