collaborators

6 papers

math.OC2026

Optimization on the Oblique Manifold for Sparse Simplex Constraints via Multiplicative Updates

Flavia Esposito, Andersen Ang

Low-rank optimization problems with sparse simplex constraints involve variables that must satisfy nonnegativity, sparsity, and sum-to-1 conditions, making their optimization parti…

math.NA2026

Optimal Network Pricing for Oblivious Users under Projected Decision-Dependent Distributions

Yixuan Li, Andersen Ang, Sebastian Stein

Efficient large-scale network allocation requires data-driven pricing mechanisms that internalize stochastic, nonlinear user behavior. We move beyond the classic fully strategic ag…

math.OC2026

Binno: A 1st-order method for Bi-level Nonconvex Nonsmooth Optimization for Matrix Factorizations

Laura Selicato, Flavia Esposito, Andersen Ang

Nonconvex and nonsmooth bi-level optimization poses critical theoretical challenges, while arising in several applications. In this work, we develop a method for nonconvex, nonsmoo…

cs.LG2025

Sparse Hyperparametric Itakura-Saito Nonnegative Matrix Factorization via Bi-Level Optimization

Laura Selicato, Flavia Esposito, Andersen Ang +2

The selection of penalty hyperparameters is a critical aspect in Nonnegative Matrix Factorization (NMF), since these values control the trade-off between reconstruction accuracy an…

cs.LG2025

Sum-of-norms regularized Nonnegative Matrix Factorization

Andersen Ang, Waqas Bin Hamed, Hans De Sterck

When applying nonnegative matrix factorization (NMF), the rank parameter is generally unknown. This rank, called the nonnegative rank, is usually estimated heuristically since comp…

math.OC2025

Chordal-NMF with Riemannian Multiplicative Update

Flavia Esposito, Andersen Ang

Nonnegative Matrix Factorization (NMF) is the problem of approximating a given nonnegative matrix M through the product of two nonnegative low-rank matrices W and H. Traditionally…