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arXiv · 2407.07998

What's the score? Automated Denoising Score Matching for Nonlinear Diffusions

Abstract

Reversing a diffusion process by learning its score forms the heart of diffusion-based generative modeling and for estimating properties of scientific systems. The diffusion processes that are tractable center on linear processes with a Gaussian stationary distribution. This limits the kinds of models that can be built to those that target a Gaussian prior or more generally limits the kinds of problems that can be generically solved to those that have conditionally linear score functions. In this work, we introduce a family of tractable denoising score matching objectives, called local-DSM, built using local increments of the diffusion process. We show how local-DSM melded with Taylor expansions enables automated training and score estimation with nonlinear diffusion processes. To demonstrate these ideas, we use automated-DSM to train generative models using non-Gaussian priors on challenging low dimensional distributions and the CIFAR10 image dataset. Additionally, we use the automated-DSM to learn the scores for nonlinear processes studied in statistical physics.

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BibTeXRIS

Raghav Singhal, Mark Goldstein, Rajesh Ranganath. 2024-07-10. What's the score? Automated Denoising Score Matching for Nonlinear Diffusions. https://arxiv.org/abs/2407.07998

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