Adaptation to the Range in $K$-Armed Bandits
- URL: http://arxiv.org/abs/2006.03378v3
- Date: Wed, 15 Jun 2022 10:34:03 GMT
- Title: Adaptation to the Range in $K$-Armed Bandits
- Abstract summary: We consider bandit problems with $K$ arms associated with a bounded distribution supported on the range $[m,M]$.
A new trade-off between distribution-dependent and distribution-free regret bounds arises, which prevents from simultaneously achieving the typical $ln T$ and $sqrtT$ bounds.
- Score: 1.14219428942199
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: We consider stochastic bandit problems with $K$ arms, each associated with a
bounded distribution supported on the range $[m,M]$. We do not assume that the
range $[m,M]$ is known and show that there is a cost for learning this range.
Indeed, a new trade-off between distribution-dependent and distribution-free
regret bounds arises, which prevents from simultaneously achieving the typical
$\ln T$ and $\sqrt{T}$ bounds. For instance, a $\sqrt{T}$}distribution-free
regret bound may only be achieved if the distribution-dependent regret bounds
are at least of order $\sqrt{T}$. We exhibit a strategy achieving the rates for
regret indicated by the new trade-off.
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