Archimedes-AUEB at SemEval-2024 Task 5: LLM explains Civil Procedure

Odysseas Chlapanis, Ion Androutsopoulos, Dimitrios Galanis


Abstract
The SemEval task on Argument Reasoning in Civil Procedure is challenging in that it requires understanding legal concepts and inferring complex arguments. Currently, most Large Language Models (LLM) excelling in the legal realm are principally purposed for classification tasks, hence their reasoning rationale is subject to contention. The approach we advocate involves using a powerful teacher-LLM (ChatGPT) to extend the training dataset with explanations and generate synthetic data. The resulting data are then leveraged to fine-tune a small student-LLM. Contrary to previous work, our explanations are not directly derived from the teacher’s internal knowledge. Instead they are grounded in authentic human analyses, therefore delivering a superior reasoning signal. Additionally, a new ‘mutation’ method generates artificial data instances inspired from existing ones. We are publicly releasing the explanations as an extension to the original dataset, along with the synthetic dataset and the prompts that were used to generate both. Our system ranked 15th in the SemEval competition. It outperforms its own teacher and can produce explanations aligned with the original human analyses, as verified by legal experts.
Anthology ID:
2024.semeval-1.229
Volume:
Proceedings of the 18th International Workshop on Semantic Evaluation (SemEval-2024)
Month:
June
Year:
2024
Address:
Mexico City, Mexico
Editors:
Atul Kr. Ojha, A. Seza Doğruöz, Harish Tayyar Madabushi, Giovanni Da San Martino, Sara Rosenthal, Aiala Rosá
Venue:
SemEval
SIG:
SIGLEX
Publisher:
Association for Computational Linguistics
Note:
Pages:
1607–1622
Language:
URL:
https://aclanthology.org/2024.semeval-1.229
DOI:
10.18653/v1/2024.semeval-1.229
Bibkey:
Cite (ACL):
Odysseas Chlapanis, Ion Androutsopoulos, and Dimitrios Galanis. 2024. Archimedes-AUEB at SemEval-2024 Task 5: LLM explains Civil Procedure. In Proceedings of the 18th International Workshop on Semantic Evaluation (SemEval-2024), pages 1607–1622, Mexico City, Mexico. Association for Computational Linguistics.
Cite (Informal):
Archimedes-AUEB at SemEval-2024 Task 5: LLM explains Civil Procedure (Chlapanis et al., SemEval 2024)
Copy Citation:
PDF:
https://aclanthology.org/2024.semeval-1.229.pdf
Supplementary material:
 2024.semeval-1.229.SupplementaryMaterial.txt
Supplementary material:
 2024.semeval-1.229.SupplementaryMaterial.zip