Exact Conditional Score-Guided Generative Modeling for Amortized Inference in Uncertainty Quantification

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Zhang, Zezhong, Tatsuoka, Caroline, Xiu, Dongbin, Zhang, Guannan
Natura: Preprint
Pubblicazione: 2025
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866911018921230336
author Zhang, Zezhong
Tatsuoka, Caroline
Xiu, Dongbin
Zhang, Guannan
author_facet Zhang, Zezhong
Tatsuoka, Caroline
Xiu, Dongbin
Zhang, Guannan
contents We propose an efficient framework for amortized conditional inference by leveraging exact conditional score-guided diffusion models to train a non-reversible neural network as a conditional generative model. Traditional normalizing flow methods require reversible architectures, which can limit their expressiveness and efficiency. Although diffusion models offer greater flexibility, they often suffer from high computational costs during inference. To combine the strengths of both approaches, we introduce a two-stage method. First, we construct a training-free conditional diffusion model by analytically deriving an exact score function under a Gaussian mixture prior formed from samples of the underlying joint distribution. This exact conditional score model allows us to efficiently generate noise-labeled data, consisting of initial diffusion Gaussian noise and posterior samples conditioned on various observation values, by solving a reverse-time ordinary differential equation. Second, we use this noise-labeled data to train a feedforward neural network that maps noise and observations directly to posterior samples, eliminating the need for reversibility or iterative sampling at inference time. The resulting model provides fast, accurate, and scalable conditional sampling for high-dimensional and multi-modal posterior distributions, making it well-suited for uncertainty quantification tasks, e.g., parameter estimation of complex physical systems. We demonstrate the effectiveness of our approach through a series of numerical experiments.
format Preprint
id arxiv_https___arxiv_org_abs_2506_18227
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Exact Conditional Score-Guided Generative Modeling for Amortized Inference in Uncertainty Quantification
Zhang, Zezhong
Tatsuoka, Caroline
Xiu, Dongbin
Zhang, Guannan
Computational Engineering, Finance, and Science
We propose an efficient framework for amortized conditional inference by leveraging exact conditional score-guided diffusion models to train a non-reversible neural network as a conditional generative model. Traditional normalizing flow methods require reversible architectures, which can limit their expressiveness and efficiency. Although diffusion models offer greater flexibility, they often suffer from high computational costs during inference. To combine the strengths of both approaches, we introduce a two-stage method. First, we construct a training-free conditional diffusion model by analytically deriving an exact score function under a Gaussian mixture prior formed from samples of the underlying joint distribution. This exact conditional score model allows us to efficiently generate noise-labeled data, consisting of initial diffusion Gaussian noise and posterior samples conditioned on various observation values, by solving a reverse-time ordinary differential equation. Second, we use this noise-labeled data to train a feedforward neural network that maps noise and observations directly to posterior samples, eliminating the need for reversibility or iterative sampling at inference time. The resulting model provides fast, accurate, and scalable conditional sampling for high-dimensional and multi-modal posterior distributions, making it well-suited for uncertainty quantification tasks, e.g., parameter estimation of complex physical systems. We demonstrate the effectiveness of our approach through a series of numerical experiments.
title Exact Conditional Score-Guided Generative Modeling for Amortized Inference in Uncertainty Quantification
topic Computational Engineering, Finance, and Science
url https://arxiv.org/abs/2506.18227