🤖 AI Summary
This work addresses the challenge of heavy-tailed noise severely degrading accuracy and stability in distributed parameter estimation within densely deployed systems such as the Internet of Things. The authors propose a robust distributed estimation algorithm grounded in a nonlinear consensus+innovations framework, incorporating general nonlinear functions in both consensus and innovation updates to mitigate the adverse effects of heavy-tailed noise. For the first time under heavy-tailed noise conditions, the paper establishes theoretical guarantees of almost sure convergence and asymptotic normality for the proposed algorithm, revealing a quantitative trade-off between noise decay rates and network connectivity. The method achieves both estimation consistency and asymptotic optimality, thereby providing a novel theoretical foundation for highly robust distributed learning.
📝 Abstract
We present an algorithm for distributed estimation of an unknown vector parameter $\boldsymbolθ^\ast \in {\mathbb R}^M$ in the presence of heavy-tailed observation and communication noises. Heavy-tailed noises frequently appear, e.g., in densely deployed Internet of Things (IoT) or wireless sensor network systems. The presented algorithm falls within the class of \emph{consensus+innovation} estimators and combats the effect of the heavy-tailed noises by adding general nonlinearities in the consensus and innovations update parts. We present results on almost sure convergence and asymptotic normality of the estimator. In addition, we provide novel analytical studies that reveal interesting tradeoffs between the system noises and the underlying network topology.