arXiv Machine Learning

Learning Transition Kernels of Jump-Diffusion Processes with Conditional Diffusion Models

The paper investigates learning transition kernels for time‑homogeneous jump‑diffusion processes using conditional diffusion models, aiming to generate new sample paths from high‑frequency discrete observations. It provides non‑asymptotic bounds on conditional score estimation error and KL divergence between true and generated path distributions. Experiments on synthetic data validate the theory and compare favorably to Gao et al. (2025), while real‑world applications demonstrate its utility for probabilistic forecasting.

arXiv Machine Learning
2d ago

Quantifying Error Propagation and Model Collapse in Diffusion Models

The paper investigates how repeatedly training score-based diffusion models on synthetic data can cause their outputs to drift from the target distribution. It provides theoretical upper and lower bounds on the divergence accumulated over successive training rounds, distinguishing regimes based on score estimation error and the fraction of fresh data used. Empirical experiments on synthetic data and images support the theoretical findings.

By Nail B. Khelifa, Richard E. Turner, Ramji Venkataramanan
arXiv Machine Learning
Sep 23

One-Step Generative Surrogate Models via Block-Triangular Joint Drifting

The paper introduces block‑triangular joint drifting, a method that applies a projected drift field to the joint distribution of consecutive states, enabling one‑step generative surrogate models for stochastic transition dynamics. This architecture preserves the current‑state marginal while directly sampling the conditional distribution of next states, allowing stochastic trajectories to be generated with a single model evaluation per time step. Experiments show that the approach achieves accurate marginal and trajectory‑dependent statistics with favorable accuracy‑cost tradeoffs compared to deterministic, diffusion, flow, and distillation‑based generative surrogates.

By Nicholas Geissler, Shreya Jha, Ricardo Baptista, Benjamin Peherstorfer
arXiv Machine Learning
Jul 14

Likelihood Matching for Diffusion Models

arXiv:2508. 03636v3 Announce Type: replace-cross Abstract: We propose a Likelihood Matching approach for training diffusion models by first establishing an equivalence between the likelihood of the target data distribution and a likelihood along the sample path of the reverse diffusion.

By Lei Qian, Wu Su, Yanqi Huang, Song Xi Chen
arXiv Statistics ML
Oct 12

Spatial Prediction with Guided Diffusion

Spatial prediction is a key task in analyses of spatially or spatio-temporally referenced data, typically handled with hierarchical models that combine a process model and a data model. The predictive distribution—conditional on observed data—is often intractable, but guided diffusion modeling from machine learning can sample from it when the likelihood is known and differentiable. The authors demonstrate this approach on Gaussian and non‑Gaussian processes, various data models (direct observations, aggregates, counts, censoring, area‑exceedance), validate against exact and MCMC results, and apply it to methane‑flux inversion over the UK and Ireland, showing accurate sampling, applicability to intractable MCMC cases, and good scalability with dimensionality.

By Andrew Zammit-Mangion, Lachlan Astfalck, Rapha\"el Huser, Christopher Nemeth, Henry B. Moss
arXiv Machine Learning
Jul 7

Non-Asymptotic Error Bounds for SMC with Biased Proposals: Application to Conditional Diffusion Sampling

arXiv:2607. 04780v1 Announce Type: cross Abstract: Sequential Monte Carlo (SMC) methods are a natural tool for post-hoc conditioning of pretrained generative models, but in many applications the mutation kernels used by the particle system are biased approximations of an ideal Feynman--Kac flow.

By Stanislas Strasman (SU, LPSM), Gabriel Victorino Cardoso (LPSM), Sylvain Le Corff (LPSM), Vincent Lemaire (LPSM), Antonio Ocello