arXiv Computation and Language By Wei Huang, Keping Bi, Yinqiong Cai, Wei Chen, Jiafeng Guo, Xueqi Cheng

How Do LLM-Generated Texts Impact Term-Based Retrieval Models?

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The paper examines how large language model (LLM)-generated texts affect term-based retrieval models such as BM25. It finds that LLM outputs have smoother high-frequency and steeper low-frequency Zipf slopes, higher term specificity, and greater document-level diversity, traits that align with LLMs’ focus on reader experience. The study shows that term-based models prioritize documents whose term distributions match the queries, rather than showing an inherent bias toward the source of the text.

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