Sharper Regret Bounds for Time-Varying Gaussian Process Bandits with Constant Exploration
- URL: http://arxiv.org/abs/2608.18863v1
- Date: Wed, 19 Aug 2026 12:36:05 GMT
- Title: Sharper Regret Bounds for Time-Varying Gaussian Process Bandits with Constant Exploration
- Abstract summary: GP-UCB can be run with a constant exploration parameter and obtain an expected-regret bound whose coefficient depends on the drift rate.<n>For the squared exponential kernel, it yields $tilde_T/T=widetildemathcal O(1/2)$ and expected average regret $widetildemathcal O(1/4)$ in the persistent-drift regime.
- Score: 0.0
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: We study Bayesian optimization in a time-varying environment where the unknown reward function evolves according to a Gaussian process drift model. Existing GP-UCB analyses in this setting typically require the exploration parameter to grow with the horizon to maintain uniform confidence bounds. Using per-round local confidence events, we show that GP-UCB can instead be run with a constant exploration parameter and obtain an expected-regret bound whose coefficient depends on the drift rate. We also derive a sharper time-varying maximum-information-gain bound. For the squared exponential kernel, it yields $\tildeγ_T/T=\widetilde{\mathcal O}(ε^{1/2})$ and expected average regret $\widetilde{\mathcal O}(ε^{1/4})$ in the persistent-drift regime. The same constant-exploration analysis also yields realized-regret guarantees. Simulations support the predicted logarithmic dependence of the bound-suggested exploration parameter on $1/ε$.
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