Elamur Research⌕
☰
home / papers / 2020 / A Graph-based Model for Joint Chinese Word Segmentation and Dependency Parsing

A Graph-based Model for Joint Chinese Word Segmentation and Dependency Parsing

Paper · 2020 · Hang Yan, Xipeng Qiu and Xuanjing Huang

Summary

Chinese text has no explicit word boundaries, but dependency parsing works on words, so parsers usually run after a separate segmentation step. In this pipeline, segmentation mistakes carry over into parsing, and character-based pre-trained models such as BERT cannot be used directly. Earlier joint systems were transition-based. They faced huge search spaces, relied on approximate decoding and heavy feature design, and mostly handled only unlabeled parsing.

Yan, Qiu and Huang recast both tasks as a single character-level graph-based parsing problem. Characters inside a word attach to the next character through an "app" arc. Each word-level dependency is redrawn between the final characters of the two words. Representations from a BiLSTM or BERT encoder are passed to a scoring module built on biaffine attention (Dozat and Manning, 2017), which predicts arcs and labels with no need for POS tags.

On CTB-5, CTB-7 and CTB-9, the model reaches state-of-the-art results for both segmentation and dependency parsing and beats feature-rich joint baselines. With BERT, its parsing accuracy approaches that of parsers given gold segmentation.

Key points

  • Encoding scheme: segmentation becomes intra-word "app" arcs, and word dependencies link the last characters of the head and dependent words. A standard graph-based parser with maximum spanning tree decoding can then handle labeled parsing jointly with segmentation.
  • Data and code: experiments use CTB-5, CTB-7 and CTB-9 without any POS information. Code is released at github.com/fastnlp/JointCwsParser, built on fastNLP.
  • Motivation: pipeline systems reportedly reach only about 75–80% dependency scores (Kurita et al., 2017). Exact transition-based joint decoding costs O(n³) and has been limited to unlabeled parsing.
  • Error analysis vs. the pipeline: segmentation F1 differs by only about 0.1 points on average. However, the pipeline makes roughly 0.82 points more wrong-head errors, which the authors attribute to its sensitivity to segmentation and OOV errors. Joint-Multi-BERT cuts wrong-head errors substantially.
  • Ablation on CTB-5/CTB-7: removing bigram/trigram features was compared with removing pre-trained character embeddings. The no-n-gram variant scored about 0.16 lower in F1seg but about 0.95 higher in F1udep. The authors read this as evidence that the joint model resists error propagation.

Our summary of the paper, in our own words — not its text. The work belongs to its authors; read it at the links above.

 Institutions

 Fields, topics and concepts

Cite

Cite as Hang Yan, Xipeng Qiu and Xuanjing Huang. 2020. A Graph-based Model for Joint Chinese Word Segmentation and Dependency Parsing. Transactions of the Association for Computational Linguistics.

The paper itself, not this page. BibTeX from the library's record of the work. DOI 10.1162/tacl_a_00301

@article{yan2020graph,
  title = {{A Graph-based Model for Joint Chinese Word Segmentation and Dependency Parsing}},
  author = {Hang Yan, Xipeng Qiu and Xuanjing Huang},
  journal = {Transactions of the Association for Computational Linguistics},
  year = {2020},
  doi = {10.1162/tacl\_a\_00301},
  url = {https://doi.org/10.1162/tacl_a_00301}
}

References

36 references, 12 of them with a card of ours. ↗ leads to the work, «find» searches for one we have no id for yet.

