Understanding Generalization in Diffusion Models via Probability Flow Distance
- URL: http://arxiv.org/abs/2505.20123v1
- Date: Mon, 26 May 2025 15:23:50 GMT
- Title: Understanding Generalization in Diffusion Models via Probability Flow Distance
- Authors: Huijie Zhang, Zijian Huang, Siyi Chen, Jinfan Zhou, Zekai Zhang, Peng Wang, Qing Qu,
- Abstract summary: We introduce probability flow distance ($texttPFD$) to measure distributional generalization.<n>We empirically uncover several key generalization behaviors in diffusion models.
- Score: 7.675910526644439
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: Diffusion models have emerged as a powerful class of generative models, capable of producing high-quality samples that generalize beyond the training data. However, evaluating this generalization remains challenging: theoretical metrics are often impractical for high-dimensional data, while no practical metrics rigorously measure generalization. In this work, we bridge this gap by introducing probability flow distance ($\texttt{PFD}$), a theoretically grounded and computationally efficient metric to measure distributional generalization. Specifically, $\texttt{PFD}$ quantifies the distance between distributions by comparing their noise-to-data mappings induced by the probability flow ODE. Moreover, by using $\texttt{PFD}$ under a teacher-student evaluation protocol, we empirically uncover several key generalization behaviors in diffusion models, including: (1) scaling behavior from memorization to generalization, (2) early learning and double descent training dynamics, and (3) bias-variance decomposition. Beyond these insights, our work lays a foundation for future empirical and theoretical studies on generalization in diffusion models.
Related papers
- Generalization through variance: how noise shapes inductive biases in diffusion models [0.0]
We develop a mathematical theory that partly explains 'generalization through variance' phenomenon.<n>We find that the distributions diffusion models effectively learn to sample from resemble their training distributions.<n>We also characterize how this inductive bias interacts with feature-related inductive biases.
arXiv Detail & Related papers (2025-04-16T23:41:10Z) - Learning Divergence Fields for Shift-Robust Graph Representations [73.11818515795761]
In this work, we propose a geometric diffusion model with learnable divergence fields for the challenging problem with interdependent data.
We derive a new learning objective through causal inference, which can guide the model to learn generalizable patterns of interdependence that are insensitive across domains.
arXiv Detail & Related papers (2024-06-07T14:29:21Z) - Unveil Conditional Diffusion Models with Classifier-free Guidance: A Sharp Statistical Theory [87.00653989457834]
Conditional diffusion models serve as the foundation of modern image synthesis and find extensive application in fields like computational biology and reinforcement learning.
Despite the empirical success, theory of conditional diffusion models is largely missing.
This paper bridges the gap by presenting a sharp statistical theory of distribution estimation using conditional diffusion models.
arXiv Detail & Related papers (2024-03-18T17:08:24Z) - On the Generalization Properties of Diffusion Models [31.067038651873126]
This work embarks on a comprehensive theoretical exploration of the generalization attributes of diffusion models.<n>We establish theoretical estimates of the generalization gap that evolves in tandem with the training dynamics of score-based diffusion models.<n>We extend our quantitative analysis to a data-dependent scenario, wherein target distributions are portrayed as a succession of densities.
arXiv Detail & Related papers (2023-11-03T09:20:20Z) - Towards Faster Non-Asymptotic Convergence for Diffusion-Based Generative
Models [49.81937966106691]
We develop a suite of non-asymptotic theory towards understanding the data generation process of diffusion models.
In contrast to prior works, our theory is developed based on an elementary yet versatile non-asymptotic approach.
arXiv Detail & Related papers (2023-06-15T16:30:08Z) - On the Generalization of Diffusion Model [42.447639515467934]
We define the generalization of the generative model, which is measured by the mutual information between the generated data and the training set.
We show that for the empirical optimal diffusion model, the data generated by a deterministic sampler are all highly related to the training set, thus poor generalization.
We propose another training objective whose empirical optimal solution has no potential generalization problem.
arXiv Detail & Related papers (2023-05-24T04:27:57Z) - Diffusion Models are Minimax Optimal Distribution Estimators [49.47503258639454]
We provide the first rigorous analysis on approximation and generalization abilities of diffusion modeling.
We show that when the true density function belongs to the Besov space and the empirical score matching loss is properly minimized, the generated data distribution achieves the nearly minimax optimal estimation rates.
arXiv Detail & Related papers (2023-03-03T11:31:55Z) - Counterfactual Maximum Likelihood Estimation for Training Deep Networks [83.44219640437657]
Deep learning models are prone to learning spurious correlations that should not be learned as predictive clues.
We propose a causality-based training framework to reduce the spurious correlations caused by observable confounders.
We conduct experiments on two real-world tasks: Natural Language Inference (NLI) and Image Captioning.
arXiv Detail & Related papers (2021-06-07T17:47:16Z) - Generalization and Memorization: The Bias Potential Model [9.975163460952045]
generative models and density estimators behave quite differently from models for learning functions.
For the bias potential model, we show that dimension-independent generalization accuracy is achievable if early stopping is adopted.
In the long term, the model either memorizes the samples or diverges.
arXiv Detail & Related papers (2020-11-29T04:04:54Z) - Good Classifiers are Abundant in the Interpolating Regime [64.72044662855612]
We develop a methodology to compute precisely the full distribution of test errors among interpolating classifiers.
We find that test errors tend to concentrate around a small typical value $varepsilon*$, which deviates substantially from the test error of worst-case interpolating model.
Our results show that the usual style of analysis in statistical learning theory may not be fine-grained enough to capture the good generalization performance observed in practice.
arXiv Detail & Related papers (2020-06-22T21:12:31Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.