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Open Access Thesis

Document Type


Degree Program


Degree Type

Master of Arts (M.A.)

Year Degree Awarded


Month Degree Awarded



Over the last several decades there has been a debate among social scientists on whether the United States has become, or is in the process of being, politically polarized. These conversations started with discussion of the “culture wars,” moved to the discussion of selective exposure and media outrage, and currently involve concerns about online radicalization and the spread of online misinformation. Throughout these themes one characteristic has remained constant: a lack of systematic evidence despite anecdotes and feelings of animosity between the two parties. Today researchers are beginning to shift from operationalizing political polarization as growing divides in attitudes towards policy issues towards a focus on political animosity. Scholars attempting to understand the origins of affective polarization have looked at the effect of political identity, out-group perceptions, and the diffusion of moral and emotional content in social media networks. In the current study I build on this literature using a panel of longitudinal data Twitter users to examine whether there is an association between following prominent partisan Twitter accounts and the expression of emotional valence through Tweeting or Retweeting. I take a relational approach to analysis by examining how this relationship varies between networks of Twitter users and under different historical circumstances. I argue that this relational approach is necessary for understanding how political polarization is unfolding in the country and that the lack of a relational approach may explain why political polarization has been downplayed in systematic studies. This study finds that the amount of political polarization on Twitter is dependent both on cultural and historical context. It makes contributions to the literature on political polarization in the United States, research methodology, and has implications for reducing radicalization in online spaces.


First Advisor

Mark Pachucki

Second Advisor

Anthony Paik

Third Advisor

Jonathan Wynn