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arXiv · 0812.2599

Learning Low Rank Matrices from O(n) Entries

Raghunandan H. Keshavan·Andrea Montanari·Sewoong Oh
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Abstract

How many random entries of an n by m, rank r matrix are necessary to reconstruct the matrix within an accuracy d? We address this question in the case of a random matrix with bounded rank, whereby the observed entries are chosen uniformly at random. We prove that, for any d>0, C(r,d)n observations are sufficient. Finally we discuss the question of reconstructing the matrix efficiently, and demonstrate through extensive simulations that this task can be accomplished in nPoly(log n) operations, for small rank.

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BibTeXRIS

Raghunandan H. Keshavan, Andrea Montanari, Sewoong Oh. 2008-12-14. Learning Low Rank Matrices from O(n) Entries. https://arxiv.org/abs/0812.2599

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