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In this paper we study the asymptotic properties of Bayesian multiple testing procedures for a large class of Gaussian scale mixture pri- ors. We study two types of multiple testing risks: a Bayesian risk proposed in Bogdan et al. (2011)…

Statistics Theory · Mathematics 2017-11-27 Jean-Bernard Salomond

We study regressions with multiple treatments and a set of controls that is flexible enough to purge omitted variable bias. We show that these regressions generally fail to estimate convex averages of heterogeneous treatment effects --…

Econometrics · Economics 2024-12-31 Paul Goldsmith-Pinkham , Peter Hull , Michal Kolesár

We investigate the frequentist guarantees of the variational sparse Gaussian process regression model. In the theoretical analysis, we focus on the variational approach with spectral features as inducing variables. We derive guarantees and…

Statistics Theory · Mathematics 2023-09-29 Dennis Nieman , Botond Szabo , Harry van Zanten

Convolutional sparse coding (CSC) can learn representative shift-invariant patterns from multiple kinds of data. However, existing CSC methods can only model noises from Gaussian distribution, which is restrictive and unrealistic. In this…

Machine Learning · Computer Science 2020-04-22 Yaqing Wang , James T. Kwok , Lionel M. Ni

We consider estimating the parameters of a Gaussian mixture density with a given number of components best representing a given set of weighted samples. We adopt a density interpretation of the samples by viewing them as a discrete Dirac…

Machine Learning · Statistics 2025-04-03 Daniel Frisch , Uwe D. Hanebeck

The inference of the causal relationship between a pair of observed variables is a fundamental problem in science, and most existing approaches are based on one single causal model. In practice, however, observations are often collected…

Machine Learning · Statistics 2018-11-13 Shoubo Hu , Zhitang Chen , Vahid Partovi Nia , Laiwan Chan , Yanhui Geng

Semi- and non-parametric mixture of regressions are a very useful flexible class of mixture of regressions in which some or all of the parameters are non-parametric functions of the covariates. These models are, however, based on the…

Methodology · Statistics 2026-01-13 Sphiwe B. Skhosana , Weixin Yao

Stochastic ordering among distributions has been considered in a variety of scenarios. Economic studies often involve research about the ordering of investment strategies or social welfare. However, as noted in the literature, stochastic…

Modelling spatio-temporal processes has become an important issue in current research. Since Gaussian processes are essentially determined by their second order structure, broad classes of covariance functions are of interest. Here, a new…

Statistics Theory · Mathematics 2011-02-28 Martin Schlather

We develop Bayesian nonparametric models for spatially indexed data of mixed type. Our work is motivated by challenges that occur in environmental epidemiology, where the usual presence of several confounding variables that exhibit complex…

Methodology · Statistics 2014-10-17 Georgios Papageorgiou , Sylvia Richardson , Nicky Best

This paper is devoted to the problem of sampling Gaussian fields in high dimension. Solutions exist for two specific structures of inverse covariance : sparse and circulant. The proposed approach is valid in a more general case and…

Computation · Statistics 2011-05-31 F. Orieux , O. Féron , J. -F. Giovannelli

Analysis of three-way data is becoming ever more prevalent in the literature, especially in the area of clustering and classification. Real data, including real three-way data, are often contaminated by potential outlying observations.…

We focus on Bayesian inverse problems with Gaussian likelihood, linear forward model, and priors that can be formulated as a Gaussian mixture. Such a mixture is expressed as an integral of Gaussian density functions weighted by a mixing…

Computation · Statistics 2024-08-30 Rafael Flock , Yiqiu Dong , Felipe Uribe , Olivier Zahm

Multivariate categorical data occur in many applications of machine learning. One of the main difficulties with these vectors of categorical variables is sparsity. The number of possible observations grows exponentially with vector length,…

Machine Learning · Statistics 2015-03-10 Yarin Gal , Yutian Chen , Zoubin Ghahramani

Mixtures of matrix Gaussian distributions provide a probabilistic framework for clustering continuous matrix-variate data, which are becoming increasingly prevalent in various fields. Despite its widespread adoption and successful…

Computation · Statistics 2023-07-21 Andrea Cappozzo , Alessandro Casa , Michael Fop

We consider the problem of detecting a general sparse mixture and obtain an explicit characterization of the phase transition under some conditions, generalizing the univariate results of Cai and Wu. Additionally, we provide a sufficient…

Statistics Theory · Mathematics 2021-05-27 Subhodh Kotekal

We describe the asymptotic behaviour of a filtration problem from a contaminated porous medium to a non-contaminated porous medium through thin vertical fissures of fixed height h>0, of random thinness of order {\epsilon} and which are…

Analysis of PDEs · Mathematics 2010-11-29 Alain Brillard , Mustapha El Jarroudi , M. El Merzguioui

A mixture of variance-gamma distributions is introduced and developed for model-based clustering and classification. The latest in a growing line of non-Gaussian mixture approaches to clustering and classification, the proposed mixture of…

Methodology · Statistics 2014-12-30 Sharon M. McNicholas , Paul D. McNicholas , Ryan P. Browne

This research creates a general class of "perturbation models" which are described by an underlying "null" model that accounts for most of the structure in data and a perturbation that accounts for possible small localized departures. The…

Statistics Theory · Mathematics 2007-06-13 Ramani S. Pilla , Catherine Loader

A mixture of multivariate contaminated normal distributions is developed for model-based clustering. In addition to the parameters of the classical normal mixture, our contaminated mixture has, for each cluster, a parameter controlling the…

Methodology · Statistics 2016-05-20 Antonio Punzo , Paul D. McNicholas