Saved in:
Bibliographic Details
Main Authors: Cheng, Jiahao, Su, Tiancheng, Yuan, Jia, He, Guoxiu, Liu, Jiawei, Tao, Xinqi, Xie, Jingwen, Li, Huaxia
Format: Preprint
Published: 2025
Subjects:
Online Access:https://arxiv.org/abs/2506.17088
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866918141430333440
author Cheng, Jiahao
Su, Tiancheng
Yuan, Jia
He, Guoxiu
Liu, Jiawei
Tao, Xinqi
Xie, Jingwen
Li, Huaxia
author_facet Cheng, Jiahao
Su, Tiancheng
Yuan, Jia
He, Guoxiu
Liu, Jiawei
Tao, Xinqi
Xie, Jingwen
Li, Huaxia
contents Large Language Models (LLMs) often exhibit \textit{hallucinations}, generating factually incorrect or semantically irrelevant content in response to prompts. Chain-of-Thought (CoT) prompting can mitigate hallucinations by encouraging step-by-step reasoning, but its impact on hallucination detection remains underexplored. To bridge this gap, we conduct a systematic empirical evaluation. We begin with a pilot experiment, revealing that CoT reasoning significantly affects the LLM's internal states and token probability distributions. Building on this, we evaluate the impact of various CoT prompting methods on mainstream hallucination detection methods across both instruction-tuned and reasoning-oriented LLMs. Specifically, we examine three key dimensions: changes in hallucination score distributions, variations in detection accuracy, and shifts in detection confidence. Our findings show that while CoT prompting helps reduce hallucination frequency, it also tends to obscure critical signals used for detection, impairing the effectiveness of various detection methods. Our study highlights an overlooked trade-off in the use of reasoning. Code is publicly available at: https://github.com/ECNU-Text-Computing/cot-hallu-detect .
format Preprint
id arxiv_https___arxiv_org_abs_2506_17088
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Chain-of-Thought Prompting Obscures Hallucination Cues in Large Language Models: An Empirical Evaluation
Cheng, Jiahao
Su, Tiancheng
Yuan, Jia
He, Guoxiu
Liu, Jiawei
Tao, Xinqi
Xie, Jingwen
Li, Huaxia
Computation and Language
Large Language Models (LLMs) often exhibit \textit{hallucinations}, generating factually incorrect or semantically irrelevant content in response to prompts. Chain-of-Thought (CoT) prompting can mitigate hallucinations by encouraging step-by-step reasoning, but its impact on hallucination detection remains underexplored. To bridge this gap, we conduct a systematic empirical evaluation. We begin with a pilot experiment, revealing that CoT reasoning significantly affects the LLM's internal states and token probability distributions. Building on this, we evaluate the impact of various CoT prompting methods on mainstream hallucination detection methods across both instruction-tuned and reasoning-oriented LLMs. Specifically, we examine three key dimensions: changes in hallucination score distributions, variations in detection accuracy, and shifts in detection confidence. Our findings show that while CoT prompting helps reduce hallucination frequency, it also tends to obscure critical signals used for detection, impairing the effectiveness of various detection methods. Our study highlights an overlooked trade-off in the use of reasoning. Code is publicly available at: https://github.com/ECNU-Text-Computing/cot-hallu-detect .
title Chain-of-Thought Prompting Obscures Hallucination Cues in Large Language Models: An Empirical Evaluation
topic Computation and Language
url https://arxiv.org/abs/2506.17088