TimeChara: Evaluating Point-in-Time Character Hallucination of Role-Playing Large Language Models

Jaewoo Ahn, Taehyun Lee, Junyoung Lim, Jin-Hwa Kim, Sangdoo Yun, Hwaran Lee, Gunhee Kim


Abstract
While Large Language Models (LLMs) can serve as agents to simulate human behaviors (i.e., role-playing agents), we emphasize the importance of point-in-time role-playing. This situates characters at specific moments in the narrative progression for three main reasons: (i) enhancing users’ narrative immersion, (ii) avoiding spoilers, and (iii) fostering engagement in fandom role-playing. To accurately represent characters at specific time points, agents must avoid character hallucination, where they display knowledge that contradicts their characters’ identities and historical timelines. We introduce TimeChara, a new benchmark designed to evaluate point-in-time character hallucination in role-playing LLMs. Comprising 10,895 instances generated through an automated pipeline, this benchmark reveals significant hallucination issues in current state-of-the-art LLMs (e.g., GPT-4o). To counter this challenge, we propose Narrative-Experts, a method that decomposes the reasoning steps and utilizes narrative experts to reduce point-in-time character hallucinations effectively. Still, our findings with TimeChara highlight the ongoing challenges of point-in-time character hallucination, calling for further study.
Anthology ID:
2024.findings-acl.197
Volume:
Findings of the Association for Computational Linguistics: ACL 2024
Month:
August
Year:
2024
Address:
Bangkok, Thailand
Editors:
Lun-Wei Ku, Andre Martins, Vivek Srikumar
Venue:
Findings
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
3291–3325
Language:
URL:
https://aclanthology.org/2024.findings-acl.197
DOI:
10.18653/v1/2024.findings-acl.197
Bibkey:
Cite (ACL):
Jaewoo Ahn, Taehyun Lee, Junyoung Lim, Jin-Hwa Kim, Sangdoo Yun, Hwaran Lee, and Gunhee Kim. 2024. TimeChara: Evaluating Point-in-Time Character Hallucination of Role-Playing Large Language Models. In Findings of the Association for Computational Linguistics: ACL 2024, pages 3291–3325, Bangkok, Thailand. Association for Computational Linguistics.
Cite (Informal):
TimeChara: Evaluating Point-in-Time Character Hallucination of Role-Playing Large Language Models (Ahn et al., Findings 2024)
Copy Citation:
PDF:
https://aclanthology.org/2024.findings-acl.197.pdf