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We analyze in a closed form the learning dynamics of stochastic gradient descent (SGD) for a single-layer neural network classifying a high-dimensional Gaussian mixture where each cluster is assigned one of two labels. This problem provides…

Machine Learning · Computer Science 2022-03-28 Francesca Mignacco , Florent Krzakala , Pierfrancesco Urbani , Lenka Zdeborová

This work addresses the problem of simulating Gaussian random fields that are continuously indexed over a class of metric graphs, termed graphs with Euclidean edges, being more general and flexible than linear networks. We introduce three…

Statistics Theory · Mathematics 2024-04-29 Alfredo Alegría , Xavier Emery , Tobia Filosi , Emilio Porcu

Traditional MCMC algorithms are computationally intensive and do not scale well to large data. In particular, the Metropolis-Hastings (MH) algorithm requires passing over the entire dataset to evaluate the likelihood ratio in each…

Machine Learning · Statistics 2019-08-29 Tung-Yu Wu , Y. X. Rachel Wang , Wing H. Wong

Gaussian processes have been successful in both supervised and unsupervised machine learning tasks, but their computational complexity has constrained practical applications. We introduce a new approximation for large-scale Gaussian…

Machine Learning · Computer Science 2015-11-03 David A. Moore , Stuart J. Russell

The Metropolis-Hastings (MH) algorithm is one of the most widely used Markov Chain Monte Carlo schemes for generating samples from Bayesian posterior distributions. The algorithm is asymptotically exact, flexible and easy to implement.…

Methodology · Statistics 2026-03-10 Estevão Prado , Christopher Nemeth , Chris Sherlock

Structure formation in our Universe creates non-Gaussian random fields that will soon be observed over almost the entire sky by the Euclid satellite, the Vera-Rubin observatory, and the Square Kilometre Array. An unsolved problem is how to…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-10 Joey R. Braspenning , Elena Sellentin

Gaussian distributions are widely used in Bayesian variational inference to approximate intractable posterior densities, but the ability to accommodate skewness can improve approximation accuracy significantly, when data or prior…

Methodology · Statistics 2025-02-05 Linda S. L. Tan , Aoxiang Chen

The recently proposed non-Gaussian Mat\'{e}rn random field models, generated through Stochastic Partial differential equations (SPDEs), are extended by considering the class of Generalized Hyperbolic processes as noise forcings. The models…

Applications · Statistics 2013-07-25 David Bolin , Jonas Wallin

Two algorithms are proposed to simulate space-time Gaussian random fields with a covariance function belonging to an extended Gneiting class, the definition of which depends on a completely monotone function associated with the spatial…

Computation · Statistics 2019-12-05 Denis Allard , Xavier Emery , Céline Lacaux , Christian Lantuéjoul

We study maximum likelihood estimation for spatial generalized linear mixed models with Gaussian process approximations using a stochastic Newton-Raphson algorithm. We consider two Gaussian Process approximations in this context: spectral…

Methodology · Statistics 2026-05-19 Samuel I. Watson , Yixin Wang , Emanuele Giorgi

We compute the skewness of the matter distribution arising from non-linear evolution and from non-Gaussian initial perturbations. We apply our result to a very generic class of models with non-Gaussian initial conditions and we estimate…

Astrophysics · Physics 2009-12-30 Ruth Durrer , Roman Juszkiewicz , Martin Kunz , Jean-Philippe Uzan

While score-based generative models (SGMs) have achieved remarkable success in enormous image generation tasks, their mathematical foundations are still limited. In this paper, we analyze the approximation and generalization of SGMs in…

Machine Learning · Statistics 2024-02-26 Frank Cole , Yulong Lu

Gaussian processes (GPs) are distributions over functions, which provide a Bayesian nonparametric approach to regression and classification. In spite of their success, GPs have limited use in some applications, for example, in some cases a…

Machine Learning · Computer Science 2020-05-28 Alessio Benavoli , Dario Azzimonti , Dario Piga

This paper studies a risk minimization problem with decision dependent data distribution. The problem pertains to the performative prediction setting in which a trained model can affect the outcome estimated by the model. Such dependency…

Optimization and Control · Mathematics 2025-01-07 Qiang Li , Hoi-To Wai

A generator of spatio-temporal pseudo-random Gaussian fields that satisfy the "proportionality of scales" property (Tsyroulnikov, 2001) is presented. The generator is based on a third-order in time stochastic differential equation with a…

Data Analysis, Statistics and Probability · Physics 2018-05-15 Michael Tsyrulnikov , Dmitry Gayfulin

Metropolis Hastings nested sampling evolves a Markov chain, accepting new points along the chain according to a version of the Metropolis Hastings acceptance ratio, which has been modified to satisfy the nested sampling likelihood…

Computation · Statistics 2020-02-12 Kamran Javid

We propose a new model for regression and dependence analysis when addressing spatial data with possibly heavy tails and an asymmetric marginal distribution. We first propose a stationary process with $t$ marginals obtained through scale…

Statistics Theory · Mathematics 2019-12-20 M. Bevilacqua , C. Caamaño , R. B. Arellano Valle , V. Morales-Onñate

We introduce local expectation gradients which is a general purpose stochastic variational inference algorithm for constructing stochastic gradients through sampling from the variational distribution. This algorithm divides the problem of…

Machine Learning · Statistics 2015-03-06 Michalis K. Titsias

In the study of natural and artificial complex systems, responses that are not completely determined by the considered decision variables are commonly modelled probabilistically, resulting in response distributions varying across decision…

Methodology · Statistics 2021-10-07 Athénaïs Gautier , David Ginsbourger , Guillaume Pirot

We aim at analyzing geostatistical and areal data observed over irregularly shaped spatial domains and having a distribution within the exponential family. We propose a generalized additive model that allows to account for spatially-varying…

Methodology · Statistics 2016-04-22 Matthieu Wilhelm , Laura M. Sangalli