Electronic Communications in Probability

Weighted moments for Mandelbrot's martingales

Abstract

Let $(Y_n)_{n\ge0}$ be a Mandelbrot's martingale defined as sums of products of random weights indexed by nodes of a Galton-Watson tree, and let $Y$ be its limit.  We show a necessary and sufficient condition for the existence of weighted moments of $Y$ of the forms $\mathbb{E}Y^{\alpha}\ell(Y)$, where $\alpha>1$ and $\ell$ is a positive function slowly varying at $\infty$. We also show a sufficient condition in the case of $\alpha=1$. Our results complete those of Alsmeyer and Kuhlbusch (2010) for weighted branching processes by removing their extra conditions on $\ell$.

Article information

Source
Electron. Commun. Probab., Volume 20 (2015), paper no. 85, 12 pp.

Dates
Accepted: 11 November 2015
First available in Project Euclid: 7 June 2016

https://projecteuclid.org/euclid.ecp/1465321012

Digital Object Identifier
doi:10.1214/ECP.v20-4443

Mathematical Reviews number (MathSciNet)
MR3434202

Zentralblatt MATH identifier
1335.60062

Rights

Citation

Liang, Xingang; Liu, Quansheng. Weighted moments for Mandelbrot's martingales. Electron. Commun. Probab. 20 (2015), paper no. 85, 12 pp. doi:10.1214/ECP.v20-4443. https://projecteuclid.org/euclid.ecp/1465321012

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