Distantly-Supervised Joint Entity and Relation Extraction with Noise-Robust Learning
Joint entity and relation extraction is a process that identifies entity pairs and their relations using a single model. We focus on the problem of training these models on distantly-labeled data, which is generated by aligning entity mentions in a text corpus with their corresponding entity and relation types in a knowledge base. One key challenge here is the presence of noisy labels, which arises from both entity and relation annotations, and significantly impair the effectiveness of supervised learning applications. However, existing research primarily addresses only one type of noise, thereby limiting the effectiveness of noise reduction. To fill this gap, we introduce a new noise-robust approach, that 1)~incorporates a pre-trained GPT-2 into a sequence tagging scheme for simultaneous entity and relation detection, and 2)~employs a noise-robust learning framework which includes a new loss function that penalizes inconsistency with both significant relation patterns and entity-relation dependencies, as well as a self-adaptive learning step that iteratively selects and trains on high-quality instances. Experiments on two datasets show that our method outperforms the existing state-of-the-art methods in both joint extraction performance and noise reduction effect.
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