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Homophily in the Digital World: A LiveJournal Case Study
March/April 2010 (vol. 14 no. 2)
pp. 15-23
Hady W. Lauw, Search Labs, Microsoft Research
John C. Shafer, Search Labs, Microsoft Research
Rakesh Agrawal, Search Labs, Microsoft Research
Alexandros Ntoulas, Search Labs, Microsoft Research
Are two users more likely to be friends if they share common interests? Are two users more likely to share common interests if they're friends? The authors study the phenomenon of homophily in the digital world by answering these central questions. Unlike the physical world, the digital world doesn't impose any geographic or organizational constraints on friendships. So, although online friends might share common interests, a priori there's no reason to believe that two users with common interests are more likely to be friends. Using data from LiveJournal, the authors show that the answer to both questions is yes.

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Index Terms:
homophily, friendship, interest, social network, Internet
Hady W. Lauw, John C. Shafer, Rakesh Agrawal, Alexandros Ntoulas, "Homophily in the Digital World: A LiveJournal Case Study," IEEE Internet Computing, vol. 14, no. 2, pp. 15-23, March-April 2010, doi:10.1109/MIC.2010.25
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