Persuading the Enemy: Estimating the Persuasive Effects of Partisan Media with the Preference-Incorporating Choice and Assignment Design

Does media choice causepolarization, ormerely reflect it? We investigate a critical aspect of this puzzle: How part is an media contribute to attitude polarization among different groups ofmedia consumers. We implement a new experimental design, called the Preference-Incorporating Choice and Assignment(PICA) design, that incorporatesbothfree choice andforcedexposure. We estimate jointly thedegree of polarization caused by selective exposure and the persuasive effect of partisan media. Our design also enables us to conduct sensitivity analyses accounting for discrepancies between stated preferences and actual choice, a potential source of bias ignored in previous studies using similar designs. We find that partisanmedia can polarize both its regular consumers and inadvertent audiences who would otherwise not consume it, but ideologically opposing media potentially also can ameliorate the existing polarization between consumers. Taken together, these results deepen our understanding of when and how media polarize individuals.