Leaving us in tiers: can homophily be used to generate tiering effects?

  • Brian R. HirshmanEmail author
  • Jesse St. Charles
  • Kathleen M. Carley


Substantial evidence indicates that our social networks are divided into tiers in which people have a few very close social support group, a larger set of friends, and a much larger number of relatively distant acquaintances. Because homophily—the principle that like seeks like—has been suggested as a mechanism by which people interact, it may also provide a mechanism that generates such frequencies and distributions. However, our multi-agent simulation tool, Construct, suggests that a slight supplement to a knowledge homophily model—the inclusion of several highly salient personal facts that are infrequently shared—can more successfully lead to the tiering behavior often observed in human networks than a simplistic homophily model. Our findings imply that homophily on both general and personal facts is necessary in order to achieve realistic frequencies of interaction and distributions of interaction partners. Implications of the model are discussed, and recommendations are provided for simulation designers seeking to use homophily models to explain human interaction patterns.


Homophily Social group size Tiering Agent-based simulation Dynamic network analysis 


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Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  • Brian R. Hirshman
    • 1
    Email author
  • Jesse St. Charles
    • 1
  • Kathleen M. Carley
    • 1
  1. 1.Computation, Organization and Society Program, School of Computer ScienceCarnegie Mellon UniversityPittsburghUSA

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