Papers › KnowHalu: Hallucination Detection via Multi-Form Knowledge Based Factual Checking

KnowHalu: Hallucination Detection via Multi-Form Knowledge Based Factual Checking

3 Apr 2024arXiv:2404.02935archive 2025-07-28

Jiawei Zhang, Chejian Xu, Yu Gai, Freddy Lecue, Dawn Song, Bo Li

This paper introduces KnowHalu, a novel approach for detecting hallucinations in text generated by large language models (LLMs), utilizing step-wise reasoning, multi-formulation query, multi-form knowledge for factual checking, and fusion-based detection mechanism. As LLMs are increasingly applied across various domains, ensuring that their outputs are not hallucinated is critical. Recognizing the limitations of existing approaches that either rely on the self-consistency check of LLMs or perform post-hoc fact-checking without considering the complexity of queries or the form of knowledge, KnowHalu proposes a two-phase process for hallucination detection. In the first phase, it identifies non-fabrication hallucinations--responses that, while factually correct, are irrelevant or non-specific to the query. The second phase, multi-form based factual checking, contains five key steps: reasoning and query decomposition, knowledge retrieval, knowledge optimization, judgment generation, and judgment aggregation. Our extensive evaluations demonstrate that KnowHalu significantly outperforms SOTA baselines in detecting hallucinations across diverse tasks, e.g., improving by 15.65% in QA tasks and 5.50% in summarization tasks, highlighting its effectiveness and versatility in detecting hallucinations in LLM-generated content.

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clean_query javyduck/knowhalu/utils.py official repository ran fingerprinted no licence file found · pointer only · 31ec3bc0276666f0 · report
extract_query javyduck/knowhalu/utils.py official repository ran fingerprinted no licence file found · pointer only · b85a0fb8ce05a717 · report
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wiki_retrieval javyduck/knowhalu/retrieve.py official repository unverified no licence file found · pointer only · 9df0d4d165fb9248 · report

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Fact CheckingFormHallucinationRetrieval

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