RS-TTS: A Novel Joint Entity and Relation Extraction Model

Abstract

Joint extraction of entity and relation is a basic task in the field of natural language processing. Existing methods have achieved good result, but there are still some limitations, such as span-based extraction cannot solve overlapping problems well, and redundant relation calculation leads to many invalid operations. To solve these problems, we propose a novel RelationSpecific Triple Tagging and Scoring Model (RS-TTS) for the joint extraction of entity and relation. Specifically, the model is composed of three parts: we use a relation judgment module to predict all potential relations to prevent computational redundancy; then a boundary smoothing mechanism is introduced to the entity pair extraction, which reallocates the probability of the ground truth entity to its surrounding tokens, thus preventing the model from being overconfident; finally, an efficient tagging and scoring strategy is used to decode entity. Extensive experiments show that our model performs better than the state-of-the-art baseline on the public benchmark dataset. F1-scores on the four datasets are improved, especially on WebNLG and WebNLG∗, which are improved by 1.7 and 1.1 respectively.