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Tangent sequences in Orlicz and rearrangement invariant spaces

Published online by Cambridge University Press:  24 October 2008

Paweł Hitczenko
Affiliation:
Department of Mathematics, Box 8205, North Carolina State University, Raleigh. NC 27695-8205, U.S.A
Stephen J. Montgomery-Smith
Affiliation:
Department of Mathematics, University of Missouri – Columbia, Columbia, MO 65211, U.S.A

Abstract

Let (fn) and (gn) be two sequences of random variables adapted to an increasing sequence of σ-algebras (ℱn) such that the conditional distributions of fn and gn given ℱn coincide. Suppose further that the sequence (gn) is conditionally independent. Then it is known that where the number C is a universal constant. The aim of this paper is to extend this result to certain classes of Orlicz and rearrangement invariant spaces. This paper includes fairly general techniques for obtaining rearrangement invariant inequalities from Orlicz norm inequalities.

Type
Research Article
Copyright
Copyright © Cambridge Philosophical Society 1996

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