arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2402.12352cs.CLcs.IR
收藏

基于图的检索器捕获生物医学知识的长尾

Graph-Based Retriever Captures the Long Tail of Biomedical Knowledge

Boston Consulting Group, AI Institute(波士顿咨询公司AI研究院)

Julien Delile, Srayanta Mukherjee, Anton Van Pamel, Leonid Zhukov

AI总结:

针对LLMs和RAG方法因概念簇过载而遗漏罕见生物医学知识的问题,提出利用知识图谱下采样的检索方法,其性能约为传统方法两倍,且混合模型表现更优。

摘要:

大型语言模型(LLMs)正在改变信息检索的方式,大量知识通过自然语言对话被总结和呈现。然而,LLMs倾向于突出训练集中最常见的信息片段,而忽略罕见信息。在生物医学研究领域,最新发现对学术界和工业界参与者至关重要,却因不断增长的文献语料库的庞杂而被掩盖(即信息过载问题)。利用LLMs揭示生物医学实体(例如药物、基因、疾病)之间的新关联,成为了一项捕获生物医学科学产出长尾知识的挑战。为克服这一挑战,检索增强生成(RAG)被提出,通过使用从外部数据集检索到的上下文来增强提示,以缓解LLMs的一些缺陷。RAG方法通常通过对文本嵌入进行最大相似性搜索来选择上下文。在本研究中,我们表明,由于生物医学文献中存在过度代表的概念簇,RAG方法遗漏了大量相关信息。我们引入了一种新颖的信息检索方法,该方法利用知识图谱对这些簇进行下采样,以缓解信息过载问题。在精确率和召回率方面,其检索性能大约是嵌入相似度替代方案的两倍。最后,我们证明,嵌入相似度和知识图谱检索方法可以有利地结合成一个混合模型,该模型优于两者,从而为生物医学问答模型带来潜在的改进。

英文摘要:

Large language models (LLMs) are transforming the way information is retrieved with vast amounts of knowledge being summarized and presented via natural language conversations. Yet, LLMs are prone to highlight the most frequently seen pieces of information from the training set and to neglect the rare ones. In the field of biomedical research, latest discoveries are key to academic and industrial actors and are obscured by the abundance of an ever-increasing literature corpus (the information overload problem). Surfacing new associations between biomedical entities, e.g., drugs, genes, diseases, with LLMs becomes a challenge of capturing the long-tail knowledge of the biomedical scientific production. To overcome this challenge, Retrieval Augmented Generation (RAG) has been proposed to alleviate some of the shortcomings of LLMs by augmenting the prompts with context retrieved from external datasets. RAG methods typically select the context via maximum similarity search over text embeddings. In this study, we show that RAG methods leave out a significant proportion of relevant information due to clusters of over-represented concepts in the biomedical literature. We introduce a novel information-retrieval method that leverages a knowledge graph to downsample these clusters and mitigate the information overload problem. Its retrieval performance is about twice better than embedding similarity alternatives on both precision and recall. Finally, we demonstrate that both embedding similarity and knowledge graph retrieval methods can be advantageously combined into a hybrid model that outperforms both, enabling potential improvements to biomedical question-answering models.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