CDER: Collaborative Evidence Retrieval for Document-level Relation Extraction
Khai Phan Tran, Xue Li
TL;DR
This work tackles document-level relation extraction (DocRE) with a focus on evidence retrieval (ER). It introduces CDER, a collaborative ER framework that builds a document-level bipartite graph with three sub-graphs and employs Entity Pair-aware GATs (EP-GATs) to model cross-pair collaboration and evidence dynamics. Key innovations include a dynamic Entity Pair sub-graph $G_{PP}$ guided by relation similarity, EP-GAT layers for $G_{PS}$ and $G_{PP}$, and a focal loss to handle severe evidence imbalance, which together yield strong ER performance and improve downstream DocRE. Experiments on DocRED show that CDER not only achieves state-of-the-art ER metrics but also provides substantial gains when plugged into existing DocRE systems, underscoring its practical impact for robust, scalable information extraction.
Abstract
Document-level Relation Extraction (DocRE) involves identifying relations between entities across multiple sentences in a document. Evidence sentences, crucial for precise entity pair relationships identification, enhance focus on essential text segments, improving DocRE performance. However, existing evidence retrieval systems often overlook the collaborative nature among semantically similar entity pairs in the same document, hindering the effectiveness of the evidence retrieval task. To address this, we propose a novel evidence retrieval framework, namely CDER. CDER employs an attentional graph-based architecture to capture collaborative patterns and incorporates a dynamic sub-structure for additional robustness in evidence retrieval. Experimental results on the benchmark DocRE dataset show that CDER not only excels in the evidence retrieval task but also enhances overall performance of existing DocRE system.
