SDA: Simple Discrete Augmentation for Contrastive Sentence Representation Learning

Dongsheng Zhu, Zhenyu Mao, Jinghui Lu, Rui Zhao, Fei Tan


Abstract
Contrastive learning has recently achieved compelling performance in unsupervised sentence representation. As an essential element, data augmentation protocols, however, have not been well explored. The pioneering work SimCSE resorting to a simple dropout mechanism (viewed as continuous augmentation) surprisingly dominates discrete augmentations such as cropping, word deletion, and synonym replacement as reported. To understand the underlying rationales, we revisit existing approaches and attempt to hypothesize the desiderata of reasonable data augmentation methods: balance of semantic consistency and expression diversity. We then develop three simple yet effective discrete sentence augmentation schemes: punctuation insertion, modal verbs, and double negation. They act as minimal noises at lexical level to produce diverse forms of sentences. Furthermore, standard negation is capitalized on to generate negative samples for alleviating feature suppression involved in contrastive learning. We experimented extensively with semantic textual similarity on diverse datasets. The results support the superiority of the proposed methods consistently. Our key code is available at https://github.com/Zhudongsheng75/SDA
Anthology ID:
2024.lrec-main.1260
Volume:
Proceedings of the 2024 Joint International Conference on Computational Linguistics, Language Resources and Evaluation (LREC-COLING 2024)
Month:
May
Year:
2024
Address:
Torino, Italia
Editors:
Nicoletta Calzolari, Min-Yen Kan, Veronique Hoste, Alessandro Lenci, Sakriani Sakti, Nianwen Xue
Venues:
LREC | COLING
SIG:
Publisher:
ELRA and ICCL
Note:
Pages:
14459–14471
Language:
URL:
https://aclanthology.org/2024.lrec-main.1260
DOI:
Bibkey:
Cite (ACL):
Dongsheng Zhu, Zhenyu Mao, Jinghui Lu, Rui Zhao, and Fei Tan. 2024. SDA: Simple Discrete Augmentation for Contrastive Sentence Representation Learning. In Proceedings of the 2024 Joint International Conference on Computational Linguistics, Language Resources and Evaluation (LREC-COLING 2024), pages 14459–14471, Torino, Italia. ELRA and ICCL.
Cite (Informal):
SDA: Simple Discrete Augmentation for Contrastive Sentence Representation Learning (Zhu et al., LREC-COLING 2024)
Copy Citation:
PDF:
https://aclanthology.org/2024.lrec-main.1260.pdf