Title
Modeling Coverage for Non-Autoregressive Neural Machine Translation
Abstract
Non-Autoregressive Neural Machine Translation (NAT) has achieved significant inference speedup by generating all tokens simultaneously. Despite its high efficiency, NAT usually suffers from two kinds of translation errors: over-translation (e.g. repeated tokens) and under-translation (e.g. missing translations), which eventually limits the translation quality. In this paper, we argue that these issues of NAT can be addressed through coverage modeling, which has been proved to be useful in autoregressive decoding. We propose a novel Coverage-NAT to model the coverage information directly by a token-level coverage iterative refinement mechanism and a sentence-level coverage agreement, which can remind the model if a source token has been translated or not and improve the semantics consistency between the translation and the source, respectively. Experimental results on WMT14 En <-> De and WMT16 En <-> Ro translation tasks show that our method can alleviate those errors and achieve strong improvements over the baseline system.
Year
DOI
Venue
2021
10.1109/IJCNN52387.2021.9533529
2021 INTERNATIONAL JOINT CONFERENCE ON NEURAL NETWORKS (IJCNN)
DocType
ISSN
Citations 
Conference
2161-4393
0
PageRank 
References 
Authors
0.34
0
3
Name
Order
Citations
PageRank
Yong Shan100.68
Yang Feng230138.39
Chenze Shao302.70