Sampling to Achieve the Goal: An Age-aware Remote Markov Decision Process
Aimin Li, Shaohua Wu, Gary C. F. Lee, Xiaomeng Cheng, Sumei Sun
TL;DR
The paper addresses the link between AoI and remote decision quality in a time-slotted remote MDP where observation delay is controllable via AoI, not fixed. It introduces an age-aware remote MDP that can be reduced to a standard, delay-free MDP with a constraint, enabling tractable optimization of joint sampling and control actions. The authors prove the existence of optimal stationary deterministic policies under unichain conditions and propose two practical solvers (Bisec-MRVI and FPBI) with FPBI offering faster convergence. A key finding is that minimizing AoI alone can yield suboptimal decision performance, illustrating the value of goal-oriented sampling that directly optimizes the remote decision-making objective; AoI thus functions effectively as side information to facilitate decisions.
Abstract
Age of Information (AoI) has been recognized as an important metric to measure the freshness of information. Central to this consensus is that minimizing AoI can enhance the freshness of information, thereby facilitating the accuracy of subsequent decision-making processes. However, to date the direct causal relationship that links AoI to the utility of the decision-making process is unexplored. To fill this gap, this paper provides a sampling-control co-design problem, referred to as an age-aware remote Markov Decision Process (MDP) problem, to explore this unexplored relationship. Our framework revisits the sampling problem in [1] with a refined focus: moving from AoI penalty minimization to directly optimizing goal-oriented remote decision-making process under random delay. We derive that the age-aware remote MDP problem can be reduced to a standard MDP problem without delays, and reveal that treating AoI solely as a metric for optimization is not optimal in achieving remote decision making. Instead, AoI can serve as important side information to facilitate remote decision making.
