Unsupervised Real-Time Hallucination Detection based on the Internal States of Large Language Models

Weihang Su, Changyue Wang, Qingyao Ai, Yiran Hu, Zhijing Wu, Yujia Zhou, Yiqun Liu


Abstract
Hallucinations in large language models (LLMs) refer to the phenomenon of LLMs producing responses that are coherent yet factually inaccurate. This issue undermines the effectiveness of LLMs in practical applications, necessitating research into detecting and mitigating hallucinations of LLMs. Previous studies have mainly concentrated on post-processing techniques for hallucination detection, which tend to be computationally intensive and limited in effectiveness due to their separation from the LLM’s inference process. To overcome these limitations, we introduce MIND, an unsupervised training framework that leverages the internal states of LLMs for real-time hallucination detection without requiring manual annotations. Additionally, we present HELM, a new benchmark for evaluating hallucination detection across multiple LLMs, featuring diverse LLM outputs and the internal states of LLMs during their inference process. Our experiments demonstrate that MIND outperforms existing state-of-the-art methods in hallucination detection.
Anthology ID:
2024.findings-acl.854
Volume:
Findings of the Association for Computational Linguistics ACL 2024
Month:
August
Year:
2024
Address:
Bangkok, Thailand and virtual meeting
Editors:
Lun-Wei Ku, Andre Martins, Vivek Srikumar
Venue:
Findings
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
14379–14391
Language:
URL:
https://aclanthology.org/2024.findings-acl.854
DOI:
Bibkey:
Cite (ACL):
Weihang Su, Changyue Wang, Qingyao Ai, Yiran Hu, Zhijing Wu, Yujia Zhou, and Yiqun Liu. 2024. Unsupervised Real-Time Hallucination Detection based on the Internal States of Large Language Models. In Findings of the Association for Computational Linguistics ACL 2024, pages 14379–14391, Bangkok, Thailand and virtual meeting. Association for Computational Linguistics.
Cite (Informal):
Unsupervised Real-Time Hallucination Detection based on the Internal States of Large Language Models (Su et al., Findings 2024)
Copy Citation:
PDF:
https://aclanthology.org/2024.findings-acl.854.pdf