Multiscale Collaborative Deep Models for Neural Machine Translation

Xiangpeng Wei, Heng Yu, Yue Hu, Yue Zhang, Rongxiang Weng, Weihua Luo


Abstract
Recent evidence reveals that Neural Machine Translation (NMT) models with deeper neural networks can be more effective but are difficult to train. In this paper, we present a MultiScale Collaborative (MSC) framework to ease the training of NMT models that are substantially deeper than those used previously. We explicitly boost the gradient back-propagation from top to bottom levels by introducing a block-scale collaboration mechanism into deep NMT models. Then, instead of forcing the whole encoder stack directly learns a desired representation, we let each encoder block learns a fine-grained representation and enhance it by encoding spatial dependencies using a context-scale collaboration. We provide empirical evidence showing that the MSC nets are easy to optimize and can obtain improvements of translation quality from considerably increased depth. On IWSLT translation tasks with three translation directions, our extremely deep models (with 72-layer encoders) surpass strong baselines by +2.2~+3.1 BLEU points. In addition, our deep MSC achieves a BLEU score of 30.56 on WMT14 English-to-German task that significantly outperforms state-of-the-art deep NMT models. We have included the source code in supplementary materials.
Anthology ID:
2020.acl-main.40
Volume:
Proceedings of the 58th Annual Meeting of the Association for Computational Linguistics
Month:
July
Year:
2020
Address:
Online
Venue:
ACL
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
414–426
Language:
URL:
https://aclanthology.org/2020.acl-main.40
DOI:
10.18653/v1/2020.acl-main.40
Bibkey:
Cite (ACL):
Xiangpeng Wei, Heng Yu, Yue Hu, Yue Zhang, Rongxiang Weng, and Weihua Luo. 2020. Multiscale Collaborative Deep Models for Neural Machine Translation. In Proceedings of the 58th Annual Meeting of the Association for Computational Linguistics, pages 414–426, Online. Association for Computational Linguistics.
Cite (Informal):
Multiscale Collaborative Deep Models for Neural Machine Translation (Wei et al., ACL 2020)
Copy Citation:
PDF:
https://aclanthology.org/2020.acl-main.40.pdf
Video:
 http://slideslive.com/38928953
Code
 pemywei/MSC-NMT