Joint Entity and Relation Extraction with Span Pruning and Hypergraph
  Neural Networks
Zhaohui Yan Songlin Yang Wei Liu Kewei Tu
Entity and Relation Extraction (ERE) is an important task in information
extraction. Recent marker-based pipeline models achieve state-of-the-art
performance, but still suffer from the error propagation issue. Also, most of
current ERE models do not take into account higher-order interactions between
multiple entities and relations, while higher-order modeling could be
beneficial.In this work, we propose HyperGraph neural network for ERE
($\hgnn{}$), which is built upon the PL-marker (a state-of-the-art marker-based
pipleline model). To alleviate error propagation,we use a high-recall pruner
mechanism to transfer the burden of entity identification and labeling from the
NER module to the joint module of our model. For higher-order modeling, we
build a hypergraph, where nodes are entities (provided by the span pruner) and
relations thereof, and hyperedges encode interactions between two different
relations or between a relation and its associated subject and object entities.
We then run a hypergraph neural network for higher-order inference by applying
message passing over the built hypergraph. Experiments on three widely used
benchmarks (\acef{}, \ace{} and \scierc{}) for ERE task show significant
improvements over the previous state-of-the-art PL-marker.