Identifying NSFW Groups on Reddit Social Network by Identifying Highly Interconnected Subreddits Through Analysis of Implicit Communication Patterns

In this paper, we analyze the Reddit social network with the goal of identifying “highly interconnected” subreddits. Intuitively, a subreddit is highly interconnected if the users in the subreddit interact a lot with users from other subreddits in the Reddit ecosystem. To identify the highly interconnected subreddits, we used the communication patterns of the users on the Reddit platform. We definde an “interconnectedness score” that was obtained from user interactions across subreddits. This score was used to identify the highly interconnected subreddits. We also leveraged the interactions among users within the subreddits to identify implicit leader–follower relationships within them. Intuitively, an implicit leader in a subreddit is someone who receives a lot of attention from other users, who are the followers. We inferred the implicit leaders using only the responses they received on their posts from other users in the subreddit. Finally, we studied the role played by these implicit leaders within the interconnected subreddits using the idea of a “leaderness score”. For the analysis, we used data obtained from Reddit in 2022 with a custom-built crawler. We analyzed a total of 125,000 subreddits for this work and identified the group of highly interconnected subreddits using the idea of the interconnectedness score. We manually evaluated the content of the posts on the identified interconnected subreddits in order to understand the nature of these subreddits. Our analysis showed that the highly interconnected subreddits discuss content considered to be “not safe/suitable for work” (NSFW). We also observed that though these subreddits were highly interconnected among themselves, they were sparsely connected with other non-NSFW subreddits. Furthermore, we found that the implicit leaders in these subreddits drove majority of the conversations in these groups. These results are socially significant as they can be used to make online social networks safe for the underage population. Thus, our results can be used for enforcing age-based restrictions on access to these NSFW subreddits. Finally, our results also open up the possibility of moderating the content on these subreddits by enforcing content moderation rules on the implicit leaders who drive the conversation in these groups. Finally, though these results are specific to Reddit, the insights obtained from this analysis can be used for analyzing other large-scale online social networks with similar goals to this study.