Ou, Z;
Zhang, M;
Zhang, A;
Xiao, TZ;
Li, Y;
Barber, D;
(2025)
Improving Probabilistic Diffusion Models With Optimal Diagonal Covariance Matching.
In:
Proceedings of the International Conference on Representation Learning 2025 (ICLR 2025).
(pp. pp. 36922-36947).
ICLR
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Abstract
The probabilistic diffusion model has become highly effective across various domains. Typically, sampling from a diffusion model involves using a denoising distribution characterized by a Gaussian with a learned mean and either fixed or learned covariances. In this paper, we leverage the recently proposed covariance moment matching technique and introduce a novel method for learning the diagonal covariance. Unlike traditional data-driven diagonal covariance approximation approaches, our method involves directly regressing the optimal diagonal analytic covariance using a new, unbiased objective named Optimal Covariance Matching (OCM). This approach can significantly reduce the approximation error in covariance prediction. We demonstrate how our method can substantially enhance the sampling efficiency, recall rate and likelihood of commonly used diffusion models.
| Type: | Proceedings paper |
|---|---|
| Title: | Improving Probabilistic Diffusion Models With Optimal Diagonal Covariance Matching |
| Event: | International Conference on Representation Learning 2025 (ICLR 2025) |
| Open access status: | An open access version is available from UCL Discovery |
| Publisher version: | https://proceedings.iclr.cc/paper_files/paper/2025 |
| Language: | English |
| Additional information: | © The Authors 2025. Original content in this paper is licensed under the terms of the Creative Commons Attribution 4.0 International (CC BY-NC 4.0) Licence (https://creativecommons.org/licenses/by/4.0/deed.en). |
| UCL classification: | UCL UCL > Provost and Vice Provost Offices > UCL BEAMS UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Engineering Science > Dept of Computer Science |
| URI: | https://discovery.ucl.ac.uk/id/eprint/10211966 |
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