Online Language Adaptive Sampling for Better Distributed Cross-lingual Gains

Quang Phuoc Nguyen, Félix Gaschi, David Anugraha, Santiago Martínez Novoa, En-Shiun Annie Lee


Abstract
Realignment is a promising approach for improving the cross-lingual transfer ability of multilingual language models, particularly for extremely low-resource languages (LRLs). However, existing realignment methods rely on uniform and random sampling of parallel sentences across languages, which may be suboptimal under limited batch sizes. In practice, models may benefit from seeing certain languages more frequently, especially those that are poorly aligned, and the optimal distribution can evolve throughout training. In this work, we propose a simple yet effective adaptive sampling strategy that assigns trainable sampling probabilities to each language. Languages that contribute more to the realignment loss are sampled more frequently in subsequent batches, and the optimal distribution can evolve throughout training. Our method employs an inner–outer optimization loop with a small overhead, leading to consistent performance improvements and, more importantly, distributing the gains across languages. We observed a +0.67 average performance increase on all tasks with XLM-R, and +0.60 with Gemma 2 9B compared with uniform realignment. Furthermore, our method is robust across different models.
Anthology ID:
2026.findings-emnlp.1724
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:
36873–36891
Language:
URL:
https://aclanthology.org/2026.findings-emnlp.1724/
DOI:
10.18653/2026.findings-emnlp.1724
Bibkey:
Cite (ACL):
Quang Phuoc Nguyen, Félix Gaschi, David Anugraha, Santiago Martínez Novoa, and En-Shiun Annie Lee. 2026. Online Language Adaptive Sampling for Better Distributed Cross-lingual Gains. In Findings of the Association for Computational Linguistics: EMNLP 2026, pages 36873–36891, Budapest, Hungary. Association for Computational Linguistics.
Cite (Informal):
Online Language Adaptive Sampling for Better Distributed Cross-lingual Gains (Nguyen et al., Findings 2026)
Copy Citation:
PDF:
https://aclanthology.org/2026.findings-emnlp.1724.pdf