Spurious Valleys, Spurious Minima and NP-hardness of Sparse Matrix Factorization With Fixed Support
Spurious Valleys, Spurious Minima and NP-hardness of Sparse Matrix Factorization With Fixed Support
The problem of approximating a dense matrix by a product of sparse factors is a fundamental problem for many signal processing and machine learning tasks. It can be decomposed into two subproblems: finding the position of the non-zero coefficients in the sparse factors, and determining their values. While the first …