@article{dadpocostefficientdifficultyawareprefere,
  title = {DA-DPO: Cost-efficient Difficulty-aware Preference Optimization for Reducing MLLM Hallucinations},
  author = {Longtian Qiu and Shan Ning and Chuyu Zhang and Jiaxuan Sun and Xuming He},
  year = {2026},
  eprint = {2601.00623},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2601.00623},
}