Hugging Face Daily Papers · · 3 min read

Reference-Free Post-Training of Open Large Language Models for Multilingual Machine Translation

Mirrored from Hugging Face Daily Papers for archival readability. Support the source by reading on the original site.

Try the live demo: <a href=\"https://huggingface.co/spaces/xiaomi-research/milmmt-46-translation\">https://huggingface.co/spaces/xiaomi-research/milmmt-46-translation</a></p>\n","updatedAt":"2026-08-12T04:28:11.035Z","author":{"_id":"64db17edd68a6ddcc7b3ffd9","avatarUrl":"/avatars/61628600921e4641c1ddd034f3837e9a.svg","fullname":"Pengzhi Gao","name":"gpengzhi","type":"user","isPro":false,"isHf":false,"isHfAdmin":false,"isMod":false,"followerCount":2,"isUserFollowing":false}},"numEdits":1,"identifiedLanguage":{"language":"en","probability":0.907363772392273},"editors":["gpengzhi"],"editorAvatarUrls":["/avatars/61628600921e4641c1ddd034f3837e9a.svg"],"reactions":[],"isReport":false}}],"primaryEmailConfirmed":false,"paper":{"id":"2608.10812","authors":[{"_id":"6a7bdc9d1653ef87c6af1bd6","name":"Chris Han","hidden":false},{"_id":"6a7bdc9d1653ef87c6af1bd7","name":"Pengzhi Gao","hidden":false},{"_id":"6a7bdc9d1653ef87c6af1bd8","name":"Pei Fu","hidden":false},{"_id":"6a7bdc9d1653ef87c6af1bd9","name":"Jian Luan","hidden":false}],"publishedAt":"2026-08-11T00:00:00.000Z","submittedOnDailyAt":"2026-08-12T00:00:00.000Z","title":"Reference-Free Post-Training of Open Large Language Models for Multilingual Machine Translation","submittedOnDailyBy":{"_id":"64db17edd68a6ddcc7b3ffd9","avatarUrl":"/avatars/61628600921e4641c1ddd034f3837e9a.svg","isPro":false,"fullname":"Pengzhi Gao","user":"gpengzhi","type":"user","name":"gpengzhi"},"summary":"We study reference-free post-training for multilingual machine translation with open large language models. Starting from the supervised-finetuned MiLMMT-46-v0.1 models, we apply Group Relative Policy Optimization (GRPO) with a reward that averages two reference-free quality estimation models and is gated by language identification. We then linearly interpolate the supervised fine-tuning (SFT) and reinforcement learning (RL) model checkpoints to obtain MiLMMT-46-v1.0. Across 46 languages, the resulting models consistently improve translation quality over their SFT counterparts, outperform strong recent open baselines, including Seed-X, HY-MT2, and TranslateGemma, and achieve leading reference-free scores against evaluated proprietary systems such as Google Translate, Gemini 3 Pro, and GPT-5. We further investigate on-policy distillation and find that it reaches, but does not surpass, the quality frontier achieved by RL with checkpoint interpolation. We release the models and code to facilitate future research.","upvotes":5,"discussionId":"6a7bdc9d1653ef87c6af1bda","githubRepo":"https://github.com/xiaomi-research/gemmax","githubRepoAddedBy":"user","ai_summary":"Open multilingual translation models are improved via group relative policy optimization with reference-free quality rewards and checkpoint interpolation, surpassing strong open and proprietary baselines.","ai_keywords":["Group Relative Policy Optimization","quality estimation","language identification","supervised fine-tuning","reinforcement learning","checkpoint interpolation","on-policy distillation","multilingual machine translation"],"ai_summary_model":"thinkingmachines/Inkling-Small","githubStars":68,"organization":{"_id":"6821ba7e5a7efab94a235406","name":"xiaomi-research","fullname":"Xiaomi Research","avatar":"https://cdn-avatars.huggingface.co/v1/production/uploads/673735e4373ad40af7f81ea1/DR4m0bz2Du1l0Z8Txg351.png"}},"canReadDatabase":false,"canManagePapers":false,"canSubmit":false,"hasHfLevelAccess":false,"upvoted":false,"upvoters":[{"_id":"64db17edd68a6ddcc7b3ffd9","avatarUrl":"/avatars/61628600921e4641c1ddd034f3837e9a.svg","isPro":false,"fullname":"Pengzhi Gao","user":"gpengzhi","type":"user"},{"_id":"69bcb85876fe7a5ea0a52581","avatarUrl":"https://cdn-avatars.huggingface.co/v1/production/uploads/noauth/NMYcwRgtzWxIzkoaAgSOh.jpeg","isPro":false,"fullname":"井上 美月","user":"jrobinson9","type":"user"},{"_id":"6a5db0ce059560f3ce0455d7","avatarUrl":"/avatars/71f29595ada24ae57c0d8b2004a2ebf2.svg","isPro":false,"fullname":"Cathy Payne","user":"cathypayne9","type":"user"},{"_id":"6694e62da0a0fcbfa89f5077","avatarUrl":"/avatars/87004096308a290f4c7f7a55086120fc.svg","isPro":false,"fullname":"HAN","user":"HAN1111111","type":"user"},{"_id":"661ab1f1fa3b144a381fa454","avatarUrl":"https://cdn-avatars.huggingface.co/v1/production/uploads/661ab1f1fa3b144a381fa454/IlpZBb9NCjo7ntFwMIH53.png","isPro":false,"fullname":"Urro","user":"urroxyz","type":"user"}],"acceptLanguages":["en"],"dailyPaperRank":0,"organization":{"_id":"6821ba7e5a7efab94a235406","name":"xiaomi-research","fullname":"Xiaomi Research","avatar":"https://cdn-avatars.huggingface.co/v1/production/uploads/673735e4373ad40af7f81ea1/DR4m0bz2Du1l0Z8Txg351.png"},"markdownContentUrl":"https://huggingface.co/buckets/huggingchat/papers-content/resolve/2608/2608.10812.md","query":{}}">
Papers
arxiv:2608.10812

