Skip to main content

BERT-Based Ensemble Model for Statute Law Retrieval and Legal Information Entailment

  • Conference paper
  • First Online:
New Frontiers in Artificial Intelligence (JSAI-isAI 2020)

Abstract

The Competition on legal information extraction/entailment (COLIEE) is an international information processing and retrieval competition. As an aid to future participants as well as question designers, this article describes how to connect legal questions taken from past Japanese bar exams to relevant statutes (articles of the Japanese Civil Code, Task 3) and how to construct a Yes/No question answering system for legal queries (Task 4) incorporating background materials on Japanese law. We restructured the given data to a dataset which contains all possible combinations of queries and articles as continuous strings as our samples. In this way, the difficult pairing task has been turned into a simpler classification task and samples for training became sufficient in number. Next, we used three BERT-based models to solve binary questions in order to achieve stable performance. As a result, the model achieved an F2-score of 0.6587 in Task 3 (ranked 1st) and an accuracy of 0.6161 in Task 4.

All authors contributed equally to this work.

This is a preview of subscription content, log in via an institution to check access.

Access this chapter

Chapter
USD 29.95
Price excludes VAT (USA)
  • Available as PDF
  • Read on any device
  • Instant download
  • Own it forever
eBook
USD 39.99
Price excludes VAT (USA)
  • Available as EPUB and PDF
  • Read on any device
  • Instant download
  • Own it forever
Softcover Book
USD 54.99
Price excludes VAT (USA)
  • Compact, lightweight edition
  • Dispatched in 3 to 5 business days
  • Free shipping worldwide - see info

Tax calculation will be finalised at checkout

Purchases are for personal use only

Institutional subscriptions

References

  1. Rabelo, J., Kim, M.-Y., Goebel, R., Yoshioka, M., Kano, Y., Satoh, K.: A summary of the COLIEE 2019 competition. In: Sakamoto, M., Okazaki, N., Mineshima, K., Satoh, K. (eds.) JSAI-isAI 2019. LNCS (LNAI), vol. 12331, pp. 34–49. Springer, Cham (2020). https://doi.org/10.1007/978-3-030-58790-1_3

    Chapter  Google Scholar 

  2. Yoshioka, M., Kano, Y., Kiyota, N., Satoh, K.: Overview of Japanese statute law retrieval and entailment task at COLIEE-2018. In: The Proceedings of the 12th International Workshop on Juris-Informatics (JURISIN 2018), pp. 117–128. The Japanese Society of Artificial Intelligence (2018)

    Google Scholar 

  3. Kano, Y., et al.: COLIEE-2018: evaluation of the competition on legal information extraction and entailment. In: Kojima, K., Sakamoto, M., Mineshima, K., Satoh, K. (eds.) JSAI-isAI 2018. LNCS (LNAI), vol. 11717, pp. 177–192. Springer, Cham (2019). https://doi.org/10.1007/978-3-030-31605-1_14

    Chapter  Google Scholar 

  4. COLIEE organizer. COLIEE-2020. https://sites.ualberta.ca/~rabelo/COLIEE2020/

  5. Cl-tohoku, BERT-base_mecab-ipadic-char-4k_whole-word-mask. https://github.com/cl-tohoku/bert-japanese

  6. Alinear-corp, albert-japanese. https://github.com/alinear-corp/albert-japanese

  7. Kingma, D.P., Ba, J.: Adam: a method for stochastic optimization. arXiv preprint arXiv:1412.6980 (2014)

  8. Devlin, J., Chang, M.W., Lee, K., Toutanova, K.: BERT: pre-training of deep bidirectional transformers for language understanding. arXiv preprint arXiv:1810.04805 (2018)

  9. Clark, C., Lee, K., Chang, M.W., Kwiatkowski, T., Collins, M., Toutanova, K.: BoolQ: exploring the surprising difficulty of natural yes/no questions. arXiv preprint arXiv:1905.10044 (2019)

  10. Barskar, R., Ahmed, G., Barskar, N.: An approach for extracting exact answers to question answering (QA) system for English sentences. Procedia Eng. 30, 1187–1194 (2012). https://doi.org/10.1016/j.proeng.2012.01.979

    Article  Google Scholar 

  11. Li, X., et al.: Entity-relation extraction as multi-turn question answering. arXiv preprint arXiv:1905.05529 (2019)

  12. Rabelo, J., Kim, M.Y., Goebel, R., Yoshioka, M., Kano, Y., Satoh, K.: COLIEE 2020: methods for legal document retrieval and entailment. In: Proceedings of the International Workshop on Juris-Informatics 2020 (JURISIN 2020), pp. 114–127 (2020)

    Google Scholar 

Download references

Acknowledgments

This work was financially supported by: Hsuan-Lei Shao, “From Knowledge Genealogy to Knowledge Map-China Studies in Big Data and Machine Learning” (MOST 107-2410-H-003 -058 -MY3), Sieh-Chuen Huang, Center for Research in Econometric Theory and Applications (Grant no. NTU-110L900203) from The Featured Areas Research Center Program within the framework of the Higher Education Sprout Project by the Ministry of Education (MOE) and Ministry of Science and Technology (MOST 109-2634-F-002-045) in Taiwan.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Sieh-Chuen Huang .

Editor information

Editors and Affiliations

Rights and permissions

Reprints and permissions

Copyright information

© 2021 Springer Nature Switzerland AG

About this paper

Check for updates. Verify currency and authenticity via CrossMark

Cite this paper

Shao, HL., Chen, YC., Huang, SC. (2021). BERT-Based Ensemble Model for Statute Law Retrieval and Legal Information Entailment. In: Okazaki, N., Yada, K., Satoh, K., Mineshima, K. (eds) New Frontiers in Artificial Intelligence. JSAI-isAI 2020. Lecture Notes in Computer Science(), vol 12758. Springer, Cham. https://doi.org/10.1007/978-3-030-79942-7_15

Download citation

  • DOI: https://doi.org/10.1007/978-3-030-79942-7_15

  • Published:

  • Publisher Name: Springer, Cham

  • Print ISBN: 978-3-030-79941-0

  • Online ISBN: 978-3-030-79942-7

  • eBook Packages: Computer ScienceComputer Science (R0)

Publish with us

Policies and ethics