2*n is better than n2: Decomposing Event Coreference Resolution into Two Tractable Problems

Shafiuddin Rehan Ahmed, Abhijnan Nath, James H. Martin, Nikhil Krishnaswamy


Abstract
Event Coreference Resolution (ECR) is the task of linking mentions of the same event either within or across documents. Most mention pairs are not coreferent, yet many that are coreferent can be identified through simple techniques such as lemma matching of the event triggers or the sentences in which they appear. Existing methods for training coreference systems sample from a largely skewed distribution, making it difficult for the algorithm to learn coreference beyond surface matching. Additionally, these methods are intractable because of the quadratic operations needed. To address these challenges, we break the problem of ECR into two parts: a) a heuristic to efficiently filter out a large number of non-coreferent pairs, and b) a training approach on a balanced set of coreferent and non-coreferent mention pairs. By following this approach, we show that we get comparable results to the state of the art on two popular ECR datasets while significantly reducing compute requirements. We also analyze the mention pairs that are “hard” to accurately classify as coreferent or non-coreferentcode repo: github.com/ahmeshaf/lemma_ce_coref.
Anthology ID:
2023.findings-acl.100
Original:
2023.findings-acl.100v1
Version 2:
2023.findings-acl.100v2
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:
1569–1583
Language:
URL:
https://aclanthology.org/2023.findings-acl.100
DOI:
10.18653/v1/2023.findings-acl.100
Bibkey:
Cite (ACL):
Shafiuddin Rehan Ahmed, Abhijnan Nath, James H. Martin, and Nikhil Krishnaswamy. 2023. 2*n is better than n2: Decomposing Event Coreference Resolution into Two Tractable Problems. In Findings of the Association for Computational Linguistics: ACL 2023, pages 1569–1583, Toronto, Canada. Association for Computational Linguistics.
Cite (Informal):
2*n is better than n2: Decomposing Event Coreference Resolution into Two Tractable Problems (Ahmed et al., Findings 2023)
Copy Citation:
PDF:
https://aclanthology.org/2023.findings-acl.100.pdf