## 4 Data, Analysis, and Observations
### Analysis of Interconnectedness of Subreddits  
Next, we analyzed the \"interconnectedness\" of the subreddits. We first computed the \"interconnectedness score\" of each subreddit based on the definition given in Section 3. Before computing the \"interconnectedness\" score, we removed subreddits that were not popular, which is the case when they do not have many users. We controlled this with a parameter \(\gamma\). Thus, we only considered subreddits that had more than \(\gamma\) users. For our experiments, we set \(\gamma=100\) as it is realistic to expect an active subreddit to have more than a hundred users. Next, for all the subreddits that had \(\gamma\) or more users, we filtered users who were not active in the subreddit. Thus, for each of the subreddits with \(\gamma\) or more users, we considered only those users in a subreddit who had posted or commented more than \(\beta\) times in the subreddit. We only used information from these users for computing the interconnectedness score. Note that this is natural as we would want to only concentrate on users who are actively participating in conversations in the active subreddits. Finally, we computed the interconnectedness score for each of these subreddits and created a weighted interconnectedness graph which we called the \"Reddit Interconnectedness Graph (RIG)\". In the RIG, the nodes are the subreddits and there is a directed edge between the nodes (subreddits) \(S_{i}\) and \(S_{j}\) if the former is interconnected to the latter. The weight of this edge is set to be equal to the interconnectedness score between \(S_{i}\) and \(S_{j}\). Finally, we pruned the RIG using weight pruning as defined earlier for the SIGs (see Section 3) using the parameter \(a\). Since the interconnectedness score is a number between 0 and 1, we only kept edges in the RIG that had a weight greater than 0.1. The resultant RIG is shown in Figure 14. We note that there is a large connected component (shown in the blue circle) in this graph. Looking deeper into this component, we found that all the subreddits in this group are NSFW. Furthermore, they are all interconnected among each other but are sparsely connected with other subreddits. Figure 15 shows an expanded view of the part of Figure 14, which is circled in _black_ and shows the large circle of highly interconnected NSFW subreddits. It can be clearly seen from this figure that though the NSFW subreddits are connected with each other, they are not connected with other regular subreddits. It must also be noted that two other groups of highly interconnected subreddits are shown in Figure 14 which are also circled in _black_. One of these has five subreddits and the other has seven (see Figure 16 where they are shown separately). Again, looking deeper into these components, it is clear that these are NSFW subreddits as well and have similar interconnection patterns with non-NSFW subreddits. We also noted that some subreddits in these groups are connected with subreddits in the bigger NSFW group. For our final analysis, we sorted all the subreddits by the interconnectedness score and selected the top \(k\) for further analysis. For our experiments, we selected \(k=100\). The results of this analysis are shown in Figure 17. We found that out of the top 100 highly interconnected subreddits, 96 were NSFW (dealing with pornography, shown in blue), two were banned (green), and two were regular subreddits (orange). When we analyzed the implicit leader-follower structure of the NSFW subreddits, which are identified by their interconnectedness score, we found that the discussions in these groups were driven by the implicit leaders while the consumers of the information were the implicit followers.