Salient Span Masking for Temporal Understanding
Jeremy R. Cole, Aditi Chaudhary, Bhuwan Dhingra, Partha Talukdar
Abstract
Salient Span Masking (SSM) has shown itself to be an effective strategy to improve closed-book question answering performance. SSM extends general masked language model pretraining by creating additional unsupervised training sentences that mask a single entity or date span, thus oversampling factual information. Despite the success of this paradigm, the span types and sampling strategies are relatively arbitrary and not widely studied for other tasks. Thus, we investigate SSM from the perspective of temporal tasks, where learning a good representation of various temporal expressions is important. To that end, we introduce Temporal Span Masking (TSM) intermediate training. First, we find that SSM alone improves the downstream performance on three temporal tasks by an avg. +5.8 points. Further, we are able to achieve additional improvements (avg. +0.29 points) by adding the TSM task. These comprise the new best reported results on the targeted tasks. Our analysis suggests that the effectiveness of SSM stems from the sentences chosen in the training data rather than the mask choice: sentences with entities frequently also contain temporal expressions. Nonetheless, the additional targeted spans of TSM can still improve performance, especially in a zero-shot context.- Anthology ID:
- 2023.eacl-main.222
- Volume:
- Proceedings of the 17th Conference of the European Chapter of the Association for Computational Linguistics
- Month:
- May
- Year:
- 2023
- Address:
- Dubrovnik, Croatia
- Editors:
- Andreas Vlachos, Isabelle Augenstein
- Venue:
- EACL
- SIG:
- Publisher:
- Association for Computational Linguistics
- Note:
- Pages:
- 3052–3060
- Language:
- URL:
- https://aclanthology.org/2023.eacl-main.222
- DOI:
- 10.18653/v1/2023.eacl-main.222
- Cite (ACL):
- Jeremy R. Cole, Aditi Chaudhary, Bhuwan Dhingra, and Partha Talukdar. 2023. Salient Span Masking for Temporal Understanding. In Proceedings of the 17th Conference of the European Chapter of the Association for Computational Linguistics, pages 3052–3060, Dubrovnik, Croatia. Association for Computational Linguistics.
- Cite (Informal):
- Salient Span Masking for Temporal Understanding (Cole et al., EACL 2023)
- PDF:
- https://preview.aclanthology.org/revert-3132-ingestion-checklist/2023.eacl-main.222.pdf