# The Pareto Frontier of Instance-Dependent Guarantees in Multi-Player Multi-Armed Bandits with no Communication

arXiv: https://arxiv.org/abs/2202.09653 · HTML: https://mlsanity.com/paper/2202.09653/

## Key facts

- Cited by 2 papers in the map (data through 14 Oct 2026).
- Builds on 11 of its 17 references that are in the map.
- First posted on arXiv 19 Feb 2022.

## Builds on (most cited first, 11 of 11)

- [SIC-MMAB: Synchronisation Involves Communication in Multiplayer Multi-Armed Bandits](https://mlsanity.com/paper/1809.08151/) (2018)
- [Decentralized Multi-player Multi-armed Bandits with No Collision Information](https://mlsanity.com/paper/2003.00162/) (2020)
- [Concurrent bandits and cognitive radio networks](https://mlsanity.com/paper/1404.5421/) (2014)
- [Multiplayer bandits without observing collision information](https://mlsanity.com/paper/1808.08416/) (2018)
- [Multi-Armed Bandit Learning in IoT Networks: Learning helps even in non-stationary settings](https://mlsanity.com/paper/1807.00491/) (2018)
- [Non-Stochastic Multi-Player Multi-Armed Bandits: Optimal Rate With Collision Information, Sublinear Without](https://mlsanity.com/paper/1904.12233/) (2019)
- [Cooperative and Stochastic Multi-Player Multi-Armed Bandit: Optimal Regret With Neither Communication Nor Collisions](https://mlsanity.com/paper/2011.03896/) (2020)
- [Multi-Player Bandits: The Adversarial Case](https://mlsanity.com/paper/1902.08036/) (2019)
- [Coordination without communication: optimal regret in two players multi-armed bandits](https://mlsanity.com/paper/2002.07596/) (2020)
- [Towards Optimal Algorithms for Multi-Player Bandits without Collision Sensing Information](https://mlsanity.com/paper/2103.13059/) (2021)
- [An Instance-Dependent Analysis for the Cooperative Multi-Player Multi-Armed Bandit](https://mlsanity.com/paper/2111.04873/) (2021)

## Built on by (most cited first, 2 of 2)

- [Meet Me at the Arm: The Cooperative Multi-Armed Bandits Problem with Shareable Arms](https://mlsanity.com/paper/2506.10127/) (2025)
- [Exact Regret Frontiers and Externality Scheduling in Centralized Serial-Dictatorship Bandits](https://mlsanity.com/paper/2609.19963/) (2026)

## Abstract (arXiv)

We study the stochastic multi-player multi-armed bandit problem. In this problem, m players cooperate to maximize their total reward from K > m arms. However the players cannot communicate and are penalized (e.g. receive no reward) if they pull the same arm at the same time. We ask whether it is possible to obtain optimal instance-dependent regret tildeO(1/Delta) where Delta is the gap between the m-th and m+1-st best arms. Such guarantees were recently achieved in a model allowing the players to implicitly communicate through intentional collisions. Surprisingly, we show that with no communication at all, such guarantees are not achievable. In fact, obtaining the optimal tildeO(1/Delta) regret for some values of Delta necessarily implies strictly sub-optimal regret in other regimes. Our main result is a complete characterization of the Pareto optimal instance-dependent trade-offs that are possible with no communication. Our algorithm generalizes that of Bubeck, Budzinski, and the second author. As there, our algorithm succeeds even when feedback upon collision can be corrupted by an adaptive adversary, thanks to a strong no-collision property. Our lower bound is based on topological obstructions at multiple scales and is completely new.
