Incorporating Part of Speech Information in span representation for Named Entity Recognition

Abstract

Named Entity Recognition (NER) plays a pivotal role in knowledge extraction and improving the intelligence of edge computing. The effectiveness of span-based NER models predominantly depends on the representation of spans. Existing methods primarily utilize semantic features to represent spans, often neglecting other vital information. This paper proposes a method incorporating Part of Speech (POS) information into span representations to overcome this limitation. Central to this methodology is a span POS encoder designed to extract the POS feature of spans. For migrating the method to edge devices, this paper introduces a fast span POS encoder, which significantly reduces the time complexity of POS feature extraction. Building upon this innovation, a span-based NER model named IPSI (Incorporating Part of Speech Information in span representation) is developed, exhibiting outstanding performance on nested and flat datasets. Comparison the original and fast span POS encoders reveals that while the fast encoder slightly compromises performance, it markedly accelerates the training and inference processes. Finally, through a series of experiments and sample analyses, this article explores the intrinsic mechanism through which the span POS feature influences entity recognition and further illustrates the importance of the POS feature.