EDWARD-NMT: Elastic Dimensions With Adaptive Routing and Dual-consistency for Neural Machine Translation

Edward Nguyen, Thai Tran, Kiet Anh Hoang, Duy Hoang, Duy Vo, Khanh Le, Vu Le


Abstract
Sparse Mixture-of-Experts (MoE) is a powerful paradigm for scaling Neural Machine Translation (NMT) and managing language heterogeneity. However, practical limitations hinder its deployment on resource-constrained devices: the entire expert pool must remain in memory, and the per-token compute budget is statically fixed during training by rigid top-k routing. We introduce EDWARD-NMT (Elastic Dimensions With Adaptive Routing and Dual-consistency for NMT), a novel MoE encoder-decoder architecture designed for a “train once, deploy anywhere” paradigm that exposes a family of deployable sub-networks at inference time. EDWARD-NMT integrates three key innovations: (i) Matryoshka-style elastic dimensions to flexibly reduce the memory footprint; (ii) an adaptive sigmoid router with a learned, task-conditioned threshold, allowing each token to dynamically determine its active expert count; and (iii) a dual-consistency objective to maximize the performance of the extracted sub-networks. Extensive experiments on PhoMT (En↔Vi), WMT-14 (En↔De), multilingual OPUS-16, and a multi-domain De↔En benchmark validate our approach. The full-capacity architecture matches or exceeds strong MoE baselines with improved parameter efficiency. Furthermore, the sub-networks seamlessly extracted from a single checkpoint consistently outperform comparably sized dense Transformers without any retraining.
Anthology ID:
2026.findings-emnlp.1763
Volume:
Findings of the Association for Computational Linguistics: EMNLP 2026
Month:
October
Year:
2026
Address:
Budapest, Hungary
Editors:
Hung-Yi Lee, Sunipa Dev, Jessy Li, Desmond Elliott
Venue:
Findings
SIG:
SIGDAT
Publisher:
Association for Computational Linguistics
Note:
Pages:
37707–37727
Language:
URL:
https://aclanthology.org/2026.findings-emnlp.1763/
DOI:
10.18653/2026.findings-emnlp.1763
Bibkey:
Cite (ACL):
Edward Nguyen, Thai Tran, Kiet Anh Hoang, Duy Hoang, Duy Vo, Khanh Le, and Vu Le. 2026. EDWARD-NMT: Elastic Dimensions With Adaptive Routing and Dual-consistency for Neural Machine Translation. In Findings of the Association for Computational Linguistics: EMNLP 2026, pages 37707–37727, Budapest, Hungary. Association for Computational Linguistics.
Cite (Informal):
EDWARD-NMT: Elastic Dimensions With Adaptive Routing and Dual-consistency for Neural Machine Translation (Nguyen et al., Findings 2026)
Copy Citation:
PDF:
https://aclanthology.org/2026.findings-emnlp.1763.pdf