Edwards, Arthur. "(How) do participants in online discussion forums create ‘echo chambers’?: The inclusion and exclusion of dissenting voices in an online forum about climate change." Journal of Argumentation in Context 2.1 (2013): 127-150.

This paper investigates the dynamics of in-group homogeneity and group polarization in political online forums, specifically analyzing discussions on Climategate.nl, a skeptical Dutch climate change forum. By examining five discussion lines over time, the research reveals how participants respond to dissenting voices, leading to processes of inclusion and exclusion. While the forum gradually developed into an 'echo chamber,' it maintained some diversity. The findings emphasize the editors' role in moderating discussions and suggest that a counter-steering moderation policy is essential to limit group polarization.