The influence of group membership on online expressions and polarization on a discussion platform: An experimental study

Despite much attention for group polarization in online environments, little is known about how group membership affects online behavior. We designed an online platform where ethnic minority and majority users in the Netherlands participated in discussions about controversial topics (homosexuality and abortion). Participants were randomly assigned to either progressive, conservative, or mixed discussions on these topics, which were ostensibly held among ethnic minority or majority users. We find that when ethnic minority users are exposed to discussions among the ethnic majority (i.e., outgroup) with which they disagree, they are less likely to express their opinions and more likely to deviate from their personal opinions. Among ethnic majority users, we find the opposite: when confronted with a discussion among the ethnic minority with which they disagree, they are more likely to voice their opinion and less likely to deviate from their personal opinions. This shows that group membership can affect online polarization.