Biomedical Event Extraction with Hierarchical Knowledge Graphs

Kung-Hsiang Huang, Mu Yang, Nanyun Peng


Abstract
Biomedical event extraction is critical in understanding biomolecular interactions described in scientific corpus. One of the main challenges is to identify nested structured events that are associated with non-indicative trigger words. We propose to incorporate domain knowledge from Unified Medical Language System (UMLS) to a pre-trained language model via Graph Edge-conditioned Attention Networks (GEANet) and hierarchical graph representation. To better recognize the trigger words, each sentence is first grounded to a sentence graph based on a jointly modeled hierarchical knowledge graph from UMLS. The grounded graphs are then propagated by GEANet, a novel graph neural networks for enhanced capabilities in inferring complex events. On BioNLP 2011 GENIA Event Extraction task, our approach achieved 1.41% F1 and 3.19% F1 improvements on all events and complex events, respectively. Ablation studies confirm the importance of GEANet and hierarchical KG.
Anthology ID:
2020.findings-emnlp.114
Volume:
Findings of the Association for Computational Linguistics: EMNLP 2020
Month:
November
Year:
2020
Address:
Online
Editors:
Trevor Cohn, Yulan He, Yang Liu
Venue:
Findings
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
1277–1285
Language:
URL:
https://aclanthology.org/2020.findings-emnlp.114
DOI:
10.18653/v1/2020.findings-emnlp.114
Bibkey:
Cite (ACL):
Kung-Hsiang Huang, Mu Yang, and Nanyun Peng. 2020. Biomedical Event Extraction with Hierarchical Knowledge Graphs. In Findings of the Association for Computational Linguistics: EMNLP 2020, pages 1277–1285, Online. Association for Computational Linguistics.
Cite (Informal):
Biomedical Event Extraction with Hierarchical Knowledge Graphs (Huang et al., Findings 2020)
Copy Citation:
PDF:
https://aclanthology.org/2020.findings-emnlp.114.pdf
Optional supplementary material:
 2020.findings-emnlp.114.OptionalSupplementaryMaterial.zip
Video:
 https://slideslive.com/38940169
Code
 PlusLabNLP/GEANet-BioMed-Event-Extraction
Data
GENIA