Link Prediction and Cascading within Subreddits

Abstract

Reddit is a social news aggregation and discussion website, where members post content like text, posts, images etc. Posts are organized by subject boards called “communities” or “Subreddits”, which cover various topics such as news, politics, science, movies, video games etc. “Subreddits” become a channel of propagation of information when a post at one subreddit is linked or tagged in another subreddit. We formulate this network as a Graph, where each node is a “Subreddit” and edges are existing hyperlinks between them. Given a pair of nodes (“Subreddits”) in that graph, we wish to predict the probability that of one subreddit hyperlinking or tagging a post in the other subreddit.