arXiv Machine Learning

Two-Sample Testing via Generative Processes

arXiv Machine Learning
Sep 3

Generative Diffusion Surrogates with Analytical Variance Schedule

The paper introduces a method for creating generative diffusion surrogates that use an analytically derived variance schedule based on the time derivative of known variance from macroscopic theory or empirical scaling. By enforcing this variance path, the model can capture non‑Gaussian structure in transport systems without requiring intermediate‑time physical data. The approach is validated on ballistic‑to‑diffusive transport in turbulent plasmas, accurately reproducing test‑particle distributions, laboratory‑measured variance, and simulated kurtosis evolution.

By Patrick Reichherzer, Gianluca Gregori, David N. Hosking, Subir Sarkar
arXiv Machine Learning
3d ago

Random-Bridges as Stochastic Transports for Generative Models

This paper introduces random-bridges—stochastic processes conditioned to hit target distributions at fixed times—as stochastic transports for generative modeling. Random-bridges can be Markovian or non‑Markovian, continuous or discontinuous, depending on the driving process, and the authors develop both theoretical foundations and practical training/simulation algorithms for Gaussian and Lévy (Gamma, Poisson, Stable‑1/2) bridges. Empirical results on the Gaussian case show that the proposed framework produces high‑quality samples with competitive Fréchet Inception Distance scores relative to popular denoising diffusion and flow‑matching methods.

By Stefano Goria, Levent A. Meng\"ut\"urk, Murat C. Meng\"ut\"urk, Berkan Sesen
arXiv Machine Learning
3d ago

Finite-Sample Sensitivity of Kernel Metrics for Generative Evaluation

The paper investigates how kernel-based metrics like KID and KAD perform as two‑sample tests on real embeddings of symbolic music, audio, and images. By applying mean shifts, isotropic contractions, and rotations to one sample, the authors find that the default kernels often fail to detect rotations at 780 samples per side, while they reliably detect mean shifts. Adjusting kernel bandwidths or using alternative kernels (e.g., narrower Gaussian, Laplace) restores sensitivity, and the authors recommend reporting the sample budget and detectable changes for any reported kernel distance.

By Tomasz Radzikowski, Mateusz Modrzejewski
arXiv AI
Jun 8

A Temporal Spatial Minimax Rate for Smoothly-Varying Distributions in Wasserstein Space

arXiv:2606. 07325v1 Announce Type: cross Abstract: We study the minimax rate of estimating a future value $\mu_{t_n+h}$ of a curve $t\mapsto\mu_t$ in the $2$-Wasserstein space $\mathcal{P}_2(\mathbb{R}^d)$ from finitely many noisy snapshots of its past, under an adiabatic bound $\|\nabla_t^k v\|\le\varepsilon$ on the $k$-th covariant derivative of the velocity field.

By Munsik Kim
arXiv Statistics ML
Oct 1

PTED: A multi-dimensional two-sample test for scientific inference and generative machine learning

The article introduces PTED, a Python implementation of a permutation test based on the Energy Distance for two-sample testing in multiple dimensions. PTED uses pairwise distances to compute a test statistic that works in high dimensions, on learned feature representations, and for any data type where a distance can be defined. The authors demonstrate that PTED scales linearly with dimensions and sample size while retaining strong discriminative power, and show it outperforms other multi‑dimensional tests in sensitivity.

By Connor Stone
arXiv Machine Learning
Oct 16

Vertical Sliced Wasserstein Distances for Meta-Measures

arXiv:2610. 20743v1 Announce Type: new Abstract: Many modern learning problems require comparing probability distributions whose individual observations are themselves probability measures, naturally giving rise to meta-measures in $\mathcal{P}(\mathcal{P}(\Omega))$.

By Elaheh Akbari, Ahmadreza Moradipari, Kyungtae Han, Hamed Pirsiavash, Yikun Bai, Rocio Diaz Martin, Soheil Kolouri
arXiv Machine Learning
Jul 20

Diffusion models recover accurate mixture weights despite score function insensitivity

arXiv:2607. 15485v1 Announce Type: new Abstract: Score-based generative models exhibit a puzzling behavior: they often appear to cover all modes of a target multimodal distribution and yet may fail to learn the correct relative mode amplitudes, which can be interpreted as mixture weights.

By Andrew Dennehy, Ramchandran Muthukumar, Rebecca Willett, Nisha Chandramoorthy