FROST—Fast row-stochastic optimization with uncoordinated step-sizes

Autor: Usman A. Khan, Ran Xin, Chenguang Xi
Rok vydání: 2019
Předmět:
Zdroj: EURASIP Journal on Advances in Signal Processing, Vol 2019, Iss 1, Pp 1-14 (2019)
ISSN: 1687-6180
DOI: 10.1186/s13634-018-0596-y
Popis: In this paper, we discuss distributed optimization over directed graphs, where doubly-stochastic weights cannot be constructed. Most of the existing algorithms overcome this issue by applying push-sum consensus, which utilizes column-stochastic weights. The formulation of column-stochastic weights requires each agent to know (at least) its out-degree, which may be impractical in e.g., broadcast-based communication protocols. In contrast, we describe FROST (Fast Row-stochastic-Optimization with uncoordinated STep-sizes), an optimization algorithm applicable to directed graphs that does not require the knowledge of out-degrees; the implementation of which is straightforward as each agent locally assigns weights to the incoming information and locally chooses a suitable step-size. We show that FROST converges linearly to the optimal solution for smooth and strongly-convex functions given that the largest step-size is positive and sufficiently small.
Comment: Submitted for journal publication, currently under review
Databáze: OpenAIRE