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For two vast families of mixture distributions and a given prior, we provide unified representations of posterior and predictive distributions. Model applications presented include bivariate mixtures of Gamma distributions labelled as…

Statistics Theory · Mathematics 2020-09-09 Aziz LMoudden , Éric Marchand

Finite mixture models, typically Gaussian mixtures, are well known and widely used as model-based clustering. In practical situations, there are many non-Gaussian data that are heavy-tailed and/or asymmetric. Normal inverse Gaussian (NIG)…

Machine Learning · Statistics 2020-09-15 Takashi Takekawa

This paper studies fundamental aspects of modelling data using multivariate Watson distributions. Although these distributions are natural for modelling axially symmetric data (i.e., unit vectors where $\pm \x$ are equivalent), for…

Computation · Statistics 2012-05-28 Suvrit Sra , Dmitrii Karp

In the framework of Bayesian model-based clustering based on a finite mixture of Gaussian distributions, we present a joint approach to estimate the number of mixture components and identify cluster-relevant variables simultaneously as well…

Methodology · Statistics 2016-06-23 Gertraud Malsiner-Walli , Sylvia Frühwirth-Schnatter , Bettina Grün

Probabilistic mixture models have been widely used for different machine learning and pattern recognition tasks such as clustering, dimensionality reduction, and classification. In this paper, we focus on trying to solve the most common…

Machine Learning · Computer Science 2020-04-08 Gustavo A Valencia-Zapata , Daniel Mejia , Gerhard Klimeck , Michael Zentner , Okan Ersoy

Traditional mediation models in both the frequentist and Bayesian frameworks typically assume normality of the error terms. Violations of this assumption can impair the estimation and hypothesis testing of the mediation effect in…

Methodology · Statistics 2025-09-04 Zongyu Li , Mark Steel , Zhiyong Zhang

In longitudinal studies, repeated measures are collected over time and hence they tend to be serially correlated. In this paper we consider an extension of skew-normal/independent linear mixed models introduced by Lachos et al. (2010),…

Methodology · Statistics 2021-01-19 Fernanda L. Schumacher , Victor H. Lachos , Larissa A. Matos

Count data is becoming more and more ubiquitous in a wide range of applications, with datasets growing both in size and in dimension. In this context, an increasing amount of work is dedicated to the construction of statistical models…

This paper addresses challenges in flexibly modeling multimodal data that lie on constrained spaces. Such data are commonly found in spatial applications, such as climatology and criminology, where measurements are restricted to a…

Computation · Statistics 2019-12-03 Putu Ayu Sudyanti , Vinayak Rao

Dirichlet process mixtures are flexible non-parametric models, particularly suited to density estimation and probabilistic clustering. In this work we study the posterior distribution induced by Dirichlet process mixtures as the sample size…

Statistics Theory · Mathematics 2022-11-29 Filippo Ascolani , Antonio Lijoi , Giovanni Rebaudo , Giacomo Zanella

Biological and social systems consist of myriad interacting units. The interactions can be represented in the form of a graph or network. Measurements of these graphs can reveal the underlying structure of these interactions, which provides…

Machine Learning · Statistics 2017-10-25 Norbert Binkiewicz , Joshua T. Vogelstein , Karl Rohe

An important and yet difficult problem in fitting multivariate mixture models is determining the mixture complexity. We develop theory and a unified framework for finding the nonparametric maximum likelihood estimator of a multivariate…

Statistics Theory · Mathematics 2007-06-13 Ramani S. Pilla , Francesco Bartolucci , Bruce G. Lindsay

Model-based clustering of moderate or large dimensional data is notoriously difficult. We propose a model for simultaneous dimensionality reduction and clustering by assuming a mixture model for a set of latent scores, which are then linked…

Methodology · Statistics 2024-06-04 Lorenzo Ghilotti , Mario Beraha , Alessandra Guglielmi

We develop a factor analysis for mixed continuous and binary observed variables. To this end, we utilized a recently developed multivariate probability distribution for mixed-type random variables, the Gaussian-Grassmann distribution. In…

Methodology · Statistics 2025-12-12 Takashi Arai

We investigate a clustering problem with data from a mixture of Gaussians that share a common but unknown, and potentially ill-conditioned, covariance matrix. We start by considering Gaussian mixtures with two equally-sized components and…

Machine Learning · Statistics 2021-11-30 Damek Davis , Mateo Díaz , Kaizheng Wang

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

High-dimensional data clustering has become and remains a challenging task for modern statistics and machine learning, with a wide range of applications. We consider in this work the powerful discriminative latent mixture model, and we…

Methodology · Statistics 2020-12-09 Nicolas Jouvin , Charles Bouveyron , Pierre Latouche

Finite mixture of Gaussian distributions provide a flexible semi-parametric methodology for density estimation when the variables under investigation have no boundaries. However, in practical applications variables may be partially bounded…

Methodology · Statistics 2019-12-30 Luca Scrucca

The mixture of Gaussian distributions, a soft version of k-means , is considered a state-of-the-art clustering algorithm. It is widely used in computer vision for selecting classes, e.g., color, texture, and shapes. In this algorithm, each…

Machine Learning · Statistics 2016-12-30 Mahajabin Rahman , Davi Geiger

Clustering large, mixed data is a central problem in data mining. Many approaches adopt the idea of k-means, and hence are sensitive to initialisation, detect only spherical clusters, and require a priori the unknown number of clusters. We…

Machine Learning · Statistics 2020-11-13 Joshua Tobin , Mimi Zhang
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