  1. Dzmitry Bahdanau, Kyunghyun Cho, and Yoshua Bengio. 2015. Neural machine translation by jointly learning to align and translate. In 3rd International Conference on Learning Representations, ICLR 2015, San Diego, CA, USA, May 7–9, 2015, Conference Track Proceedings.
  2. Jun Hatori, Takuya Matsuzaki, Yusuke Miyao, and Jun’ichi Tsujii. 2012. Incremental joint approach to word segmentation, POS tagging, and dependency parsing in Chinese. In The 50th Annual Meeting of the Association for Computational Linguistics, Proceedings of the Conference, July 8–14, 2012, Jeju Is… find
  3. Xinchi Chen, Xipeng Qiu, and Xuanjing Huang. 2017. A feature-enriched neural model for joint Chinese word segmentation and part-of-speech tagging. In Proceedings of the Twenty-Sixth International Joint Conference on Artificial Intelligence, IJCAI 2017, Melbourne, Australia, August 19–25, 2017. find
  4. Sepp Hochreiter and Jürgen Schmidhuber. 1997. Long short-term memory. Neural Computation, 9(8):1735–1780. find
  5. Diederik P. Kingma and Jimmy Ba. 2015. Adam: A method for stochastic optimization. In 3rd International Conference on Learning Representations, ICLR 2015, San Diego, CA, USA, May 7–9, 2015, Conference Track Proceedings.
  6. Xinchi Chen, Xipeng Qiu, Chenxi Zhu, Pengfei Liu, and Xuanjing Huang. 2015. Long Short-Term Memory Neural Networks for Chinese Word Segmentation. In Proceedings of the 2015 Conference on Empirical Methods in Natural Language Processing, EMNLP 2015, Lisbon, Portugal, September 17–21, 2015.
  7. Eliyahu Kiperwasser and Yoav Goldberg. 2016. Simple and accurate dependency parsing using bidirectional LSTM feature representations. Transactions of the Association for Computational Linguistics TACL, 4:313–327.
  8. Yiming Cui, Wanxiang Che, Ting Liu, Bing Qin, Ziqing Yang, Shijin Wang, and Guoping Hu. 2019. Pre-training with whole word masking for Chinese BERT. CoRR, abs/1906.08101v2.
  9. Sandra Kübler, Ryan T. McDonald, and Joakim Nivre. 2009. Dependency Parsing. Synthesis Lectures on Human Language Technologies. Morgan & Claypool Publishers. find
  10. Jacob Devlin, Ming-Wei Chang, Kenton Lee, and Kristina Toutanova. 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,…
  11. Proceedings of the 2004 Conference on Empirical Methods in Natural Language Processing, EMNLP 2004, A meeting of SIGDAT, a Special Interest Group of the ACL, held in conjunction with ACL 2004, 25–26 July 2004, Barcelona, Spain. find
  12. John D. Lafferty, Andrew McCallum, and Fernando C. N. Pereira. 2001. Conditional random fields: Probabilistic models for segmenting and labeling sequence data. In Proceedings of the Eighteenth International Conference on Machine Learning (ICML 2001), Williams College, Williamstown, MA, USA, June 28… find
  13. Wenzhe Pei, Tao Ge, and Baobao Chang. 2014. Max-margin tensor neural network for Chinese word segmentation. In Proceedings of the 52nd Annual Meeting of the Association for Computational Linguistics, ACL 2014, June 22–27, 2014, Baltimore, MD, USA, Volume 1: Long Papers. find
  14. Haonan Li, Zhisong Zhang, Yuqi Ju, and Hai Zhao. 2018. Neural character-level dependency parsing for Chinese. In Proceedings of the Thirty-Second AAAI Conference on Artificial Intelligence, (AAAI-18), the 30th innovative Applications of Artificial Intelligence (IAAI-18), and the 8th AAAI Symposium o… find
  15. Xian Qian and Yang Liu. 2012. Joint Chinese word segmentation, POS tagging and parsing. In Proceedings of the 2012 Joint Conference on Empirical Methods in Natural Language Processing and Computational Natural Language Learning, EMNLP-CoNLL 2012, July 12–14, 2012, Jeju Island, Korea. find
  16. Zhenghua Li, Min Zhang, Wanxiang Che, Ting Liu, Wenliang Chen, and Haizhou Li. 2011. Joint models for Chinese POS tagging and dependency parsing. In Proceedings of the 2011 Conference on Empirical Methods in Natural Language Processing, EMNLP 2011, 27–31 July 2011, John McIntyre Conference Centre, E… find
  17. Xipeng Qiu, Jiayi Zhao, and Xuanjing Huang. 2013. Joint Chinese word segmentation and POS tagging on heterogeneous annotated corpora with multiple task learning. In Proceedings of the 2013 Conference on Empirical Methods in Natural Language Processing, EMNLP 2013, 18–21 October 2013, Grand Hyatt Sea… find
  18. Wang Ling, Chris Dyer, Alan W. Black, and Isabel Trancoso. 2015. Two/too simple adaptations of word2vec for syntax problems. In NAACL HLT 2015, The 2015 Conference of the North American Chapter of the Association for Computational Linguistics: Human Language Technologies, Denver, Colorado, USA, May…
  19. Yan Shao, Christian Hardmeier, Jörg Tiedemann, and Joakim Nivre. 2017. Character-based joint segmentation and POS tagging for Chinese using bidirectional RNN-CRF. In Proceedings of the Eighth International Joint Conference on Natural Language Processing, IJCNLP 2017, Taipei, Taiwan, November 27 - D… find
