Neural Topic Models for Hierarchical Topic Detection and Visualization

Given a corpus of documents, hierarchical topic detection aims to learn a topic hierarchy where the topics are more general at high levels of the hierarchy and they become more specific toward the low levels. In this paper, we consider the joint problem of hierarchical topic detection and document visualization. We propose a joint neural topic model that can not only detect topic hierarchies but also generate a visualization of documents and their topic structure. By being able to view the topic hierarchy and see how documents are visually distributed across the hierarchy, we can quickly identify documents and topics of interest with desirable granularity. We conduct both quantitative and qualitative experiments on real-world large datasets. The results show that our method produces a better hierarchical visualization of topics and documents while achieving competitive performance in hierarchical topic detection, as compared to state-of-the-art baselines.