@InProceedings{su-liu-fang:2026:wmt,
  author    = {Su, Meng  and  Liu, Jian  and  Fang, Youxuan},
  title     = {Jiutian-MT-8B at WMT26: Faithfulness-First Training for Chinese-Southeast Asian Translation},
  booktitle      = {Proceedings of the Eleventh Conference on Machine Translation},
  month          = {October},
  year           = {2026},
  address        = {Budapest, Hungary},
  publisher      = {Association for Computational Linguistics},
  pages     = {2373--2377},
  abstract  = {This paper describes Jiutian-MT-8B, our submission to the WMT 2026 Chinese-Southeast Asian Multilingual Machine Translation shared task. The system adapts the 8-billion-parameter Jiutian-8B-Instruct checkpoint to fourteen translation directions between Chinese and Thai, Vietnamese, Lao, Burmese, Khmer, Indonesian, and Malay. We formulate translation as a tightly controlled instruction-following task and use a four-stage full-parameter training recipe: (i) supervised multilingual adaptation on released parallel data, (ii) faithfulness first confidence-gated multi-pair preference alignment (F2MTA), (iii) direction-coupled, evidence-filtered self-training from task monolingual data, and (iv) a final clean-data calibration stage. The preference stage uses a partial order: a candidate must gain source adequacy without materially sacrificing target fluency, rather than merely win a scalarized quality score. The recipe directly updates all Jiutian-8B parameters with sharded bf16 training while retaining authentic data anchors to limit synthetic-data drift. The official test set is blind at the time of writing; numerical main results are therefore deliberately unreported. We nevertheless specify the data scope, translation interface, training protocol, and evaluation plan needed to complete the report once official scores are returned.},
  url       = {https://aclanthology.org/2026.wmt-1.180}
}