  20. Ilya Loshchilov and Frank Hutter. 2019. Decoupled weight decay regularization. In 7th International Conference on Learning Representations, ICLR 2019, New Orleans, LA, USA, May 6–9, 2019. find
  21. Tianze Shi, Liang Huang, and Lillian Lee. 2017. Fast(er) exact decoding and global training for transition-based dependency parsing via a minimal feature set. In Proceedings of the 2017 Conference on Empirical Methods in Natural Language Processing, EMNLP 2017, Copenhagen, Denmark, September 9–11, 2… find
  22. Ji Ma, Kuzman Ganchev, and David Weiss. 2018. State-of-the-art Chinese word segmentation with bi-LSTMs. In Proceedings of the 2018 Conference on Empirical Methods in Natural Language Processing, Brussels, Belgium, October 31 -November 4, 2018. find
  23. Yan Song, Shuming Shi, Jing Li, and Haisong Zhang. 2018. Directional skip-gram: Explicitly distinguishing left and right context for word embeddings. In Proceedings of the 2018
  24. Hwee Tou Ng and Jin Kiat Low. 2004. Chinese part-of-speech tagging: One-at-a-time or allat-once? Word-based or character-based? In Meishan Zhang, Yue Zhang, Wanxiang Che, and Ting Liu. 2014. Character-level Chinese dependency parsing. In Proceedings of the 52nd Annual Meeting of the Association for… find
  25. Conference of the North American Chapter of the Association for Computational Linguistics: Human Language Technologies, NAACL-HLT, New Orleans, Louisiana, USA, June 1–6, 2018, Volume 2 (Short Papers). find
  26. Chi Sun, Luyao Huang, and Xipeng Qiu. 2019. Utilizing BERT for aspect-based sentiment analysis via constructing auxiliary sentence. In Proceedings of the 2019 Conference of the North American Chapter of the Association for Computational Linguistics: Human Language Technologies, NAACL-HLT 2019, Minne…
  27. Yue Zhang and Stephen Clark. 2008. Joint word segmentation and POS tagging using a single perceptron. In ACL 2008, Proceedings of the 46th Annual Meeting of the Association for Computational Linguistics, June 15–20, 2008, Columbus, Ohio, USA.
  28. Yue Zhang and Stephen Clark. 2010. A fast decoder for joint word segmentation and pos-tagging using a single discriminative model. In Proceedings of the 2010 Conference on Empirical Methods in Natural Language Processing, EMNLP 2010, 9–11 October 2010, MIT Stata Center, Massachusetts, USA, A meeting… find
  29. Yiou Wang, Jun’ichi Kazama, Yoshimasa Tsuruoka, Wenliang Chen, Yujie Zhang, and Kentaro Torisawa. 2011. Improving Chinese word segmentation and POS tagging with semi-supervised methods using large auto-analyzed data. In Fifth International Joint Conference on Natural Language Processing, IJCNLP 2011… find
  30. Yuan Zhang, Chengtao Li, Regina Barzilay, and Kareem Darwish. 2015. Randomized greedy inference for joint segmentation, POS tagging and dependency parsing. In NAACL HLT 2015, The 2015 Conference of the North American Chapter of the Association for Computational Linguistics: Human Language Technologi… find
  31. Zhiguo Wang, Chengqing Zong, and Nianwen Xue. 2013. A lattice-based framework for joint Chinese word segmentation, POS tagging and parsing. In Proceedings of the 51st Annual Meeting of the Association for Computational Linguistics, ACL 2013, 4–9 August 2013, Sofia, Bulgaria, Volume 2: Short Papers. find
  32. Naiwen Xue, Fei Xia, Fu-Dong Chiou, and Martha Palmer. 2005. The Penn Chinese treebank: Phrase structure annotation of a large corpus. Natural Language Engineering, 11(2):207–238. find
  33. Xiaoqing Zheng, Hanyang Chen, and Tianyu Xu. 2013. Deep learning for Chinese word segmentation and POS tagging. In Proceedings of the 2013 Conference on Empirical Methods in Natural Language Processing, EMNLP 2013, 18–21 October 2013, Grand Hyatt Seattle, Seattle, Washington, USA, A meeting of SIGDA…
  34. Liner Yang, Meishan Zhang, Yang Liu, Maosong Sun, Nan Yu, and Guohong Fu. 2018. Joint POS tagging and dependence parsing with transition-based neural networks. IEEE/ACM Trans. Audio, Speech & Language Processing, 26(8):1352–1358. find
  35. Ming Zhong, Pengfei Liu, Danqing Wang, Xipeng Qiu, and Xuanjing Huang. 2019. Searching for effective neural extractive summarization: What works and what’s next. In Proceedings of the 57th Conference of the Association for Computational Linguistics, ACL 2019, Florence, Italy, July 28 - August 2, 201…
  36. Meishan Zhang, Nan Yu, and Guohong Fu. 2018. A simple and effective neural model for joint word segmentation and POS tagging. IEEE/ACM Trans. Audio, Speech & Language Processing, 26(9). find

Updated

↑ back to top

This page in Markdown → https://md.research.elamur.ai/free/en/papers/yan-2020-graph-based-model-joint-chinese/