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Sharp maximal inequality for martingales and stochastic integrals
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Adam Osekowski, University of Warsaw |
Abstract
Let $X=(X_t)_{tgeq 0}$ be a martingale and $H=(H_t)_{tgeq 0}$ be a predictable process taking values in $[-1,1]$. Let $Y$ denote the stochastic integral of $H$ with respect to $X$. We show that
$$ ||sup_{tgeq 0}Y_t||_1 leq beta_0 ||sup_{tgeq 0}|X_t|||_1,$$
where $beta_0=2,0856ldots$ is the best possible. Furthermore, if, in addition, $X$ is nonnegative, then
$$ ||sup_{tgeq 0}Y_t||_1 leq beta_0^+ ||sup_{tgeq 0}X_t||_1,$$
where $beta_0^+=frac{14}{9}$ is the best possible.
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Full text: PDF
Pages: 17-30
Published on: January 23, 2009
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Bibliography
-
K. Bichteler. Stochastic integration and $L^p$-theory of semimartingales .
Ann. Probab. 9 (1981), 49-89.
Math. Review 82g:60071
-
D. L. Burkholder. Boundary value problems and sharp inequalities for martingale transforms.
Ann. Probab. 12 (1984), 647-702.
Math. Review 86b:60080
-
D. L. Burkholder. Explorations in martingale theory and its applications.
Ecole d'Ete de Probabilités de Saint-Flour XIX---1989, 1--66, Lecture Notes in Math., 1464, Springer, Berlin, 1991.
Math. Review 92m:60037
-
D. L. Burkholder. Sharp norm comparison of martingale maximal functions and stochastic integrals.
Proceedings of the Norbert Wiener Centenary Congress, 1994 (East Lansing, MI, 1994), 343-358, Proc. Sympos. Appl. Math., 52, Amer. Math. Soc., Providence RI, 1997
Math. Review 98f:60103
-
A. Osekowski.
Sharp maximal inequality for stochastic integrals.
Proc. Amer. Math. Soc. 136 (2008), 2951-2958.
Math. Review number not available
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Electronic Communications in Probability. ISSN: 1083-589X |
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