Stochastic Mirror Descent for Convex Optimization with Consensus Constraints

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Borovykh, Anastasia, Kantas, Nikolas, Parpas, Panos, Pavliotis, Grigorios A.
Natura: Preprint
Pubblicazione: 2022
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866911793017782272
author Borovykh, Anastasia
Kantas, Nikolas
Parpas, Panos
Pavliotis, Grigorios A.
author_facet Borovykh, Anastasia
Kantas, Nikolas
Parpas, Panos
Pavliotis, Grigorios A.
contents The mirror descent algorithm is known to be effective in situations where it is beneficial to adapt the mirror map to the underlying geometry of the optimization model. However, the effect of mirror maps on the geometry of distributed optimization problems has not been previously addressed. In this paper we study an exact distributed mirror descent algorithm in continuous-time under additive noise. We establish a linear convergence rate of the proposed dynamics for the setting of convex optimization. Our analysis draws motivation from the Augmented Lagrangian and its relation to gradient tracking. To further explore the benefits of mirror maps in a distributed setting we present a preconditioned variant of our algorithm with an additional mirror map over the Lagrangian dual variables. This allows our method to adapt to both the geometry of the primal variables, as well as to the geometry of the consensus constraint. We also propose a Gauss-Seidel type discretization scheme for the proposed method and establish its linear convergence rate. For certain classes of problems we identify mirror maps that mitigate the effect of the graph's spectral properties on the convergence rate of the algorithm. Using numerical experiments we demonstrate the efficiency of the methodology on convex models, both with and without constraints. Our findings show that the proposed method outperforms other methods, especially in scenarios where the model's geometry is not captured by the standard Euclidean norm
format Preprint
id arxiv_https___arxiv_org_abs_2201_08642
institution arXiv
publishDate 2022
record_format arxiv
spellingShingle Stochastic Mirror Descent for Convex Optimization with Consensus Constraints
Borovykh, Anastasia
Kantas, Nikolas
Parpas, Panos
Pavliotis, Grigorios A.
Optimization and Control
65K10, 68Q87, 60G07, 68W15
The mirror descent algorithm is known to be effective in situations where it is beneficial to adapt the mirror map to the underlying geometry of the optimization model. However, the effect of mirror maps on the geometry of distributed optimization problems has not been previously addressed. In this paper we study an exact distributed mirror descent algorithm in continuous-time under additive noise. We establish a linear convergence rate of the proposed dynamics for the setting of convex optimization. Our analysis draws motivation from the Augmented Lagrangian and its relation to gradient tracking. To further explore the benefits of mirror maps in a distributed setting we present a preconditioned variant of our algorithm with an additional mirror map over the Lagrangian dual variables. This allows our method to adapt to both the geometry of the primal variables, as well as to the geometry of the consensus constraint. We also propose a Gauss-Seidel type discretization scheme for the proposed method and establish its linear convergence rate. For certain classes of problems we identify mirror maps that mitigate the effect of the graph's spectral properties on the convergence rate of the algorithm. Using numerical experiments we demonstrate the efficiency of the methodology on convex models, both with and without constraints. Our findings show that the proposed method outperforms other methods, especially in scenarios where the model's geometry is not captured by the standard Euclidean norm
title Stochastic Mirror Descent for Convex Optimization with Consensus Constraints
topic Optimization and Control
65K10, 68Q87, 60G07, 68W15
url https://arxiv.org/abs/2201.08642