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Accelerating Block Coordinate Descent for Nonnegative Tensor Factorization

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 نشر من قبل Man Shun Ang
 تاريخ النشر 2020
  مجال البحث الهندسة المعلوماتية
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This paper is concerned with improving the empirical convergence speed of block-coordinate descent algorithms for approximate nonnegative tensor factorization (NTF). We propose an extrapolation strategy in-between block updates, referred to as heuristic extrapolation with restarts (HER). HER significantly accelerates the empirical convergence speed of most existing block-coordinate algorithms for dense NTF, in particular for challenging computational scenarios, while requiring a negligible additional computational budget.

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