arXiv Computation and Language By Linghao Meng, Feng He, Xuan Yang, Junyuan Mao, Pinze Ren, Deqing Mu, Hesen Yang, Qiankun Li

PHRBench: A Behavioral Evaluation of Post-Hallucination Reasoning in LLMs

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PHRBench is a new benchmark that evaluates how large language models handle hallucinated information during multi-stage reasoning. It tests 18 models across four domains using 4,820 controlled instances, measuring Hallucination Compliance, Hallucination Avoidance, and Heuristic Correction to determine if a model can correct hallucinated premises and still reach the correct answer. The study finds that successful recovery is rare, often requires frequent belief updates, and that features of the hallucinated prompt can predict recovery with an AUROC of 0.847.

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