Joint Chinese Word Segmentation and Part-of-speech Tagging via Multi-channel Attention of Character N-grams

Yuanhe Tian, Yan Song, Fei Xia


Abstract
Chinese word segmentation (CWS) and part-of-speech (POS) tagging are two fundamental tasks for Chinese language processing. Previous studies have demonstrated that jointly performing them can be an effective one-step solution to both tasks and this joint task can benefit from a good modeling of contextual features such as n-grams. However, their work on modeling such contextual features is limited to concatenating the features or their embeddings directly with the input embeddings without distinguishing whether the contextual features are important for the joint task in the specific context. Therefore, their models for the joint task could be misled by unimportant contextual information. In this paper, we propose a character-based neural model for the joint task enhanced by multi-channel attention of n-grams. In the attention module, n-gram features are categorized into different groups according to several criteria, and n-grams in each group are weighted and distinguished according to their importance for the joint task in the specific context. To categorize n-grams, we try two criteria in this study, i.e., n-gram frequency and length, so that n-grams having different capabilities of carrying contextual information are discriminatively learned by our proposed attention module. Experimental results on five benchmark datasets for CWS and POS tagging demonstrate that our approach outperforms strong baseline models and achieves state-of-the-art performance on all five datasets.
Anthology ID:
2020.coling-main.187
Volume:
Proceedings of the 28th International Conference on Computational Linguistics
Month:
December
Year:
2020
Address:
Barcelona, Spain (Online)
Editors:
Donia Scott, Nuria Bel, Chengqing Zong
Venue:
COLING
SIG:
Publisher:
International Committee on Computational Linguistics
Note:
Pages:
2073–2084
Language:
URL:
https://aclanthology.org/2020.coling-main.187
DOI:
10.18653/v1/2020.coling-main.187
Bibkey:
Cite (ACL):
Yuanhe Tian, Yan Song, and Fei Xia. 2020. Joint Chinese Word Segmentation and Part-of-speech Tagging via Multi-channel Attention of Character N-grams. In Proceedings of the 28th International Conference on Computational Linguistics, pages 2073–2084, Barcelona, Spain (Online). International Committee on Computational Linguistics.
Cite (Informal):
Joint Chinese Word Segmentation and Part-of-speech Tagging via Multi-channel Attention of Character N-grams (Tian et al., COLING 2020)
Copy Citation:
PDF:
https://aclanthology.org/2020.coling-main.187.pdf
Code
 cuhksz-nlp/mcasp
Data
Universal Dependencies