Graph balancing for distributed subgradient methods over directed graphs

We consider a multi agent optimization problem where a set of agents collectively solves a global optimization problem with the objective function given by the sum of locally known convex functions. We focus on the case when information exchange among agents takes place over a directed network and p...

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Main Authors: Makhdoumi Kakhaki, Ali, Koksal, Asuman E.
Other Authors: Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science
Format: Article
Language:en_US
Published: Institute of Electrical and Electronics Engineers (IEEE) 2017
Online Access:http://hdl.handle.net/1721.1/111685
https://orcid.org/0000-0002-1827-1285
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author Makhdoumi Kakhaki, Ali
Koksal, Asuman E.
author2 Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science
author_facet Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science
Makhdoumi Kakhaki, Ali
Koksal, Asuman E.
author_sort Makhdoumi Kakhaki, Ali
collection MIT
description We consider a multi agent optimization problem where a set of agents collectively solves a global optimization problem with the objective function given by the sum of locally known convex functions. We focus on the case when information exchange among agents takes place over a directed network and propose a distributed subgradient algorithm in which each agent performs local processing based on information obtained from his incoming neighbors. Our algorithm uses weight balancing to overcome the asymmetries caused by the directed communication network, i.e., agents scale their outgoing information with dynamically updated weights that converge to balancing weights of the graph. We show that both the objective function values and the consensus violation, at the ergodic average of the estimates generated by the algorithm, converge with rate equation, where T is the number of iterations. A special case of our algorithm provides a new distributed method to compute average consensus over directed graphs.
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spelling mit-1721.1/1116852022-10-01T11:56:59Z Graph balancing for distributed subgradient methods over directed graphs Makhdoumi Kakhaki, Ali Koksal, Asuman E. Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science Makhdoumi Kakhaki, Ali Koksal, Asuman E. We consider a multi agent optimization problem where a set of agents collectively solves a global optimization problem with the objective function given by the sum of locally known convex functions. We focus on the case when information exchange among agents takes place over a directed network and propose a distributed subgradient algorithm in which each agent performs local processing based on information obtained from his incoming neighbors. Our algorithm uses weight balancing to overcome the asymmetries caused by the directed communication network, i.e., agents scale their outgoing information with dynamically updated weights that converge to balancing weights of the graph. We show that both the objective function values and the consensus violation, at the ergodic average of the estimates generated by the algorithm, converge with rate equation, where T is the number of iterations. A special case of our algorithm provides a new distributed method to compute average consensus over directed graphs. 2017-10-03T18:58:05Z 2017-10-03T18:58:05Z 2016-02 Article http://purl.org/eprint/type/ConferencePaper 978-1-4799-7886-1 http://hdl.handle.net/1721.1/111685 Makhdoumi, Ali, and Ozdaglar, Asuman. “Graph Balancing for Distributed Subgradient Methods over Directed Graphs.” 2015 54th IEEE Conference on Decision and Control (CDC), December 15-18 2015, Osaka, Japan, Institute of Electrical and Electronics Engineers (IEEE), February 2016: 1364-1371 © 2015 Institute of Electrical and Electronics Engineers (IEEE) https://orcid.org/0000-0002-1827-1285 en_US http://dx.doi.org/10.1109/CDC.2015.7402401 2015 54th IEEE Conference on Decision and Control (CDC) Creative Commons Attribution-Noncommercial-Share Alike http://creativecommons.org/licenses/by-nc-sa/4.0/ application/pdf Institute of Electrical and Electronics Engineers (IEEE) MIT Web Domain
spellingShingle Makhdoumi Kakhaki, Ali
Koksal, Asuman E.
Graph balancing for distributed subgradient methods over directed graphs
title Graph balancing for distributed subgradient methods over directed graphs
title_full Graph balancing for distributed subgradient methods over directed graphs
title_fullStr Graph balancing for distributed subgradient methods over directed graphs
title_full_unstemmed Graph balancing for distributed subgradient methods over directed graphs
title_short Graph balancing for distributed subgradient methods over directed graphs
title_sort graph balancing for distributed subgradient methods over directed graphs
url http://hdl.handle.net/1721.1/111685
https://orcid.org/0000-0002-1827-1285
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