Efficient Document Retrieval with G-Retriever
Manthankumar Solanki
TL;DR
This work tackles efficient QA over textual graphs by replacing the PCST-based subgraph construction with an attention-driven retrieval mechanism and by encoding both node and edge attributes. It introduces an enhanced graph encoder with joint node-edge representations, followed by multi-head attention pooling and an improved projection layer to better align with Large Language Models. On WebQSP, the proposed approach achieves competitive, marginally better results than the previous G-Retriever, demonstrating improved context-aware retrieval and graph representations. The method advances practical, scalable retrieval for graph-structured QA by delivering stronger grounding and alignment with LLMs.
Abstract
Textual data question answering has gained significant attention due to its growing applicability. Recently, a novel approach leveraging the Retrieval-Augmented Generation (RAG) method was introduced, utilizing the Prize-Collecting Steiner Tree (PCST) optimization for sub-graph construction. However, this method focused solely on node attributes, leading to incomplete contextual understanding. In this paper, we propose an enhanced approach that replaces the PCST method with an attention-based sub-graph construction technique, enabling more efficient and context-aware retrieval. Additionally, we encode both node and edge attributes, leading to richer graph representations. Our method also incorporates an improved projection layer and multi-head attention pooling for better alignment with Large Language Models (LLMs). Experimental evaluations on the WebQSP dataset demonstrate that our approach is competitive and achieves marginally better results compared to the original method, underscoring its potential for more accurate question answering.
