# Sparse Stochastic Bandits

arXiv: https://arxiv.org/abs/1706.01383 · HTML: https://mlsanity.com/paper/1706.01383/

## Key facts

- Cited by 8 papers in the map (data through 14 Oct 2026).
- First posted on arXiv 5 Jun 2017.

## Built on by (most cited first, 8 of 8)

- [Stability-penalty-adaptive follow-the-regularized-leader: Sparsity, game-dependency, and best-of-both-worlds](https://mlsanity.com/paper/2305.17301/) (2023)
- [Non-stationary Bandits and Meta-Learning with a Small Set of Optimal Arms](https://mlsanity.com/paper/2202.13001/) (2022)
- [Multi-Armed Bandits with Network Interference](https://mlsanity.com/paper/2405.18621/) (2024)
- [Uplifting Bandits](https://mlsanity.com/paper/2206.04091/) (2022)
- [Stochastic Shortest Path with Sparse Adversarial Costs](https://mlsanity.com/paper/2511.00637/) (2025)
- [Covariance-adapting algorithm for semi-bandits with application to sparse rewards](https://mlsanity.com/paper/2604.13738/) (2026)
- [Adversarial Online Collaborative Filtering](https://mlsanity.com/paper/2302.05765/) (2023)
- [Stochastic Linear Bandits with Partially Observed Actions](https://mlsanity.com/paper/2607.08971/) (2026)

## Abstract (arXiv)

In the classical multi-armed bandit problem, d arms are available to the decision maker who pulls them sequentially in order to maximize his cumulative reward. Guarantees can be obtained on a relative quantity called regret, which scales linearly with d (or with sqrt(d) in the minimax sense). We here consider the sparse case of this classical problem in the sense that only a small number of arms, namely s < d, have a positive expected reward. We are able to leverage this additional assumption to provide an algorithm whose regret scales with s instead of d. Moreover, we prove that this algorithm is optimal by providing a matching lower bound - at least for a wide and pertinent range of parameters that we determine - and by evaluating its performance on simulated data.
