The Great and Widening Divide: Political False Polarization and its Consequences

American politics is becoming increasingly ideologically divided, and this cross-party hostility is reflected in pronounced partisan media outrage. However, while actual ideological polarization has indeed been rising, people estimate an ideological gap as being even larger than reality. We focus on whether part of this cross-party dislike can be explained by illusory perceptions of opposing party attitudes, attitudes the majority of the party members do not actually endorse. This illusory gap is referred to as false polarization; it is an interpersonal bias where a perceiver believes an opponent’s position is much farther away conceptually from where that opponent actually reports their position to be. Over three studies, we explore in which instances false polarization occurs, as well as the downstream consequences of falsely perceiving opposing party attitudes. In Study 1 (N = 1235), we established that liberals and conservatives are likely to over-estimate the prevalence of opposing party attitudes when the partisan issues they are presented with are extreme, rather than mild. Study 2 (N = 816) replicated these patterns, and also revealed that the perception of opponent party agreement with extreme issues correlated with cross-party dislike, and unwillingness to engage (starting political discussions, sharing taxis, etc.). Additionally, the amount of time participants spent watching partisan media (Fox News or MSNBC) positively correlated with the degree of agreement perceived with conservative and liberal issues, respectively. In Study 3 (N = 300), false polarization findings were again replicated, and we found that participants attributed much of their dislike of opposing party members to their perceived (but over-estimated) agreement on extreme issues. As these consequences of false polarization pertain to the desire to interact with opposing party members, they have the potential to undermine the motivation to work towards communication and compromise which are fundamental to the democratic process. Political False Polarization 3 Acknowledgements I would first like to formally thank my funding sources for providing the means to conduct this research. Without contributions from the Canadian Institute for Advanced Research (CIFAR) and the Social Sciences and Humanities Research Council (SSHRC), this project could not have been carried out. I would also like to extend my sincerest gratitude to my supervisor, Dr. Anne E. Wilson, who has been so much more than a mentor to me throughout this process, providing her guidance, expertise, and emotional support every step of the way. I could not have developed this research stream, or my own competencies as a researcher without her encouragement and direction. I would also like to thank Dr. Roger Buehler, and Dr. Justin Cavallo for being a part of my defense committee, and offering their suggestions and recommendations for not only this document, but future research projects as well. They were an integral part of the refinement and completion of this thesis. Finally, I would like to thank my family, friends, and partner, for being an army of support, encouraging me to continue whenever the process became difficult. I would like to thank my father especially; he inspired much of my scientific curiosity and desire to make sense of absurdity. Thank you to all of those mentioned; I am forever appreciative of your contributions. Political False Polarization 4 Table of