The Subgenre Classification of Modern Japanese Novels Using Topic Modeling (LDA) ：An Exploratory Study

This paper explores the application of topic model-based document classification to the study of literary history, focusing on the classification of modern novels into thematic categories that function as “subgenres.” By conducting a topic model analysis on a dataset of full-text digital files of modern novels from the National Diet Library of Japan, I investigate how topics can be interpreted as potential subgenres within the broader literary context.Section 1 reviews traditional perspectives on genre in literary criticism and research, establishing a foundation for identifying and positioning subgenres within the framework of topic modeling. Section 2 builds upon this by defining the criteria and methodologies for determining subgenres through topic models. In Section 3, we conduct a concrete analysis using Latent Dirichlet Allocation (LDA) to examine a selection of full-text files of modern novels from the 1870s to the 1940s, employing a diachronic approach. Section 4 then narrows this diachronic analysis by examining decade-specific trends across the same period. While this study remains in a preliminary phase, Section 5 discusses the potential implications and future directions that topic modeling analysis may offer to literary historical research.