Pengwei Yan
Author directory2026
EpiPersona: Persona Projection and Episode Coupling for Pluralistic Preference Modeling
Yujie Zhang | Weikang Yuan | Zhuoren Jiang | Pengwei Yan
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
Yujie Zhang | Weikang Yuan | Zhuoren Jiang | Pengwei Yan
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
Pluralistic alignment is essential for adapting large language models (LLMs) to the diverse preferences of individuals and minority groups. However, existing personalized reward models often mix stable personal traits with episode-specific factors, limiting their ability to generalize across episodes. To address this challenge, we propose EpiPersona, a framework for explicit persona–episode coupling. EpiPersona first projects noisy preference feedback into a low-dimensional persona space, where similar personas are aggregated into shared discrete codewords. This process separates enduring personal characteristics from situational signals without relying on predefined preference dimensions. The inferred persona representation is then coupled with the current episode, enabling episode-aware preference prediction. Extensive experiments show that EpiPersona outperforms the baselines. It achieves notable performance gains in hard episodic-shift scenarios, while remaining effective with sparse preference data.
2024
Can Large Language Models Grasp Legal Theories? Enhance Legal Reasoning with Insights from Multi-Agent Collaboration
Weikang Yuan | Junjie Cao | Zhuoren Jiang | Yangyang Kang | Jun Lin | Kaisong Song | Tianqianjin Lin | Pengwei Yan | Changlong Sun | Xiaozhong Liu
Findings of the Association for Computational Linguistics: EMNLP 2024
Weikang Yuan | Junjie Cao | Zhuoren Jiang | Yangyang Kang | Jun Lin | Kaisong Song | Tianqianjin Lin | Pengwei Yan | Changlong Sun | Xiaozhong Liu
Findings of the Association for Computational Linguistics: EMNLP 2024
Large Language Models (LLMs) could struggle to fully understand legal theories and perform complex legal reasoning tasks. In this study, we introduce a challenging task (confusing charge prediction) to better evaluate LLMs’ understanding of legal theories and reasoning capabilities. We also propose a novel framework: Multi-Agent framework for improving complex Legal Reasoning capability (MALR). MALR employs non-parametric learning, encouraging LLMs to automatically decompose complex legal tasks and mimic human learning process to extract insights from legal rules, helping LLMs better understand legal theories and enhance their legal reasoning abilities. Extensive experiments on multiple real-world datasets demonstrate that the proposed framework effectively addresses complex reasoning issues in practical scenarios, paving the way for more reliable applications in the legal domain.