@inproceedings{xiong-etal-2025-hs,
    title = "{HS}-{ST}a{R}: Hierarchical Sampling for Self-Taught Reasoners via Difficulty Estimation and Budget Reallocation",
    author = "Xiong, Feng  and
      Xu, Hongling  and
      Wang, Yifei  and
      Cheng, Runxi  and
      Wang, Yong  and
      Chu, Xiangxiang",
    editor = "Christodoulopoulos, Christos  and
      Chakraborty, Tanmoy  and
      Rose, Carolyn  and
      Peng, Violet",
    booktitle = "Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing",
    month = nov,
    year = "2025",
    address = "Suzhou, China",
    publisher = "Association for Computational Linguistics",
    url = "https://aclanthology.org/2025.emnlp-main.282/",
    pages = "5539--5555",
    ISBN = "979-8-89176-332-6"
}