More Efficient Sampling for Tensor Decomposition With Worst-Case Guarantees

Osman Asif Malik

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arXiv · 2110.07631

More Efficient Sampling for Tensor Decomposition With Worst-Case Guarantees

Osman Asif Malik

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Abstract

Recent papers have developed alternating least squares (ALS) methods for CP and tensor ring decomposition with a per-iteration cost which is sublinear in the number of input tensor entries for low-rank decomposition. However, the per-iteration cost of these methods still has an exponential dependence on the number of tensor modes when parameters are chosen to achieve certain worst-case guarantees. In this paper, we propose sampling-based ALS methods for the CP and tensor ring decompositions whose cost does not have this exponential dependence, thereby significantly improving on the previous state-of-the-art. We provide a detailed theoretical analysis and also apply the methods in a feature extraction experiment.

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Osman Asif Malik. 2021-10-14. More Efficient Sampling for Tensor Decomposition With Worst-Case Guarantees. https://arxiv.org/abs/2110.07631

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