We concluded data collection for an online discussion field experiment on Reddit.

Over 500 participants, regular users of the online platform Reddit, discussed political issues in six different online communities (subreddits) that were experimentally controlled by the researchers. The discussions spanned a four-week period and participants generated more than 5,000 comments in response to political statements regarding 20 different political issues (including climate change, the war in Ukraine, health care, etc.) that were seeded by the researchers.

In addition to the discussion data (see Figure 1), we collected extensive survey information from participants in a pre-discussion survey, a post-discussion survey and brief check-in surveys at the end of every discussion week. The pre and post surveys included detailed questions on demographics, online activity and political variables, whereas the check-in surveys asked participants about their motives for commenting as well as their perceptions of the group, the discussion climate, and other group members’ attitudes regarding the discussed political issues.

Finally, this study contained two experimental treatments that participants were randomly assigned to at the beginning of the study. Besides a control group that did not receive any treatment, one treatment group was incentivized in the form of gift vouchers to participate consistently to activate otherwise silent users that read along on social media but rarely write comments themselves. A second treatment group was informed about community rules to be “civil, respectful, and on-topic while discussing the political issues of the day” while also Reddit’s internal technical moderation settings were activated to reduce the impact of highly active but uncivil users who may otherwise skew online discourse.

This combination of fine-grained survey data along long-term discussion data, involving large groups of up to 100 participants on an existing social media platform, is a unique opportunity to examine dynamics of online discourse under conditions of experimental control but high ecological validity.