Skewness-Kurtosis Model-Based Projection Pursuit with Application to Summarizing Gene Expression Data

Non-normality is a usual fact when dealing with gene expression data. Thus, flexible models are needed in order to account for the underlying asymmetry and heavy tails of multivariate gene expression measures. This paper addresses the issue by exploring the projection pursuit problem under a flexibl...

Full description

Bibliographic Details
Main Authors: Jorge M. Arevalillo, Hilario Navarro
Format: Article
Language:English
Published: MDPI AG 2021-04-01
Series:Mathematics
Subjects:
Online Access:https://www.mdpi.com/2227-7390/9/9/954
_version_ 1797536443517632512
author Jorge M. Arevalillo
Hilario Navarro
author_facet Jorge M. Arevalillo
Hilario Navarro
author_sort Jorge M. Arevalillo
collection DOAJ
description Non-normality is a usual fact when dealing with gene expression data. Thus, flexible models are needed in order to account for the underlying asymmetry and heavy tails of multivariate gene expression measures. This paper addresses the issue by exploring the projection pursuit problem under a flexible framework where the underlying model is assumed to follow a multivariate skew-t distribution. Under this assumption, projection pursuit with skewness and kurtosis indices is addressed as a natural approach for data reduction. The work examines its properties giving some theoretical insights and delving into the computational side in regards to the application to real gene expression data. The results of the theory are illustrated by means of a simulation study; the outputs of the simulation are used in combination with the theoretical insights to shed light on the usefulness of skewness-kurtosis projection pursuit for summarizing multivariate gene expression data. The application to gene expression measures of patients diagnosed with triple-negative breast cancer gives promising findings that may contribute to explain the heterogeneity of this type of tumors.
first_indexed 2024-03-10T12:00:46Z
format Article
id doaj.art-4d7f7867cd254200bd1cf538fc4429d2
institution Directory Open Access Journal
issn 2227-7390
language English
last_indexed 2024-03-10T12:00:46Z
publishDate 2021-04-01
publisher MDPI AG
record_format Article
series Mathematics
spelling doaj.art-4d7f7867cd254200bd1cf538fc4429d22023-11-21T16:59:29ZengMDPI AGMathematics2227-73902021-04-019995410.3390/math9090954Skewness-Kurtosis Model-Based Projection Pursuit with Application to Summarizing Gene Expression DataJorge M. Arevalillo0Hilario Navarro1Department of Statistics and Operational Research, University Nacional Educación a Distancia (UNED), 28040 Madrid, SpainDepartment of Statistics and Operational Research, University Nacional Educación a Distancia (UNED), 28040 Madrid, SpainNon-normality is a usual fact when dealing with gene expression data. Thus, flexible models are needed in order to account for the underlying asymmetry and heavy tails of multivariate gene expression measures. This paper addresses the issue by exploring the projection pursuit problem under a flexible framework where the underlying model is assumed to follow a multivariate skew-t distribution. Under this assumption, projection pursuit with skewness and kurtosis indices is addressed as a natural approach for data reduction. The work examines its properties giving some theoretical insights and delving into the computational side in regards to the application to real gene expression data. The results of the theory are illustrated by means of a simulation study; the outputs of the simulation are used in combination with the theoretical insights to shed light on the usefulness of skewness-kurtosis projection pursuit for summarizing multivariate gene expression data. The application to gene expression measures of patients diagnosed with triple-negative breast cancer gives promising findings that may contribute to explain the heterogeneity of this type of tumors.https://www.mdpi.com/2227-7390/9/9/954skewnesskurtosisskew-t distributionprojection pursuitgene expression data
spellingShingle Jorge M. Arevalillo
Hilario Navarro
Skewness-Kurtosis Model-Based Projection Pursuit with Application to Summarizing Gene Expression Data
Mathematics
skewness
kurtosis
skew-t distribution
projection pursuit
gene expression data
title Skewness-Kurtosis Model-Based Projection Pursuit with Application to Summarizing Gene Expression Data
title_full Skewness-Kurtosis Model-Based Projection Pursuit with Application to Summarizing Gene Expression Data
title_fullStr Skewness-Kurtosis Model-Based Projection Pursuit with Application to Summarizing Gene Expression Data
title_full_unstemmed Skewness-Kurtosis Model-Based Projection Pursuit with Application to Summarizing Gene Expression Data
title_short Skewness-Kurtosis Model-Based Projection Pursuit with Application to Summarizing Gene Expression Data
title_sort skewness kurtosis model based projection pursuit with application to summarizing gene expression data
topic skewness
kurtosis
skew-t distribution
projection pursuit
gene expression data
url https://www.mdpi.com/2227-7390/9/9/954
work_keys_str_mv AT jorgemarevalillo skewnesskurtosismodelbasedprojectionpursuitwithapplicationtosummarizinggeneexpressiondata
AT hilarionavarro skewnesskurtosismodelbasedprojectionpursuitwithapplicationtosummarizinggeneexpressiondata