Legal Information as a Complex Network: Improving Topic Modeling Through Homophily

  • Kazuki AshiharaEmail author
  • Chenhui Chu
  • Benjamin Renoust
  • Noriko Okubo
  • Noriko Takemura
  • Yuta Nakashima
  • Hajime Nagahara
Conference paper
Part of the Studies in Computational Intelligence book series (SCI, volume 882)


Topic modeling is a key component to computational legal science. Network analysis is also very important to further understand the structure of references in legal documents. In this paper, we improve topic modeling for legal case documents by using homophily networks derived from two families of references: prior cases and statute laws. We perform a detailed analysis on a rich legal case dataset in order to create these networks. The use of the reference-induced homophily topic modeling improves on prior methods.


Network of legal documents Topic modeling Homophily 


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Copyright information

© Springer Nature Switzerland AG 2020

Authors and Affiliations

  • Kazuki Ashihara
    • 1
    Email author
  • Chenhui Chu
    • 1
  • Benjamin Renoust
    • 1
  • Noriko Okubo
    • 1
  • Noriko Takemura
    • 1
  • Yuta Nakashima
    • 1
  • Hajime Nagahara
    • 1
  1. 1.Graduate of Information Science and Technology, Institute for Datability Science, Graduate School of Law and PoliticsOsaka UniversityOsakaJapan

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