Reference-Free Post-Training of Open Large Language Models for Multilingual Machine Translation

Published on Aug 11
· Submitted by
Pengzhi Gao
on Aug 12
Authors:
,

Abstract

Open multilingual translation models are improved via group relative policy optimization with reference-free quality rewards and checkpoint interpolation, surpassing strong open and proprietary baselines.

We study reference-free post-training for multilingual machine translation with open large language models. Starting from the supervised-finetuned MiLMMT-46-v0.1 models, we apply Group Relative Policy Optimization (GRPO) with a reward that averages two reference-free quality estimation models and is gated by language identification. We then linearly interpolate the supervised fine-tuning (SFT) and reinforcement learning (RL) model checkpoints to obtain MiLMMT-46-v1.0. Across 46 languages, the resulting models consistently improve translation quality over their SFT counterparts, outperform strong recent open baselines, including Seed-X, HY-MT2, and TranslateGemma, and achieve leading reference-free scores against evaluated proprietary systems such as Google Translate, Gemini 3 Pro, and GPT-5. We further investigate on-policy distillation and find that it reaches, but does not surpass, the quality frontier achieved by RL with checkpoint interpolation. We release the models and code to facilitate future research.

Community

Upload images, audio, and videos by dragging in the text input, pasting, or clicking here.
Tap or paste here to upload images

· Sign up or log in to comment

Get this paper in your agent:

hf papers read 2608.10812
Don't have the latest CLI?
curl -LsSf https://hf.co/cli/install.sh | bash

Models citing this paper

Datasets citing this paper

No dataset linking this paper

Cite arxiv.org/abs/2608.10812 in a dataset README.md to link it from this page.

Spaces citing this paper

Collections including this paper

Discussion (0)

Sign in to join the discussion. Free account, 30 seconds — email code or GitHub.

Sign in →

No comments yet. Sign in and be the first to say something.

More from Hugging Face Daily Papers