CE-GOCD: Central Entity-Guided Graph Optimization for Community Detection to Augment LLM Scientific Question Answering
Jiayin Lan, Jiaqi Li, Baoxin Wang, Ming Liu, Dayong Wu, Shijin Wang, Bing Qin, Guoping Hu
TL;DR
CE-GOCD addresses the challenge of robust scientific question answering with LLMs by explicitly modeling semantic substructures in a knowledge graph of academic papers. It introduces a title-centered pipeline: (i) subgraph retrieval using center entities and lexical cues, (ii) subgraph pruning and completion to uncover implicit relations, and (iii) title-guided community detection via modularity optimization to group thematically related papers. The method yields superior QA performance on NLP benchmarks and demonstrates domain generalizability to medical data, with ablations confirming the necessity of both subgraph optimization and community-level reasoning. The approach offers a principled way to augment LLM QA with structured, thematically coherent evidence across papers, enhancing accuracy and interpretability in scientific literature search and reasoning.
Abstract
Large Language Models (LLMs) are increasingly used for question answering over scientific research papers. Existing retrieval augmentation methods often rely on isolated text chunks or concepts, but overlook deeper semantic connections between papers. This impairs the LLM's comprehension of scientific literature, hindering the comprehensiveness and specificity of its responses. To address this, we propose Central Entity-Guided Graph Optimization for Community Detection (CE-GOCD), a method that augments LLMs' scientific question answering by explicitly modeling and leveraging semantic substructures within academic knowledge graphs. Our approach operates by: (1) leveraging paper titles as central entities for targeted subgraph retrieval, (2) enhancing implicit semantic discovery via subgraph pruning and completion, and (3) applying community detection to distill coherent paper groups with shared themes. We evaluated the proposed method on three NLP literature-based question-answering datasets, and the results demonstrate its superiority over other retrieval-augmented baseline approaches, confirming the effectiveness of our framework.
