Sampling, Diffusions, and Stochastic Localization
- URL: http://arxiv.org/abs/2305.10690v2
- Date: Tue, 02 Sep 2025 12:50:49 GMT
- Title: Sampling, Diffusions, and Stochastic Localization
- Authors: Andrea Montanari,
- Abstract summary: Diffusions are a successful technique to sample from high-dimensional expository distributions.<n>The drift of the diffusion process is typically represented as a neural network.<n>An algorithmic version of Markov localization was recently proposed in order to sample from certain statistical mechanics models.
- Score: 10.871336306134395
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Diffusions are a successful technique to sample from high-dimensional distributions. The target distribution can be either explicitly given or learnt from a collection of samples. They implement a diffusion process whose endpoint is a sample from the target distribution. The drift of the diffusion process is typically represented as a neural network. Stochastic localization is a successful technique to prove mixing of Markov Chains and other functional inequalities in high dimension. An algorithmic version of stochastic localization was recently proposed in order to sample from certain statistical mechanics models. This expository article has three objectives: $(i)$~Generalize the algorithmic construction to other stochastic localization processes. This construction is both simple and broadly applicable; $(ii)$~Clarify the connection between diffusions and stochastic localization. This allows to derive several known sampling schemes in a unified fashion; $(iii)$~Describe the insights that follow from this unified viewpoint.
Related papers
- Distillation of Discrete Diffusion by Exact Conditional Distribution Matching [9.460409527892345]
We propose a simple and principled distillation alternative based on emphconditional distribution matching.<n>We exploit this structure to define distillation objectives that directly match conditional distributions between a pre-trained teacher and a low-NFE student.
arXiv Detail & Related papers (2025-12-15T00:16:10Z) - Debiasing Guidance for Discrete Diffusion with Sequential Monte Carlo [15.333834240761048]
We introduce a Sequential Monte Carlo algorithm that generates unbiasedly from a target distribution.<n>We validate our approach on low-dimensional distributions, controlled images and text generations.
arXiv Detail & Related papers (2025-02-10T00:27:54Z) - Sampling in High-Dimensions using Stochastic Interpolants and Forward-Backward Stochastic Differential Equations [8.509310102094512]
We present a class of diffusion-based algorithms to draw samples from high-dimensional probability distributions.
Our approach relies on the interpolants framework to define a time-indexed collection of probability densities.
We demonstrate that our algorithm can effectively draw samples from distributions that conventional methods struggle to handle.
arXiv Detail & Related papers (2025-02-01T07:27:11Z) - Learned Reference-based Diffusion Sampling for multi-modal distributions [2.1383136715042417]
We introduce Learned Reference-based Diffusion Sampler (LRDS), a methodology specifically designed to leverage prior knowledge on the location of the target modes.
LRDS proceeds in two steps by learning a reference diffusion model on samples located in high-density space regions.
We experimentally demonstrate that LRDS best exploits prior knowledge on the target distribution compared to competing algorithms on a variety of challenging distributions.
arXiv Detail & Related papers (2024-10-25T10:23:34Z) - Unified Convergence Analysis for Score-Based Diffusion Models with Deterministic Samplers [49.1574468325115]
We introduce a unified convergence analysis framework for deterministic samplers.
Our framework achieves iteration complexity of $tilde O(d2/epsilon)$.
We also provide a detailed analysis of Denoising Implicit Diffusion Models (DDIM)-type samplers.
arXiv Detail & Related papers (2024-10-18T07:37:36Z) - Theory on Score-Mismatched Diffusion Models and Zero-Shot Conditional Samplers [49.97755400231656]
We present the first performance guarantee with explicit dimensional general score-mismatched diffusion samplers.
We show that score mismatches result in an distributional bias between the target and sampling distributions, proportional to the accumulated mismatch between the target and training distributions.
This result can be directly applied to zero-shot conditional samplers for any conditional model, irrespective of measurement noise.
arXiv Detail & Related papers (2024-10-17T16:42:12Z) - Conditional sampling within generative diffusion models [12.608803080528142]
We present a review of existing computational approaches to conditional sampling within generative diffusion models.
We highlight key methodologies that either utilise the joint distribution, or rely on (pre-trained) marginal distributions with explicit likelihoods.
arXiv Detail & Related papers (2024-09-15T07:48:40Z) - Theoretical Insights for Diffusion Guidance: A Case Study for Gaussian
Mixture Models [59.331993845831946]
Diffusion models benefit from instillation of task-specific information into the score function to steer the sample generation towards desired properties.
