Who says what? Social networks and digital inequalities in online political expression and content creation

Political expression has flourished online, especially on social media platforms, but there are also participation gaps associated with long-standing social and digital inequalities including socio-demographics, political capital, and internet practices. In this study, we examine how network characteristics such as size and diversity contribute to gaps in online political expression and content creation, as well as whether they mediate the stratificational effects of antecedent factors. We test these possibilities using data from a two-wave panel survey of adult internet users in the United States collected just before and after the 2018 U.S. midterm elections. Our findings show relatively wide participation gaps associated with network diversity, which also mediates the influence of political interest and digital news use. We argue that more attention should be paid to network inequalities in online participation, particularly whether they arise from fundamentally unfair social conditions.