Self-supervised Meta-Prompt Learning with Meta-Gradient Regularization for Few-shot Generalization

Kaihang Pan, Juncheng Li, Hongye Song, Jun Lin, Xiaozhong Liu, Siliang Tang


Abstract
Prompt tuning is a parameter-efficient method, which learns soft prompts and conditions frozen language models to perform specific downstream tasks. Though effective, prompt tuning under few-shot settings on the one hand heavily relies on a good initialization of soft prompts. On the other hand, it can easily overfit to few-shot training samples, thereby undermining generalizability. Existing works leverage pre-training or supervised meta-learning to initialize soft prompts but they fail to data-efficiently generalize to unseen downstream tasks. To address the above problems, this paper proposes a novel Self-sUpervised meta-Prompt learning framework with MEta-gradient Regularization for few-shot generalization (SUPMER). SUPMER leverages self-supervised meta-learning with a diverse set of well-designed meta-tasks to learn a universal prompt initialization for efficient adaptation using only unlabeled data. Additionally, it jointly meta-learns a gradient regularization function to transform raw gradients into a domain-generalizable direction, thus alleviating the problem of overfitting. Extensive experiments show that SUPMER achieves better performance for different few-shot downstream tasks, and also exhibits a stronger domain generalization ability. The code for SUPMER will be available at https://github.com/beepkh/SUPMER.
Anthology ID:
2023.findings-emnlp.75
Volume:
Findings of the Association for Computational Linguistics: EMNLP 2023
Month:
December
Year:
2023
Address:
Singapore
Editors:
Houda Bouamor, Juan Pino, Kalika Bali
Venue:
Findings
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
1059–1077
Language:
URL:
https://aclanthology.org/2023.findings-emnlp.75
DOI:
10.18653/v1/2023.findings-emnlp.75
Bibkey:
Cite (ACL):
Kaihang Pan, Juncheng Li, Hongye Song, Jun Lin, Xiaozhong Liu, and Siliang Tang. 2023. Self-supervised Meta-Prompt Learning with Meta-Gradient Regularization for Few-shot Generalization. In Findings of the Association for Computational Linguistics: EMNLP 2023, pages 1059–1077, Singapore. Association for Computational Linguistics.
Cite (Informal):
Self-supervised Meta-Prompt Learning with Meta-Gradient Regularization for Few-shot Generalization (Pan et al., Findings 2023)
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PDF:
https://aclanthology.org/2023.findings-emnlp.75.pdf
Video:
 https://aclanthology.org/2023.findings-emnlp.75.mp4