@article{demystifyinggrouprelativepolicyoptimizat,
  title = {Demystifying Group Relative Policy Optimization: Its Policy Gradient is a U-Statistic},
  author = {Hongyi Zhou and Kai Ye and Erhan Xu and Jin Zhu and Ying Yang and Shijin Gong and Chengchun Shi},
  year = {2026},
  eprint = {2603.01162},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2603.01162},
}