An analysis of the noise schedule for score-based generative models

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Strasman, Stanislas, Ocello, Antonio, Boyer, Claire, Corff, Sylvain Le, Lemaire, Vincent
Natura: Preprint
Pubblicazione: 2024
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866916582517637120
author Strasman, Stanislas
Ocello, Antonio
Boyer, Claire
Corff, Sylvain Le
Lemaire, Vincent
author_facet Strasman, Stanislas
Ocello, Antonio
Boyer, Claire
Corff, Sylvain Le
Lemaire, Vincent
contents Score-based generative models (SGMs) aim at estimating a target data distribution by learning score functions using only noise-perturbed samples from the target.Recent literature has focused extensively on assessing the error between the target and estimated distributions, gauging the generative quality through the Kullback-Leibler (KL) divergence and Wasserstein distances. Under mild assumptions on the data distribution, we establish an upper bound for the KL divergence between the target and the estimated distributions, explicitly depending on any time-dependent noise schedule. Under additional regularity assumptions, taking advantage of favorable underlying contraction mechanisms, we provide a tighter error bound in Wasserstein distance compared to state-of-the-art results. In addition to being tractable, this upper bound jointly incorporates properties of the target distribution and SGM hyperparameters that need to be tuned during training. Finally, we illustrate these bounds through numerical experiments using simulated and CIFAR-10 datasets, identifying an optimal range of noise schedules within a parametric family.
format Preprint
id arxiv_https___arxiv_org_abs_2402_04650
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle An analysis of the noise schedule for score-based generative models
Strasman, Stanislas
Ocello, Antonio
Boyer, Claire
Corff, Sylvain Le
Lemaire, Vincent
Statistics Theory
Machine Learning
Score-based generative models (SGMs) aim at estimating a target data distribution by learning score functions using only noise-perturbed samples from the target.Recent literature has focused extensively on assessing the error between the target and estimated distributions, gauging the generative quality through the Kullback-Leibler (KL) divergence and Wasserstein distances. Under mild assumptions on the data distribution, we establish an upper bound for the KL divergence between the target and the estimated distributions, explicitly depending on any time-dependent noise schedule. Under additional regularity assumptions, taking advantage of favorable underlying contraction mechanisms, we provide a tighter error bound in Wasserstein distance compared to state-of-the-art results. In addition to being tractable, this upper bound jointly incorporates properties of the target distribution and SGM hyperparameters that need to be tuned during training. Finally, we illustrate these bounds through numerical experiments using simulated and CIFAR-10 datasets, identifying an optimal range of noise schedules within a parametric family.
title An analysis of the noise schedule for score-based generative models
topic Statistics Theory
Machine Learning
url https://arxiv.org/abs/2402.04650