A Frustratingly Easy Approach for Entity and Relation Extraction

Zexuan Zhong, Danqi Chen


Abstract
End-to-end relation extraction aims to identify named entities and extract relations between them. Most recent work models these two subtasks jointly, either by casting them in one structured prediction framework, or performing multi-task learning through shared representations. In this work, we present a simple pipelined approach for entity and relation extraction, and establish the new state-of-the-art on standard benchmarks (ACE04, ACE05 and SciERC), obtaining a 1.7%-2.8% absolute improvement in relation F1 over previous joint models with the same pre-trained encoders. Our approach essentially builds on two independent encoders and merely uses the entity model to construct the input for the relation model. Through a series of careful examinations, we validate the importance of learning distinct contextual representations for entities and relations, fusing entity information early in the relation model, and incorporating global context. Finally, we also present an efficient approximation to our approach which requires only one pass of both entity and relation encoders at inference time, achieving an 8-16× speedup with a slight reduction in accuracy.
Anthology ID:
2021.naacl-main.5
Volume:
Proceedings of the 2021 Conference of the North American Chapter of the Association for Computational Linguistics: Human Language Technologies
Month:
June
Year:
2021
Address:
Online
Venue:
NAACL
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
50–61
Language:
URL:
https://aclanthology.org/2021.naacl-main.5
DOI:
10.18653/v1/2021.naacl-main.5
Bibkey:
Copy Citation:
PDF:
https://aclanthology.org/2021.naacl-main.5.pdf
Code
 princeton-nlp/PURE
Data
ACE 2004ACE 2005SciERC