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Title: Linear Stochastic Bandits over a Bit-Constrained Channel
One of the primary challenges in large-scale distributed learning stems from stringent communication constraints. While several recent works address this challenge for static optimization problems, sequential decision-making under uncertainty has remained much less explored in this regard. Motivated by this gap, we introduce a new linear stochastic bandit formulation over a bit-constrained channel. Specifically, in our setup, an agent interacting with an environment transmits encoded estimates of an unknown model parameter to a server over a communication channel of finite capacity. The goal of the server is to take actions based on these estimates to minimize cumulative regret. To this end, we develop a novel and general algorithmic framework that hinges on two main components: (i) an adaptive encoding mechanism that exploits statistical concentration bounds, and (ii) a decision-making principle based on confidence sets that account for encoding errors. As our main result, we prove that when the unknown model is d-dimensional, a channel capacity of O(d) bits suffices to achieve order-optimal regret. We also establish that for the simpler unstructured multi-armed bandit problem, 1 bit channel capacity is sufficient for achieving optimal regret bounds.  more » « less
Award ID(s):
1910056
NSF-PAR ID:
10490382
Author(s) / Creator(s):
; ;
Publisher / Repository:
Proceedings of Machine Learning Research
Date Published:
Journal Name:
Learning for Dynamics and Control
Format(s):
Medium: X
Location:
Philadelphia
Sponsoring Org:
National Science Foundation
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