Friday, January 29th at 10:30, Kaie Kubjas (University of Aalto).

Exact solutions in low-rank approximation with zeros
Abstract:  Low-rank approximation with zeros aims to find a matrix of fixed rank and with a fixed zero pattern that minimizes the Euclidean distance to a given data matrix. We study the critical points of this optimization problem using algebraic tools. In particular, we describe special linear, affine and determinantal relations satisfied by the critical points. We also investigate the number of critical points and how the number is related to the complexity of nonnegative matrix factorization problem. This talk is based on a recent preprint together with Luca Sodomaco and Elias Tsigaridas.

The seminar will take place online. Click here for the Zoom link.