This paper provides the first theoretical study towards understanding the influence of guidance on diffusion models in the context of Gaussian mixture models.
arXiv Detail & Related papers (2024-03-03T23:15:48Z) - Stochastic Localization via Iterative Posterior Sampling [2.1383136715042417]
We consider a general localization framework and introduce an explicit class of observation processes, associated with flexible denoising schedules.
We provide a complete methodology, $textitStochastic localization via Iterative Posterior Sampling$ (SLIPS), to obtain approximate samples of this dynamics, and as a byproduct, samples from the target distribution.
We illustrate the benefits and applicability of SLIPS on several benchmarks of multi-modal distributions, including mixtures in increasing dimensions, logistic regression and high-dimensional field system from statistical-mechanics.
arXiv Detail & Related papers (2024-02-16T15:28:41Z) - Improved off-policy training of diffusion samplers [93.66433483772055]
We study the problem of training diffusion models to sample from a distribution with an unnormalized density or energy function.
We benchmark several diffusion-structured inference methods, including simulation-based variational approaches and off-policy methods.
Our results shed light on the relative advantages of existing algorithms while bringing into question some claims from past work.
arXiv Detail & Related papers (2024-02-07T18:51:49Z) - Distributed Markov Chain Monte Carlo Sampling based on the Alternating
Direction Method of Multipliers [143.6249073384419]
In this paper, we propose a distributed sampling scheme based on the alternating direction method of multipliers.
We provide both theoretical guarantees of our algorithm's convergence and experimental evidence of its superiority to the state-of-the-art.
In simulation, we deploy our algorithm on linear and logistic regression tasks and illustrate its fast convergence compared to existing gradient-based methods.
arXiv Detail & Related papers (2024-01-29T02:08:40Z) - Blackout Diffusion: Generative Diffusion Models in Discrete-State Spaces [0.0]
We develop a theoretical formulation for arbitrary discrete-state Markov processes in the forward diffusion process.
As an example, we introduce Blackout Diffusion'', which learns to produce samples from an empty image instead of from noise.
arXiv Detail & Related papers (2023-05-18T16:24:12Z) - Unsupervised Learning of Sampling Distributions for Particle Filters [80.6716888175925]
We put forward four methods for learning sampling distributions from observed measurements.
Experiments demonstrate that learned sampling distributions exhibit better performance than designed, minimum-degeneracy sampling distributions.
arXiv Detail & Related papers (2023-02-02T15:50:21Z) - Score-based Continuous-time Discrete Diffusion Models [102.65769839899315]
We extend diffusion models to discrete variables by introducing a Markov jump process where the reverse process denoises via a continuous-time Markov chain.
We show that an unbiased estimator can be obtained via simple matching the conditional marginal distributions.
We demonstrate the effectiveness of the proposed method on a set of synthetic and real-world music and image benchmarks.
arXiv Detail & Related papers (2022-11-30T05:33:29Z) - Adversarial sampling of unknown and high-dimensional conditional
distributions [0.0]
In this paper the sampling method, as well as the inference of the underlying distribution, are handled with a data-driven method known as generative adversarial networks (GAN)
GAN trains two competing neural networks to produce a network that can effectively generate samples from the training set distribution.
It is shown that all the versions of the proposed algorithm effectively sample the target conditional distribution with minimal impact on the quality of the samples.
arXiv Detail & Related papers (2021-11-08T12:23:38Z) - Sampling from Arbitrary Functions via PSD Models [55.41644538483948]
We take a two-step approach by first modeling the probability distribution and then sampling from that model.
We show that these models can approximate a large class of densities concisely using few evaluations, and present a simple algorithm to effectively sample from these models.
arXiv Detail & Related papers (2021-10-20T12:25:22Z) - Stein Variational Inference for Discrete Distributions [70.19352762933259]
We propose a simple yet general framework that transforms discrete distributions to equivalent piecewise continuous distributions.
Our method outperforms traditional algorithms such as Gibbs sampling and discontinuous Hamiltonian Monte Carlo.
We demonstrate that our method provides a promising tool for learning ensembles of binarized neural network (BNN)
In addition, such transform can be straightforwardly employed in gradient-free kernelized Stein discrepancy to perform goodness-of-fit (GOF) test on discrete distributions.
arXiv Detail & Related papers (2020-03-01T22:45:41Z)
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.