Approximation rates of entropic maps in semidiscrete optimal transport

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Sadhu, Ritwik, Goldfeld, Ziv, Kato, Kengo
Natura: Preprint
Pubblicazione: 2024
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866916491091247104
author Sadhu, Ritwik
Goldfeld, Ziv
Kato, Kengo
author_facet Sadhu, Ritwik
Goldfeld, Ziv
Kato, Kengo
contents Entropic optimal transport offers a computationally tractable approximation to the classical problem. In this note, we study the approximation rate of the entropic optimal transport map (in approaching the Brenier map) when the regularization parameter $\varepsilon$ tends to zero in the semidiscrete setting, where the input measure is absolutely continuous while the output is finitely discrete. Previous work shows that the approximation rate is $O(\sqrt{\varepsilon})$ under the $L^2$-norm with respect to the input measure. In this work, we establish faster, $O(\varepsilon^2)$ rates up to polylogarithmic factors, under the dual Lipschitz norm, which is weaker than the $L^2$-norm. For the said dual norm, the $O(\varepsilon^2)$ rate is sharp. As a corollary, we derive a central limit theorem for the entropic estimator for the Brenier map in the dual Lipschitz space when the regularization parameter tends to zero as the sample size increases.
format Preprint
id arxiv_https___arxiv_org_abs_2411_07947
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Approximation rates of entropic maps in semidiscrete optimal transport
Sadhu, Ritwik
Goldfeld, Ziv
Kato, Kengo
Probability
Optimization and Control
49Q22, 60F05, 49N15
Entropic optimal transport offers a computationally tractable approximation to the classical problem. In this note, we study the approximation rate of the entropic optimal transport map (in approaching the Brenier map) when the regularization parameter $\varepsilon$ tends to zero in the semidiscrete setting, where the input measure is absolutely continuous while the output is finitely discrete. Previous work shows that the approximation rate is $O(\sqrt{\varepsilon})$ under the $L^2$-norm with respect to the input measure. In this work, we establish faster, $O(\varepsilon^2)$ rates up to polylogarithmic factors, under the dual Lipschitz norm, which is weaker than the $L^2$-norm. For the said dual norm, the $O(\varepsilon^2)$ rate is sharp. As a corollary, we derive a central limit theorem for the entropic estimator for the Brenier map in the dual Lipschitz space when the regularization parameter tends to zero as the sample size increases.
title Approximation rates of entropic maps in semidiscrete optimal transport
topic Probability
Optimization and Control
49Q22, 60F05, 49N15
url https://arxiv.org/abs/2411.07947