A Multiscale Geometric Method for Capturing Relational Topic Alignment

TL;DR

This paper introduces a geometric, multiscale method combining text and network data to improve the detection of rare topics and visualize their evolution over time in scientific research communities.

Contribution

It presents a novel hierarchical approach using Hellinger distances and Ward's linkage to align topics across time, capturing both local and global structures.

Findings

Effectively identifies rare and niche topics.

Visualizes smooth temporal topic drift.

Enhances interpretability of topic models.

Abstract

Interpretable topic modeling is essential for tracking how research interests evolve within co-author communities. In scientific corpora, where novelty is prized, identifying underrepresented niche topics is particularly important. However, contemporary models built from dense transformer embeddings tend to miss rare topics and therefore also fail to capture smooth temporal alignment. We propose a geometric method that integrates multimodal text and co-author network data, using Hellinger distances and Ward's linkage to construct a hierarchical topic dendrogram. This approach captures both local and global structure, supporting multiscale learning across semantic and temporal dimensions. Our method effectively identifies rare-topic structure and visualizes smooth topic drift over time. Experiments highlight the strength of interpretable bag-of-words models when paired with principled geometric alignment.