Concepts benefit natural language understanding but are far from complete in existing knowledge graphs (KGs). Recently, pre-trained language models (PLMs) have been widely used in text-based concept extraction (CE). However, PLMs tend to mine the co-occurrence associations from massive corpus as pre-trained knowledge rather than the real causal effect between tokens. As a result, the pre-trained knowledge confounds PLMs to extract biased concepts based on spurious co-occurrence correlations, inevitably resulting in low precision. In this paper, through the lens of a Structural Causal Model (SCM), we propose equipping the PLM-based extractor with a knowledge-guided prompt as an intervention to alleviate concept bias. The prompt adopts the topic of the given entity from the existing knowledge in KGs to mitigate the spurious co-occurrence correlations between entities and biased concepts. Our extensive experiments on representative multilingual KG datasets justify that our proposed prompt can effectively alleviate concept bias and improve the performance of PLM-based CE models.The code has been released on https://github.com/siyuyuan/KPCE.

翻译：概念有助于自然语言理解，但现有知识图谱中的概念远不完整。近年来，预训练语言模型被广泛用于基于文本的概念提取。然而，预训练语言模型倾向于从海量语料中挖掘共现关联作为预训练知识，而非挖掘词元之间的真实因果效应。因此，预训练知识会混淆预训练语言模型，使其基于虚假的共现关联提取有偏概念，不可避免地导致精度低下。本文通过结构因果模型的视角，提出为基于预训练语言模型的抽取器配备知识引导提示作为干预手段，以缓解概念偏差。该提示利用知识图谱中现有知识对给定实体进行主题引导，从而缓解实体与有偏概念之间的虚假共现关联。我们在代表性多语言知识图谱数据集上的大量实验证明，本文提出的提示能有效缓解概念偏差，并提升基于预训练语言模型的概念提取模型性能。代码已发布于 https://github.com/siyuyuan/KPCE。