Document-level Event Extraction via Parallel Prediction Networks
Hang Yang, Dianbo Sui, Yubo Chen, Kang Liu, Jun Zhao, Taifeng Wang
Abstract
Document-level event extraction (DEE) is indispensable when events are described throughout a document. We argue that sentence-level extractors are ill-suited to the DEE task where event arguments always scatter across sentences and multiple events may co-exist in a document. It is a challenging task because it requires a holistic understanding of the document and an aggregated ability to assemble arguments across multiple sentences. In this paper, we propose an end-to-end model, which can extract structured events from a document in a parallel manner. Specifically, we first introduce a document-level encoder to obtain the document-aware representations. Then, a multi-granularity non-autoregressive decoder is used to generate events in parallel. Finally, to train the entire model, a matching loss function is proposed, which can bootstrap a global optimization. The empirical results on the widely used DEE dataset show that our approach significantly outperforms current state-of-the-art methods in the challenging DEE task. Code will be available at https://github.com/HangYang-NLP/DE-PPN.- Anthology ID:
- 2021.acl-long.492
- Volume:
- Proceedings of the 59th Annual Meeting of the Association for Computational Linguistics and the 11th International Joint Conference on Natural Language Processing (Volume 1: Long Papers)
- Month:
- August
- Year:
- 2021
- Address:
- Online
- Venues:
- ACL | IJCNLP
- SIG:
- Publisher:
- Association for Computational Linguistics
- Note:
- Pages:
- 6298–6308
- Language:
- URL:
- https://aclanthology.org/2021.acl-long.492
- DOI:
- 10.18653/v1/2021.acl-long.492
- Cite (ACL):
- Hang Yang, Dianbo Sui, Yubo Chen, Kang Liu, Jun Zhao, and Taifeng Wang. 2021. Document-level Event Extraction via Parallel Prediction Networks. In Proceedings of the 59th Annual Meeting of the Association for Computational Linguistics and the 11th International Joint Conference on Natural Language Processing (Volume 1: Long Papers), pages 6298–6308, Online. Association for Computational Linguistics.
- Cite (Informal):
- Document-level Event Extraction via Parallel Prediction Networks (Yang et al., ACL-IJCNLP 2021)
- PDF:
- https://preview.aclanthology.org/remove-xml-comments/2021.acl-long.492.pdf
- Code
- hangyang-nlp/de-ppn + additional community code
- Data
- ChFinAnn