Prompt-Based Metric Learning for Few-Shot NER

Yanru Chen, Yanan Zheng, Zhilin Yang


Abstract
Few-shot named entity recognition (NER) targets generalizing to unseen labels and/or domains with few labeled examples. Existing metric learning methods compute token-level similarities between query and support sets, but are not able to fully incorporate label semantics into modeling. To address this issue, we propose a simple method to largely improve metric learning for NER: 1) multiple prompt schemas are designed to enhance label semantics; 2) we propose a novel architecture to effectively combine multiple prompt-based representations. Empirically, our method achieves new state-of-the-art (SOTA) results under 16 of the 18 considered settings, substantially outperforming the previous SOTA by an average of 9.12% and a maximum of 34.51% in relative gains of micro F1.
Anthology ID:
2023.findings-acl.451
Volume:
Findings of the Association for Computational Linguistics: ACL 2023
Month:
July
Year:
2023
Address:
Toronto, Canada
Editors:
Anna Rogers, Jordan Boyd-Graber, Naoaki Okazaki
Venue:
Findings
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
7199–7212
Language:
URL:
https://aclanthology.org/2023.findings-acl.451
DOI:
10.18653/v1/2023.findings-acl.451
Bibkey:
Cite (ACL):
Yanru Chen, Yanan Zheng, and Zhilin Yang. 2023. Prompt-Based Metric Learning for Few-Shot NER. In Findings of the Association for Computational Linguistics: ACL 2023, pages 7199–7212, Toronto, Canada. Association for Computational Linguistics.
Cite (Informal):
Prompt-Based Metric Learning for Few-Shot NER (Chen et al., Findings 2023)
Copy Citation:
PDF:
https://aclanthology.org/2023.findings-acl.451.pdf