Due to the absence of explicit connectives, implicit discourse relation recognition (IDRR) remains a challenging task in discourse analysis. The critical step for IDRR is to learn high-quality discourse relation representations between two arguments. Recent methods tend to integrate the whole hierarchical information of senses into discourse relation representations for multi-level sense recognition. Nevertheless, they insufficiently incorporate the static hierarchical structure containing all senses (defined as global hierarchy), and ignore the hierarchical sense label sequence corresponding to each instance (defined as local hierarchy). For the purpose of sufficiently exploiting global and local hierarchies of senses to learn better discourse relation representations, we propose a novel GLobal and LOcal Hierarchy-aware Contrastive Framework (GLOF), to model two kinds of hierarchies with the aid of contrastive learning. Experimental results on the PDTB dataset demonstrate that our method remarkably outperforms the current state-of-the-art model at all hierarchical levels.

提出了一种新颖的全局和本地层次感知对比框架（GLOF），以通过对比学习来建模两种层次。该方法在PDTB数据集上显着优于当前最先进的模型，解决了暗示性篇章关系识别(IDRR)在篇章分析中的难题。

全局和局部基于层级感知的对比框架在隐式篇章关系识别中的应用