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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

Matrix-variate distributions can intuitively model the dependence structure of matrix-valued observations that arise in applications with multivariate time series, spatio-temporal or repeated measures. This paper develops an…

Methodology · Statistics 2019-12-24 Geoffrey Z. Thompson , Ranjan Maitra , William Q. Meeker , Ashraf Bastawros

In cluster analysis, it can be useful to interpret the partition built from the data in the light of external categorical variables which were not directly involved to cluster the data. An approach is proposed in the model-based clustering…

The use of a finite mixture of normal distributions in model-based clustering allows to capture non-Gaussian data clusters. However, identifying the clusters from the normal components is challenging and in general either achieved by…

Methodology · Statistics 2016-06-21 Gertraud Malsiner-Walli , Sylvia Frühwirth-Schnatter , Bettina Grün

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 a wide variety of situations, anomalies in the behaviour of a complex system, whose health is monitored through the observation of a random vector X = (X1,. .. , X d) valued in R d , correspond to the simultaneous occurrence of extreme…

Methodology · Statistics 2019-07-18 Maël Chiapino , Stéphan Clémençon , Vincent Feuillard , Anne Sabourin

Discrete mixture models provide a well-known basis for effective clustering algorithms, although technical challenges have limited their scope. In the context of gene-expression data analysis, a model is presented that mixes over a finite…

Methodology · Statistics 2012-11-12 Michael A. Newton , Lisa M. Chung

Identifying relationships between molecular variations and their clinical presentations has been challenged by the heterogeneous causes of a disease. It is imperative to unveil the relationship between the high dimensional molecular…

Methodology · Statistics 2021-09-02 Wennan Chang , Changlin Wan , Yong Zang , Chi Zhang , Sha Cao

Early and accurate detection of anomalies in time series data is critical, given the significant risks associated with false or missed detections. While MLP-based mixer models have shown promise in time series analysis, they lack a…

Machine Learning · Computer Science 2025-06-03 Md Mahmuddun Nabi Murad , Yasin Yilmaz

A dynamic factor model with a mixture distribution of the loadings is introduced and studied for multivariate, possibly high-dimensional time series. The correlation matrix of the model exhibits a block structure, reminiscent of correlation…

Methodology · Statistics 2023-07-20 Shankar Bhamidi , Dhruv Patel , Vladas Pipiras , Guorong Wu

Clustered data is ubiquitous in a variety of scientific fields. In this paper, we propose a flexible and interpretable modeling approach, called grouped heterogenous mixture modeling, for clustered data, which models cluster-wise…

Methodology · Statistics 2020-02-10 Shonosuke Sugasawa

Biclustering is used for simultaneous clustering of the observations and variables when there is no group structure known \textit{a priori}. It is being increasingly used in bioinformatics, text analytics, etc. Previously, biclustering has…

Methodology · Statistics 2020-09-14 Wangshu Tu , Sanjeena Subedi

We describe and analyze a broad class of mixture models for real-valued multivariate data in which the probability density of observations within each component of the model is represented as an arbitrary combination of basis functions.…

Methodology · Statistics 2025-02-28 M. E. J. Newman

We explore the possibility of discovering extreme voting patterns in the U.S. Congressional voting records by drawing ideas from the mixture of contaminated normal distributions. A mixture of latent trait models via contaminated normal…

Methodology · Statistics 2018-05-14 Yang Tang , Paul D. McNicholas , Antonio Punzo

Many machine learning problems can be characterized by mutual contamination models. In these problems, one observes several random samples from different convex combinations of a set of unknown base distributions and the goal is to infer…

Machine Learning · Statistics 2019-04-12 Julian Katz-Samuels , Gilles Blanchard , Clayton Scott

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

The contaminated Gaussian distribution represents a simple heavy-tailed elliptical generalization of the Gaussian distribution; unlike the often-considered t-distribution, it also allows for automatic detection of mild outlying or "bad"…

Methodology · Statistics 2019-08-30 Antonio Punzo , Martin Blostein , Paul D. McNicholas

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

Robust clustering of high-dimensional data is an important topic because clusters in real datasets are often heavy-tailed and/or asymmetric. Traditional approaches to model-based clustering often fail for high dimensional data, e.g., due to…

Methodology · Statistics 2024-06-07 Alexa A. Sochaniwsky , Michael P. B. Gallaugher , Yang Tang , Paul D. McNicholas

Model-based unsupervised learning, as any learning task, stalls as soon as missing data occurs. This is even more true when the missing data are informative, or said missing not at random (MNAR). In this paper, we propose model-based…