Modeling stack overflow tags and topics as a hierarchy of concepts

Abstract

Developers rely on online Q&A forums to look up technical solutions, to pose questions on implementation problems, and to enhance their community profile by contributing answers. Many popular developer communication platforms, such as the Stack Overflow Q&A forum, require threads of discussion to be tagged by their contributors for easier lookup in both asking and answering questions. In this paper, we propose to leverage Stack Overflow’s tags to create a hierarchical organization of concepts discussed on this platform. The resulting concept hierarchy couples tags with a model of their relevancy to prospective questions and answers. For this purpose, we configure and apply a supervised multi-label hierarchical topic model to Stack Overflow questions and demonstrate the quality of the model in several ways: by identifying tag synonyms, by tagging previously unseen Stack Overflow posts, and by exploring how the hierarchy could aid exploratory searches of the corpus. The results suggest that when traversing the inferred hierarchical concept model of Stack Overflow the questions become more specific as one explores down the hierarchy and more diverse as one jumps to different branches. The results also indicate that the model is an improvement over the baseline for the detection of tag synonyms and that the model could enhance existing ensemble methods for suggesting tags for new questions. The paper indicates that the concept hierarchy as a modeling imperative can create a useful representation of the Stack Overflow corpus. This hierarchy can be in turn integrated into development tools which rely on information retrieval and natural language processing, and thereby help developers more efficiently navigate crowd-sourced online documentation.