@inproceedings{luo-etal-2025-semi,
    title = "Semi-supervised Fine-tuning for Large Language Models",
    author = "Luo, Junyu  and
      Luo, Xiao  and
      Chen, Xiusi  and
      Xiao, Zhiping  and
      Ju, Wei  and
      Zhang, Ming",
    editor = "Chiruzzo, Luis  and
      Ritter, Alan  and
      Wang, Lu",
    booktitle = "Findings of the Association for Computational Linguistics: NAACL 2025",
    month = apr,
    year = "2025",
    address = "Albuquerque, New Mexico",
    publisher = "Association for Computational Linguistics",
    url = "https://preview.aclanthology.org/fix-sig-urls/2025.findings-naacl.151/",
    pages = "2795--2808",
    ISBN = "979-8-89176-195-7",
    abstract = "Supervised fine-tuning (SFT) is crucial in adapting large language models (LLMs) to a specific domain or task. However, only a limited amount of labeled data is available in practical applications, which poses a severe challenge for SFT in yielding satisfactory results. Therefore, a data-efficient framework that can fully exploit labeled and unlabeled data for LLM fine-tuning is highly anticipated.Towards this end, we introduce a **semi-supervised fine-tuning (SemiFT)** task and a framework named **SemiEvol** for LLM alignment from a propagate-and-select manner. For knowledge propagation, SemiEvol adopts a bi-level approach, propagating knowledge from labeled data to unlabeled data through both in-weight and in-context methods. For knowledge selection, SemiEvol incorporates a collaborative learning mechanism, selecting higher-quality pseudo-response samples. We conducted experiments using GPT-4o-mini and Llama-3.1 on seven general or domain-specific datasets, demonstrating significant improvements in model performance on target data. Furthermore, we compared SemiEvol with SFT and self-evolution methods, highlighting its practicality in hybrid data scenarios. Github Repository: [https://github.com/luo-junyu/SemiEvol](https://github.com/luo-junyu/SemiEvol)."
}