A measure approximation theorem for Wasserstein-robust expected values

Abstract

We consider the problem of finding the infimum, over probability measures being in a ball defined by Wasserstein distance, of the expected value of a bounded Lipschitz random variable on ${\mathbf{R}}^d$. We show that if the $\sigma -$algebra is approximated in by a sequence of $\sigma$-algebras in a certain natural sense, then the solutions of the induced approximated minimization problems converge to that of the initial minimization problem.