Named Entity Recognition as Structured Span Prediction

Urchade Zaratiana, Nadi Tomeh, Pierre Holat, Thierry Charnois


Abstract
Named Entity Recognition (NER) is an important task in Natural Language Processing with applications in many domains. While the dominant paradigm of NER is sequence labelling, span-based approaches have become very popular in recent times but are less well understood. In this work, we study different aspects of span-based NER, namely the span representation, learning strategy, and decoding algorithms to avoid span overlap. We also propose an exact algorithm that efficiently finds the set of non-overlapping spans that maximizes a global score, given a list of candidate spans. We performed our study on three benchmark NER datasets from different domains. We make our code publicly available at https://github.com/urchade/span-structured-prediction.
Anthology ID:
2022.umios-1.1
Volume:
Proceedings of the Workshop on Unimodal and Multimodal Induction of Linguistic Structures (UM-IoS)
Month:
December
Year:
2022
Address:
Abu Dhabi, United Arab Emirates (Hybrid)
Editors:
Wenjuan Han, Zilong Zheng, Zhouhan Lin, Lifeng Jin, Yikang Shen, Yoon Kim, Kewei Tu
Venue:
UM-IoS
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
1–10
Language:
URL:
https://aclanthology.org/2022.umios-1.1
DOI:
10.18653/v1/2022.umios-1.1
Bibkey:
Cite (ACL):
Urchade Zaratiana, Nadi Tomeh, Pierre Holat, and Thierry Charnois. 2022. Named Entity Recognition as Structured Span Prediction. In Proceedings of the Workshop on Unimodal and Multimodal Induction of Linguistic Structures (UM-IoS), pages 1–10, Abu Dhabi, United Arab Emirates (Hybrid). Association for Computational Linguistics.
Cite (Informal):
Named Entity Recognition as Structured Span Prediction (Zaratiana et al., UM-IoS 2022)
Copy Citation:
PDF:
https://aclanthology.org/2022.umios-1.1.pdf