Deconstructing the structure of online conversations on Reddit

The Internet has made it easier for social scientists to study human behavior by analyzing their interactions on social media platforms. Many of these platforms characterize conversations among users via threads, which induce a tree-like structure. The structural properties of these discussion trees, such as their width, depth, and size, can be used to make inferences regarding user discussion patterns and conversation dynamics. In this paper, we seek to understand the structure of these online discussions on Reddit. We characterize the structure of these discussions via a set of global and local discussion-tree properties. The global features constitute information regarding the community/subreddit of a given post, whereas the local features are comprised of the properties of the post itself. We perform various statistical analyses on a year's worth of Reddit data containing a quarter of a million posts and several million comments. These analyses allow us to tease apart the relative contribution of a discussion post's global and local properties and characterize the importance of specific individual features in determining the discussions' structural patterns. Our results indicate that both local and global features explain a significant amount of structural variation. Local features are collectively more important as they explain significantly more variation in the discussion trees' structural properties than global features. However, there is significant heterogeneity in the impact of the various features. Several global features, e.g., the topic, age, popularity, and the redundancy of content in a subreddit, also play a crucial role in understanding the specific properties of discussion trees.