Abstract
Event extraction is a fundamental task in information extraction. Most previous approaches typically transform event extraction into two subtasks: trigger classification and argument classification, and solve them via classification-based methods, which suffer from some inherent drawbacks. To overcome these issues, in this paper, we propose a novel event extraction model Seq2EG by first formulating event extraction as an event graph parsing problem, and then exploiting a pre-trained sequence-to-sequence (seq2seq) model to transduce an input sentence into an accurate event graph without the need for trigger words. Based on the generative event graph parsing formulation, our model Seq2EG can explicitly model the multiple event correlations and argument sharing and can naturally incorporate some graph-structured features and the rich semantic information conveyed by the labels of event types and argument roles. Extensive experimental results on the public ACE2005 dataset show that our approach outperforms all previous state-of-the-art models for event extraction by a large margin, respectively, obtaining an improvement of 3.4% F1 score for event detection and an improvement of 4.7% F1 score for argument classification over the best baselines.
Similar content being viewed by others
Notes
The source code will be publicly released upon acceptance.
References
Srihari RK, Li W (2000) A question answering system supported by information extraction. In: Sixth applied natural language processing conference, pp 166–172
Berant J, Srikumar V, Chen PC, Vander Linden A, Harding B, Huang B, Clark P, Manning CD (2014) Modeling biological processes for reading comprehension. In: Proceedings of the 2014 conference on empirical methods in natural language processing (EMNLP), pp 1499–1510
Grishman R, Westbrook D, Meyers A (2005) Nyu’s english ace 2005 system description. ACE 5
Chen Y, Xu L, Liu K, Zeng D, Zhao J (2015) Event extraction via dynamic multi-pooling convolutional neural networks. In: Proceedings of the 53rd annual meeting of the association for computational linguistics and the 7th international joint conference on natural language processing (ACL-IJCNLP), pp 167–176
Nguyen TH, Cho K, Grishman R (2016) Joint event extraction via recurrent neural networks. In: Proceedings of the 2016 conference of the North American chapter of the association for computational linguistics: human language technologies (NAACL-HLT)
Sha L, Qian F, Chang B, Sui Z (2018) Jointly extracting event triggers and arguments by dependency-bridge RNN and tensor-based argument interaction. In: Proceedings of the AAAI conference on artificial intelligence, vol 32
Chen Y, Yang H, Liu K, Zhao J, Jia Y (2018) Collective event detection via a hierarchical and bias tagging networks with gated multi-level attention mechanisms. In: Proceedings of the 2018 conference on empirical methods in natural language processing (EMNLP), pp 1267–1276
Li Q, Ji H, Huang L (2013) Joint event extraction via structured prediction with global features. In: Proceedings of the 51st annual meeting of the association for computational linguistics (ACL), pp 73–82
Nguyen TH, Grishman R (2018) Graph convolutional networks with argument-aware pooling for event detection. In: Proceedings of the AAAI conference on artificial intelligence, vol 32
Liu X, Luo Z, Huang H (2018) Jointly multiple events extraction via attention-based graph information aggregation. In: Proceedings of the 2018 conference on empirical methods in natural language processing (EMNLP), pp 1247–1256
Yan H, Jin X, Meng X, Guo J, Cheng X (2019) Event detection with multi-order graph convolution and aggregated attention. In: Proceedings of the 2019 conference on empirical methods in natural language processing and the 9th international joint conference on natural language processing (EMNLP-IJCNLP), pp 5766–5770
Lai VD, Nguyen TN, Nguyen TH (2020) Event detection: gate diversity and syntactic importance scores for graph convolution neural networks. In: Proceedings of the 2020 conference on empirical methods in natural language processing (EMNLP), pp 5405–5411
Li F, Peng W, Chen Y, Wang Q, Pan L, Lyu Y, Zhu Y (2020) Event extraction as multi-turn question answering. In: Findings of the association for computational linguistics: EMNLP 2020. Association for Computational Linguistics, pp 829–838
Tong M, Xu B, Wang S, Cao Y, Hou L, Li J, Xie J (2020) Improving event detection via open-domain trigger knowledge. In: Proceedings of the 58th annual meeting of the association for computational linguistics (ACL), pp 5887–5897
Liu S, Li Y, Zhang F, Yang T, Zhou X (2019) Event detection without triggers. In: Proceedings of the 2019 conference of the North American chapter of the association for computational linguistics: human language technologies (NAACL-HLT), pp 735–744
Xie J, Sun H, Zhou J, Qu W, Dai X (2021) Event detection as graph parsing. In: Findings of the association for computational linguistics: ACL-IJCNLP, pp 1630–1640
Rajpurkar P, Jia R, Liang P (2018) Know what you don’t know: unanswerable questions for SQuAD. In: Proceedings of the 56th annual meeting of the association for computational linguistics (ACL), pp 784–789
Joshi M, Choi E, Weld DS, Zettlemoyer L (2017) TriviaQA: a large scale distantly supervised challenge dataset for reading comprehension. In: Proceedings of the 55th annual meeting of the association for computational linguistics (ACL), pp 1601–1611
Du X, Cardie C (2020) Event extraction by answering (almost) natural questions. In: Proceedings of the 2020 conference on empirical methods in natural language processing (EMNLP), pp 671–683
