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arXiv · 1502.01403

Distributed Estimation of Generalized Matrix Rank: Efficient Algorithms and Lower Bounds

Abstract

We study the following generalized matrix rank estimation problem: given an $n \times n$ matrix and a constant $c \geq 0$, estimate the number of eigenvalues that are greater than $c$. In the distributed setting, the matrix of interest is the sum of $m$ matrices held by separate machines. We show that any deterministic algorithm solving this problem must communicate $Ω(n^2)$ bits, which is order-equivalent to transmitting the whole matrix. In contrast, we propose a randomized algorithm that communicates only $\widetilde O(n)$ bits. The upper bound is matched by an $Ω(n)$ lower bound on the randomized communication complexity. We demonstrate the practical effectiveness of the proposed algorithm with some numerical experiments.

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BibTeXRIS

Yuchen Zhang, Martin J. Wainwright, Michael I. Jordan. 2015-02-06. Distributed Estimation of Generalized Matrix Rank: Efficient Algorithms and Lower Bounds. https://arxiv.org/abs/1502.01403

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