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Related papers: Parsimonious Skew Mixture Models for Model-Based C…

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Finite mixture of skew distributions have emerged as an effective tool in modelling heterogeneous data with asymmetric features. With various proposals appearing rapidly in the recent years, which are similar but not identical, the…

Methodology · Statistics 2013-05-29 Sharon X. Lee , Geoffrey J. McLachlan

In this paper, we introduce a mixture of skew-t factor analyzers as well as a family of mixture models based thereon. The mixture of skew-t distributions model that we use arises as a limiting case of the mixture of generalized hyperbolic…

Methodology · Statistics 2014-05-05 Paula M. Murray , Ryan P. Browne , Paul D. McNicholas

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

This work introduces a refinement of the Parsimonious Model for fitting a Gaussian Mixture. The improvement is based on the consideration of clusters of the involved covariance matrices according to a criterion, such as sharing Principal…

Methodology · Statistics 2024-04-10 David Rodríguez-Vítores , Carlos Matrán

Finite Gaussian mixture models are widely used for model-based clustering of continuous data. Nevertheless, since the number of model parameters scales quadratically with the number of variables, these models can be easily…

Methodology · Statistics 2018-09-25 Michael Fop , Thomas Brendan Murphy , Luca Scrucca

Families of mixtures of multivariate power exponential (MPE) distributions have been previously introduced and shown to be competitive for cluster analysis in comparison to other elliptical mixtures including mixtures of Gaussian…

Computation · Statistics 2023-01-24 Utkarsh J. Dang , Michael P. B. Gallaugher , Ryan P. Browne , Paul D. McNicholas

Because of its mathematical tractability, the Gaussian mixture model holds a special place in the literature for clustering and classification. For all its benefits, however, the Gaussian mixture model poses problems when the data is skewed…

Applications · Statistics 2020-11-19 Michael P. B. Gallaugher , Paul D. McNicholas , Volodymyr Melnykov , Xuwen Zhu

A mixture of common skew-t factor analyzers model is introduced for model-based clustering of high-dimensional data. By assuming common component factor loadings, this model allows clustering to be performed in the presence of a large…

Methodology · Statistics 2014-05-05 Paula M. Murray , Paul D. McNicholas , Ryan P. Browne

A family of parsimonious shifted asymmetric Laplace mixture models is introduced. We extend the mixture of factor analyzers model to the shifted asymmetric Laplace distribution. Imposing constraints on the constitute parts of the resulting…

Methodology · Statistics 2013-11-05 Brian C. Franczak , Paul D. McNicholas , Ryan P. Browne , Paula M. Murray

In many situations we are interested in modeling real data where the response distribution, even conditionally on the covariates, presents asymmetry and/or heavy/light tails. In these situations, it is more suitable to consider models based…

Methodology · Statistics 2024-06-06 João Victor B. de Freitas , Caio L. N. Azevedo

Gaussian mixture models (GMMs) are ubiquitous in statistical learning, particularly for unsupervised problems. While full GMMs suffer from the overparameterization of their covariance matrices in high-dimensional spaces, spherical GMMs…

Machine Learning · Statistics 2025-11-10 Tom Szwagier , Pierre-Alexandre Mattei , Charles Bouveyron , Xavier Pennec

Non-Gaussian mixture models are gaining increasing attention for mixture model-based clustering particularly when dealing with data that exhibit features such as skewness and heavy tails. Here, such a mixture distribution is presented,…

Computation · Statistics 2020-05-07 Yuan Fang , Dimitris Karlis , Sanjeena Subedi

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

Robust clustering from incomplete data is an important topic because, in many practical situations, real data sets are heavy-tailed, asymmetric, and/or have arbitrary patterns of missing observations. Flexible methods and algorithms for…

Methodology · Statistics 2018-11-13 Yuhong Wei , Yang Tang , Paul D. McNicholas

A family of parsimonious Gaussian cluster-weighted models is presented. This family concerns a multivariate extension to cluster-weighted modelling that can account for correlations between multivariate responses. Parsimony is attained by…

Much work has been done in the area of the cluster weighted model (CWM), which extends the finite mixture of regression model to include modelling of the covariates. Although many types of distributions have been considered for both the…

Gaussian mixture models with eigen-decomposed covariance structures make up the most popular family of mixture models for clustering and classification, i.e., the Gaussian parsimonious clustering models (GPCM). Although the GPCM family has…

Methodology · Statistics 2014-05-05 Antonio Punzo , Ryan P. Browne , Paul D. McNicholas

Handling missing data is a major challenge in model-based clustering, especially when the data exhibit skewness and heavy tails. We address this by extending the finite mixture of scale mixtures of multivariate skew-normal (FMSMSN) family…

Methodology · Statistics 2025-07-29 Jason Pillay , Cristina Tortora , Antonio Punzo , Andriette Bekker

A new maximum approximate likelihood (ML) estimation algorithm for the mixture of Kent distribution is proposed. The new algorithm is constructed via the BSLM (block successive lower-bound maximization) framework and incorporates manifold…

Computation · Statistics 2017-09-15 Hien D. Nguyen

Skew normal mixture models provide a more flexible framework than the popular normal mixtures for modelling heterogeneous data with asymmetric behaviors. Due to the unboundedness of likelihood function and the divergency of shape…

Methodology · Statistics 2016-08-05 Libin Jin , Wangli Xu , Liping Zhu , Lixing Zhu
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