Educators, Solicitors, Flamers, Motivators, Sympathizers: Characterizing Roles in Online Extremist Movements

Social media provides the means by which extremist social movements, such as white supremacy and anti-LGBTQ, thrive online. Yet, we know little about roles played participants of movements. In this paper, investigate these to characterize their roles, role dynamics, influence in spreading online extremism. Our participants-online accounts-are 4,876 public Facebook pages or groups that have shared information from websites 289 Southern Poverty LawCenter (SPLC) designated groups. Guided theories participatory activism, map sharing features extremists accounts. By clustering quantitative followed qualitative expert validation, identify five surrounding activism-educators, solicitors, flamers, motivators, sympathizers. For example, solicitors use links attract donations participation issues, whereas flamers share inflammatory content inciting anger. We further dynamics as, how stable are over time likely will accounts transition one into another. find core movement-educators solicitors-are more stable, while motivators can sympathizers with high probability. Finally, using a Hawkes process model, test influential various types information. educators exert most triggering link posts, spread fake news sources. results help situating on trajectory deeper engagement movements understanding potential effect counter-extremism interventions. findings implications for flourish through activism they gain spectrum allies mobilizing extremism