@article{optimalheterogeneouscollaborativelinear,
  title = {Optimal Multitask Linear Regression and Contextual Bandits under Sparse Heterogeneity},
  author = {Xinmeng Huang and Kan Xu and Donghwan Lee and Hamed Hassani and Hamsa Bastani and Edgar Dobriban},
  year = {2023},
  eprint = {2306.06291},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2306.06291v3},
}