Enhancing Accuracy in Differentially Private Distributed Optimization Through Sensitivity Reduction

In this paper, we investigate the problem of differentially private distributed optimization. Recognizing that lower sensitivity leads to higher accuracy, we analyze the key factors influencing the sensitivity of differentially private distributed algorithms. Building on these insights, we propose a novel differentially private distributed algorithm that enhances optimization accuracy by reducing sensitivity. To ensure practical applicability, we derive a closed-form expression for the noise parameter as a function of the privacy budget. Furthermore, we rigorously prove that the proposed algorithm can achieve arbitrarily rigorous $\epsilon$-differential privacy, establish its convergence in the mean square sense, and provide an upper bound on its optimization accuracy. Finally, extensive comparisons with various privacy-preserving methods validate the effectiveness of our algorithm.