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COMPARISON OF WEAK AND STRONG MOMENTS FOR VECTORS WITH INDEPENDENT COORDINATES

Published online by Cambridge University Press:  14 February 2018

Rafał Latała
Affiliation:
Institute of Mathematics, University of Warsaw, Banacha 2, 02–097 Warsaw, Poland email [email protected]
Marta Strzelecka
Affiliation:
Institute of Mathematics, University of Warsaw, Banacha 2, 02–097 Warsaw, Poland email [email protected]
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Abstract

We show that for $p\geqslant 1$, the $p$th moment of suprema of linear combinations of independent centered random variables are comparable with the sum of the first moment and the weak $p$th moment provided that $2q$th and $q$th integral moments of these variables are comparable for all $q\geqslant 2$. The latest condition turns out to be necessary in the independent and identically distributed case.

Type
Research Article
Copyright
Copyright © University College London 2018 

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