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Less is Better: Constructing Legal Question Answering System by Weighing Longest Common Subsequence of Disjunctive Union Text

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New Frontiers in Artificial Intelligence (JSAI-isAI 2022)

Abstract

This article is prepared for submission to Competition on Legal Information Extraction/Entailment (COLIEE 2022), an international competitive event organized to focus on information processing and retrieval. The proposed method tackles on how to construct an answering system capable of responding Yes/No legal questions, ultimately recognizing entailment between legal queries from past Japanese bar exams and relevant articles of Japan Civil Code (both in Japanese). We first attempted to extract disjunctive union text from each training query and relevant article(s) with corresponding ‘Y/N’ answers as their labels, eventually forming our reference database (training set). Then the same process was repeated on a sample of different queries and relevant articles yet without a ‘Y/N’ label as the input (testing set). Finally, when constructing our model, the similarity ratio between the test disjunctive union and the training disjunctive union by longest common subsequence was calculated as its basis. As a result, this model achieved an accuracy of 0.6055 in Task 4 (rank 3rd as a team, and 7th as a trial). This is an extremely simple and efficient model capable of satisfactory performance.

M. Lin, S.-C. Huang and H.-L. Shao—All authors contributed equally to this work.

H.-L. Shao—Corresponding author

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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. Rabelo, J., Kim, M.Y., Goebel, R., Yoshioka, M., Kano, Y., Satoh, K.: COLIEE 2020: methods for legal document retrieval and entailment (2020). https://sites.ualberta.ca/~rabelo/COLIEE2021/COLIEE_2020_summary.pdf

  3. Rabelo, J., Goebel, R., Kim, M.Y., Kano, Y., Yoshioka, M., Satoh, K.: Overview and discussion of the competition on legal information extraction/entailment (COLIEE) 2021. Rev. Socionetwork Strat. 16, 111–133 (2022). https://doi.org/10.1007/s12626-022-00105-z

    Article  Google Scholar 

  4. COLIEE organizer. COLIEE-2022 main webpage, Online (2022). https://sites.ualberta.ca/~rabelo/COLIEE2022/

  5. Tohoku NLP Group. Pretrained Japanese BERT models (BERT-base_mecab-ipadic-char-4k_whole-word-mask) (2022). https://github.com/cl-tohoku/bert-japanese

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

  7. Kasper, R.T.: A logical semantics for feature structures. In: 24th Annual Meeting of the Association for Computational Linguistics, pp. 257–266 (1986)

    Google Scholar 

  8. Eiter, T., Gottlob, G., Mannila, H.: Disjunctive datalog. ACM Trans. Database Syst. (TODS) 22(3), 364–418 (1997)

    Article  Google Scholar 

  9. Eiter, T., Gottlob, G.: On the computational cost of disjunctive logic programming: propositional case. Ann. Math. Artif. Intell. 15(3), 289–323 (1995)

    Article  MathSciNet  MATH  Google Scholar 

  10. Tran, V., Le Nguyen, M., Tojo, S., Satoh, K.: Encoded summarization: summarizing documents into continuous vector space for legal case retrieval. Artif. Intell. Law 28(4), 441–467 (2020). https://doi.org/10.1007/s10506-020-09262-4

    Article  Google Scholar 

  11. Tran, V., Nguyen, M., Satoh, K.: Building legal case retrieval systems with lexical matching and summarization using a pre-trained phrase scoring model. In: ICAIL 2019: Proceedings of the Seventeenth International Conference on Artificial Intelligence and Law June 2019 (2020). https://doi.org/10.1145/3322640.3326740

  12. Anan, Y., Hatano, K., Bannai, H., Takeda, M., Satoh, K.: Polyphonic music classification on symbolic data using dissimilarity functions. In: ISMIR, pp. 229–234 (2012)

    Google Scholar 

  13. Deken, J.G.: Some limit results for longest common subsequences. Discret. Math. 26(1), 17–31 (1979)

    Article  MathSciNet  MATH  Google Scholar 

  14. Shao, H.-L., Chen, Y.-C., Huang, S.-C.: BERT-based ensemble model for statute law retrieval and legal information entailment. In: Okazaki, N., Yada, K., Satoh, K., Mineshima, K. (eds.) JSAI-isAI 2020. LNCS (LNAI), vol. 12758, pp. 226–239. Springer, Cham (2021). https://doi.org/10.1007/978-3-030-79942-7_15

    Chapter  Google Scholar 

  15. Bergroth, L., Hakonen, H., Raita, T.: A survey of longest common subsequence algorithms. In: Proceedings Seventh International Symposium on String Processing and Information Retrieval. SPIRE 2000, pp. 39–48. IEEE (2000)

    Google Scholar 

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Acknowledgment

Hsuan-lei Shao, “Knowledge Graph of China Studies: Knowledge Extraction, Graph Database, Knowledge Generation” (110-2628-H-003-002-MY4, Ministry of Science and Technology, the MOST), Taiwan.

Sieh-chuen Huang, “A Study on Property Management Regimes in Family and Succession Law in Taiwan” (110-2410-H-002-026-MY3, Ministry of Science and Technology, the MOST), Taiwan.

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Lin, M., Huang, Sc., Shao, Hl. (2023). Less is Better: Constructing Legal Question Answering System by Weighing Longest Common Subsequence of Disjunctive Union Text. In: Takama, Y., Yada, K., Satoh, K., Arai, S. (eds) New Frontiers in Artificial Intelligence. JSAI-isAI 2022. Lecture Notes in Computer Science(), vol 13859. Springer, Cham. https://doi.org/10.1007/978-3-031-29168-5_11

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  • DOI: https://doi.org/10.1007/978-3-031-29168-5_11

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