Liu J, Chen Y, Liu K, Bi W, Liu X (2020) Event extraction as machine reading comprehension. In: Proceedings of the 2020 conference on empirical methods in natural language processing (EMNLP), pp 1641–1651
Lu Y, Lin H, Xu J, Han X, Tang J, Li A, Sun L, Liao M, Chen S (2021) Text2Event: Controllable sequence-to-structure generation for end-to-end event extraction. In: Proceedings of the 59th annual meeting of the association for computational linguistics and the 11th international joint conference on natural language processing (ACL-IJCNLP)
Wadden D, Wennberg U, Luan Y, Hajishirzi H (2019) Entity, relation, and event extraction with contextualized span representations. In: Proceedings of the 2019 conference on empirical methods in natural language processing and the 9th international joint conference on natural language processing (EMNLP-IJCNLP)
Du X, Rush AM, Cardie C (2021) GRIT: generative role-filler transformers for document-level event entity extraction. In: Proceedings of the 16th conference of the European chapter of the association for computational linguistics (EACL), pp 634–644
Li Z, Cai J, He S, Zhao H (2014) Seq2seq dependency parsing. In: Proceedings of the 27th international conference on computational linguistics. Association for Computational Linguistics, pp 3203–3214
Zhang S, Ma X, Duh K, Van Durme B (2019) AMR parsing as sequence-to-graph transduction. In: Proceedings of the 57th annual meeting of the association for computational linguistics, pp 80–94
Blloshmi R, Bevilacqua M, Fabiano E, Caruso V, Navigli R (2021) SPRING goes online: end-to-end AMR parsing and generation. In: Proceedings of the 2021 conference on empirical methods in natural language processing: system demonstrations, pp 134–142
Barnes J, Kurtz R, Oepen S, Øvrelid L, Velldal E (2021) Structured sentiment analysis as dependency graph parsing. 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), pp 3387–3402
Qiu L, Liang Y, Zhao Y, Lu P, Peng B, Yu Z, Wu YN, Zhu SC (2021) SocAoG: incremental graph parsing for social relation inference in dialogues. 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), pp 658–670
Paolini G, Athiwaratkun B, Krone J, Ma J, Achille A, Anubhai R, Santos CN, Xiang B, Soatto S (2021) Structured prediction as translation between augmented natural languages. In: 9th international conference on learning representations, ICLR 2021
Devlin J, Chang MW, Lee K, Toutanova K (2019) BERT: pre-training of deep bidirectional transformers for language understanding. In: Proceedings of the 2019 conference of the North American chapter of the association for computational linguistics: human language technologies (NAACL-HLT), pp 4171–4186
Song K, Tan X, Qin T, Lu J, Liu TY (2019) MASS: masked sequence to sequence pre-training for language generation. CoRR. arXiv:1905.02450
Wang X, Han X, Liu Z, Sun M, Li P (2019) Adversarial training for weakly supervised event detection. In: Proceedings of the 2019 conference of the North American chapter of the association for computational linguistics: human language technologies (NAACL-HLT), pp 998–1008
Zhang J, Zhao Y, Saleh M, Liu P (2019) PEGASUS: pre-training with extracted gap-sentences for abstractive summarization. CoRR. arXiv:1912.08777
Lewis M, Liu Y, Goyal N, Ghazvininejad M, Mohamed A, Levy O, Stoyanov V, Zettlemoyer L (2002) BART: denoising sequence-to-sequence pre-training for natural language generation, translation, and comprehension. In: Proceedings of the 58th annual meeting of the association for computational linguistics (ACL), pp 7871–7880
Raffel C, Shazeer N, Roberts A, Lee K, Narang S, Matena M, Zhou Y, Li W, Liu PJ (2019) Exploring the limits of transfer learning with a unified text-to-text transformer. CoRR. arXiv:1910.10683
Bahdanau D, Cho K, Bengio Y (2014) Neural machine translation by jointly learning to align and translate. arXiv preprint arXiv:1409.0473
Vaswani A, Shazeer N, Parmar N, Uszkoreit J, Jones L, Gomez AN, Kaiser Ł, Polosukhin I (2017) Attention is all you need. In: Advances in neural information processing systems (NIPS), pp 5998–6008
Ji H, Grishman R (2008) Refining event extraction through cross-document inference. In: Proceedings of ACL-08: HLT, pp 254–262
Liao S, Grishman R (2010) Using document level cross-event inference to improve event extraction. In: Proceedings of the 48th annual meeting of the association for computational linguistics (ACL), pp 789–797
Lu Y, Lin H, Han X, Sun L (2019) Distilling discrimination and generalization knowledge for event detection via delta-representation learning. In: Proceedings of the 57th annual meeting of the association for computational linguistics (ACL), pp 4366–4376
Chen Y, Liu S, Zhang X, Liu K, Zhao J (2017) Automatically labeled data generation for large scale event extraction. In: Proceedings of the 55th annual meeting of the association for computational linguistics (ACL), pp 409–419
He H, Sun X (2017) A unified model for cross-domain and semi-supervised named entity recognition in Chinese social media. In: Proceedings of the AAAI conference on artificial intelligence, vol 31
Acknowledgements
We thank all reviewers for the valuable comments. This work is supported by project 62277031 under the National Science Foundation of China and project 22AYY013 under the National Social Science Foundation of China.
Author information
Authors and Affiliations
Corresponding author
Additional information
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Rights and permissions
Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.
About this article
Cite this article
Sun, H., Zhou, J., Kong, L. et al. Seq2EG: a novel and effective event graph parsing approach for event extraction. Knowl Inf Syst 65, 4273–4294 (2023). https://doi.org/10.1007/s10115-023-01898-3
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10115-023-01898-3