Recent studies demonstrate that query expansions generated by large language models (LLMs) can considerably enhance information retrieval systems by generating hypothetical documents that answer the queries as expansions. However, challenges arise from misalignments between the expansions and the retrieval corpus, resulting in issues like hallucinations and outdated information due to the limited intrinsic knowledge of LLMs. Inspired by Pseudo Relevance Feedback (PRF), we introduce Corpus-Steered Query Expansion (CSQE) to promote the incorporation of knowledge embedded within the corpus. CSQE utilizes the relevance assessing capability of LLMs to systematically identify pivotal sentences in the initially-retrieved documents. These corpus-originated texts are subsequently used to expand the query together with LLM-knowledge empowered expansions, improving the relevance prediction between the query and the target documents. Extensive experiments reveal that CSQE exhibits strong performance without necessitating any training, especially with queries for which LLMs lack knowledge.

运用大语言模型生成的查询扩展可以显著增强信息检索系统，但由于模型的知识有限，导致扩展与检索语料库之间存在错位、产生幻觉和过时信息等问题。为了解决这些挑战，本文提出了基于语料库导向的查询扩展方法，利用大语言模型的相关性评估能力系统地识别初始检索文档中的关键句子，并将这些基于语料库的文本与大语言模型扩展的结果一起用于查询扩展，从而提高查询和目标文档之间的相关性预测。通过广泛的实验证明，该方法在没有任何训练的情况下表现出强大的性能，尤其适用于大语言模型缺乏知识的查询。

使用大型语言模型进行语料导向的查询扩展