Few-shot relation classification by context attention-based prototypical networks with BERT

Abstract

Human-computer interaction under the cloud computing platform is very important, but the semantic gap will limit the performance of interaction. It is necessary to understand the semantic information in various scenarios. Relation classification (RC) is an import method to implement the description of semantic formalization. It aims at classifying a relation between two specified entities in a sentence. Existing RC models typically rely on supervised learning and distant supervision. Supervised learning requires large-scale supervised training datasets, which are not readily available. Distant supervision introduces noise, and many long-tail relations still suffer from data sparsity. Few-shot learning, which is widely used in image classification, is an effective method for overcoming data sparsity. In this paper, we apply few-shot learning to a relation classification task. However, not all instances contribute equally to the relation prototype in a text-based few-shot learning scenario, which can cause the prototype deviation problem. To address this problem, we propose context attention-based prototypical networks. We design context attention to highlight the crucial instances in the support set to generate a satisfactory prototype. Besides, we also explore the application of a recently popular pre-trained language model to few-shot relation classification tasks. The experimental results demonstrate that our model outperforms the state-of-the-art models and converges faster.