# Kernel-based methods for bandit convex optimization

arXiv: https://arxiv.org/abs/1607.03084 · HTML: https://mlsanity.com/paper/1607.03084/

## Key facts

- Cited by 63 papers in the map (data through 14 Oct 2026).
- First posted on arXiv 11 Jul 2016.

## Built on by (most cited first, 30 of 63)

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- [On Adaptivity in Non-stationary Stochastic Optimization With Bandit Feedback](https://mlsanity.com/paper/2210.05584/) (2022)
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- [Minimax Regret for Bandit Convex Optimisation of Ridge Functions](https://mlsanity.com/paper/2106.00444/) (2021)

## Abstract (arXiv)

We consider the adversarial convex bandit problem and we build the first poly(T)-time algorithm with poly(n) √T-regret for this problem. To do so we introduce three new ideas in the derivative-free optimization literature: (i) kernel methods, (ii) a generalization of Bernoulli convolutions, and (iii) a new annealing schedule for exponential weights (with increasing learning rate). The basic version of our algorithm achieves tildeO(n9.5 √T)-regret, and we show that a simple variant of this algorithm can be run in poly(n log(T))-time per step at the cost of an additional poly(n) To(1) factor in the regret. These results improve upon the tildeO(n11 √T)-regret and exp(poly(T))-time result of the first two authors, and the log(T)poly(n) √T-regret and log(T)poly(n)-time result of Hazan and Li. Furthermore we conjecture that another variant of the algorithm could achieve tildeO(n1.5 √T)-regret, and moreover that this regret is unimprovable (the current best lower bound being Omega(n √T) and it is achieved with linear functions). For the simpler situation of zeroth order stochastic convex optimization this corresponds to the conjecture that the optimal query complexity is of order n3 / ε2.
