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Non-Comparability with respect to the convex transform order with applications

Published online by Cambridge University Press:  23 November 2020

Idir Arab*
Affiliation:
University of Coimbra
Milto Hadjikyriakou*
Affiliation:
University of Central Lancashire
Paulo Eduardo Oliveira*
Affiliation:
University of Coimbra
*
*Postal address: CMUC, Department of Mathematics, University of Coimbra, PO Box 3008, EC Santa Cruz, Coimbra, Portugal. Email address: paulo@mat.uc.pt
**Postal address: School of Sciences, 12–14 University Avenue, Pyla, 7080 Larnaka, Cyprus.
*Postal address: CMUC, Department of Mathematics, University of Coimbra, PO Box 3008, EC Santa Cruz, Coimbra, Portugal. Email address: paulo@mat.uc.pt

Abstract

In the literature of stochastic orders, one rarely finds results characterizing non-comparability of random variables. We prove simple tools implying the non-comparability with respect to the convex transform order. The criteria are used, among other applications, to provide a negative answer for a conjecture about comparability in a much broader scope than its initial statement.

Type
Research Papers
Copyright
© Applied Probability Trust 2020

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