Split-NER: Named Entity Recognition via Two Question-Answering-based Classifications

Jatin Arora, Youngja Park


Abstract
In this work, we address the NER problem by splitting it into two logical sub-tasks: (1) Span Detection which simply extracts entity mention spans irrespective of entity type; (2) Span Classification which classifies the spans into their entity types. Further, we formulate both sub-tasks as question-answering (QA) problems and produce two leaner models which can be optimized separately for each sub-task. Experiments with four cross-domain datasets demonstrate that this two-step approach is both effective and time efficient. Our system, SplitNER outperforms baselines on OntoNotes5.0, WNUT17 and a cybersecurity dataset and gives on-par performance on BioNLP13CG. In all cases, it achieves a significant reduction in training time compared to its QA baseline counterpart. The effectiveness of our system stems from fine-tuning the BERT model twice, separately for span detection and classification. The source code can be found at https://github.com/c3sr/split-ner.
Anthology ID:
2023.acl-short.36
Volume:
Proceedings of the 61st Annual Meeting of the Association for Computational Linguistics (Volume 2: Short Papers)
Month:
July
Year:
2023
Address:
Toronto, Canada
Editors:
Anna Rogers, Jordan Boyd-Graber, Naoaki Okazaki
Venue:
ACL
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
416–426
Language:
URL:
https://aclanthology.org/2023.acl-short.36
DOI:
10.18653/v1/2023.acl-short.36
Bibkey:
Cite (ACL):
Jatin Arora and Youngja Park. 2023. Split-NER: Named Entity Recognition via Two Question-Answering-based Classifications. In Proceedings of the 61st Annual Meeting of the Association for Computational Linguistics (Volume 2: Short Papers), pages 416–426, Toronto, Canada. Association for Computational Linguistics.
Cite (Informal):
Split-NER: Named Entity Recognition via Two Question-Answering-based Classifications (Arora & Park, ACL 2023)
Copy Citation:
PDF:
https://aclanthology.org/2023.acl-short.36.pdf
Video:
 https://aclanthology.org/2023.acl-short.36.mp4