What's the Norm Around Here? Individuals' Responses Can Mitigate the Effects of Misinformation Prevalence in Shaping Perceptions of a Community

Social norms play a significant role in how conspiratorial content and related misinformation impact online communities. However, less is understood about the mechanisms by which particular aspects of a community may drive perceptions of social norms in the community. Using anti-vaccine conspiracies as a testbed, this paper experimentally examines three such features and their relationships : prevalence of conspiratorial content, community response, and explicit community rules. Results show that prevalence of content has a significant effect on norm perceptions, while the results did not support the effects of explicit rule on norm perceptions. However, these effects can be mitigated by the way a community responds to such content. Furthermore, perceived norms also influence other expectations about the community, from escalated behaviors to belief in other conspiracy theories. The paper concludes by highlighting the implications of these findings for online platform design, for community governance, and for future research about the relationships among conspiratorial content and norm perceptions.