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Homophily, group size, and the diffusion of political information in social networks: Evidence from Twitter


  • Halberstam, Yosh
  • Knight, Brian


We investigate the role of homophily – a tendency to interact with similar individuals–in the diffusion of political information in social networks. We develop a model predicting disproportionate exposure to like-minded information and that larger groups have more connections and are exposed to more information. To test these hypotheses, we use data on links and communications between politically-engaged Twitter users. We find that users affiliated with majority political groups, relative to the minority group, have more connections, are exposed to more information, and are exposed to information more quickly. Likewise, we find that users are disproportionately exposed to like-minded information and that information reaches like-minded users more quickly.

Suggested Citation

  • Halberstam, Yosh & Knight, Brian, 2016. "Homophily, group size, and the diffusion of political information in social networks: Evidence from Twitter," Journal of Public Economics, Elsevier, vol. 143(C), pages 73-88.
  • Handle: RePEc:eee:pubeco:v:143:y:2016:i:c:p:73-88 DOI: 10.1016/j.jpubeco.2016.08.011

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    Cited by:

    1. Enikolopov, Ruben & Makarin, Alexey & Petrova, Maria, 2016. "Social Media and Protest Participation: Evidence from Russia," CEPR Discussion Papers 11254, C.E.P.R. Discussion Papers.
    2. Shertzer, Allison, 2016. "Immigrant group size and political mobilization: Evidence from European migration to the United States," Journal of Public Economics, Elsevier, vol. 139(C), pages 1-12.
    3. Fabrizio Germano & Francesco Sobbrio, 2016. "Opinion dynamics via search engines (and other algorithmic gatekeepers)," Economics Working Papers 1552, Department of Economics and Business, Universitat Pompeu Fabra, revised Apr 2017.
    4. Yuriy Gorodnichenko & Tho Pham & Oleksandr Talavera, 2018. "Social media, sentiment and public opinions: Evidence from #Brexit and #USElection," Working Papers 2018-01, Swansea University, School of Management.
    5. Ruben Enikolopov & Maria Petrova & Konstantin Sonin, 2018. "Social Media and Corruption," American Economic Journal: Applied Economics, American Economic Association, vol. 10(1), pages 150-174, January.
    6. Petrova, Maria & Sen, Ananya & Yildirim, Pinar, 2017. "Social Media and Political Donations: New Technology and Incumbency Advantage in the United States," CEPR Discussion Papers 11808, C.E.P.R. Discussion Papers.
    7. Önder, Ali Sina & Portmann, Marco & Stadelmann, David, 2015. "No Place like Home: Opinion Formation with Homophily and Implications for Policy Decisions," Working Paper Series, Center for Fiscal Studies 2015:4, Uppsala University, Department of Economics.
    8. Ascensión Andina-Díaz & José A. García-Martínez & Antonio Parravano, 2017. "The market for scoops: A dynamic approach," Working Papers 2017-03, Universidad de Málaga, Department of Economic Theory, Málaga Economic Theory Research Center.
    9. Levi Boxell & Matthew Gentzkow & Jesse M. Shapiro, 2017. "Is the Internet Causing Political Polarization? Evidence from Demographics," NBER Working Papers 23258, National Bureau of Economic Research, Inc.
    10. repec:eee:socmed:v:187:y:2017:i:c:p:1-10 is not listed on IDEAS

    More about this item


    Political knowledge; Homophily; Social media; Ideological segregation;

    JEL classification:

    • D7 - Microeconomics - - Analysis of Collective Decision-Making
    • D8 - Microeconomics - - Information, Knowledge, and Uncertainty


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