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Differentially Private Multi-Armed Bandits in the Shuffle Model

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 نشر من قبل Jay Tenenbaum
 تاريخ النشر 2021
  مجال البحث الهندسة المعلوماتية
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We give an $(varepsilon,delta)$-differentially private algorithm for the multi-armed bandit (MAB) problem in the shuffle model with a distribution-dependent regret of $Oleft(left(sum_{ain [k]:Delta_a>0}frac{log T}{Delta_a}right)+frac{ksqrt{logfrac{1}{delta}}log T}{varepsilon}right)$, and a distribution-independent regret of $Oleft(sqrt{kTlog T}+frac{ksqrt{logfrac{1}{delta}}log T}{varepsilon}right)$, where $T$ is the number of rounds, $Delta_a$ is the suboptimality gap of the arm $a$, and $k$ is the total number of arms. Our upper bound almost matches the regret of the best known algorithms for the centralized model, and significantly outperforms the best known algorithm in the local model.



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