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MULTIVARIATE DISPERSION ORDER AND THE NOTION OF COPULA APPLIED TO THE MULTIVARIATE t-DISTRIBUTION

Published online by Cambridge University Press:  22 June 2005

J. P. Arias-Nicolás
Affiliation:
Department of Mathematics, University of Extremadura, Extremadura, Spain, E-mail: jparias@unex.es
J. M. Fernández-Ponce
Affiliation:
Department of Statistics, University of Sevilla, 41013 Sevilla, Spain, E-mail: ferpon@us.es; calvo@us.es
P. Luque-Calvo
Affiliation:
Department of Statistics, University of Sevilla, 41013 Sevilla, Spain, E-mail: ferpon@us.es; calvo@us.es
A. Suárez-Llorens
Affiliation:
Department of Statistics, University of Cádiz, 11002 Cádiz, Spain, E-mail: alfonso.suarez@uca.es

Abstract

We study the concept of multivariate dispersion order, defined as the existence of an expansion function that maps a random vector to another one, for multivariate distributions with the same dependence structure. As a particular case, we can order the multivariate t-distribution family in dispersion sense. Finally, we use these results in the problem of detection and characterization of influential observations in regression analysis. This problem can often be used to compare two multivariate t-distributions.

Type
Research Article
Copyright
© 2005 Cambridge University Press

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References

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