Online Posterior Sampling with a Diffusion Prior

Fuente: arXiv
Guardado en:
Detalles Bibliográficos
Autores principales: Kveton, Branislav, Oreshkin, Boris, Park, Youngsuk, Deshmukh, Aniket, Song, Rui
Formato: Preprint
Publicado: 2024
Materias:
Acceso en línea:
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
_version_ 1866914330107183104
author Kveton, Branislav
Oreshkin, Boris
Park, Youngsuk
Deshmukh, Aniket
Song, Rui
author_facet Kveton, Branislav
Oreshkin, Boris
Park, Youngsuk
Deshmukh, Aniket
Song, Rui
contents Posterior sampling in contextual bandits with a Gaussian prior can be implemented exactly or approximately using the Laplace approximation. The Gaussian prior is computationally efficient but it cannot describe complex distributions. In this work, we propose approximate posterior sampling algorithms for contextual bandits with a diffusion model prior. The key idea is to sample from a chain of approximate conditional posteriors, one for each stage of the reverse diffusion process, which are obtained by the Laplace approximation. Our approximations are motivated by posterior sampling with a Gaussian prior, and inherit its simplicity and efficiency. They are asymptotically consistent and perform well empirically on a variety of contextual bandit problems.
format Preprint
id arxiv_https___arxiv_org_abs_2410_03919
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Online Posterior Sampling with a Diffusion Prior
Kveton, Branislav
Oreshkin, Boris
Park, Youngsuk
Deshmukh, Aniket
Song, Rui
Machine Learning
Posterior sampling in contextual bandits with a Gaussian prior can be implemented exactly or approximately using the Laplace approximation. The Gaussian prior is computationally efficient but it cannot describe complex distributions. In this work, we propose approximate posterior sampling algorithms for contextual bandits with a diffusion model prior. The key idea is to sample from a chain of approximate conditional posteriors, one for each stage of the reverse diffusion process, which are obtained by the Laplace approximation. Our approximations are motivated by posterior sampling with a Gaussian prior, and inherit its simplicity and efficiency. They are asymptotically consistent and perform well empirically on a variety of contextual bandit problems.
title Online Posterior Sampling with a Diffusion Prior
topic Machine Learning
url https://arxiv.org/abs/2410.03919