Let $$ be the $$-functional of a stable Lévy process starting from one and killed when crossing zero. We observe that $$ can be represented as the independent quotient of two infinite products of renormalized Beta random variables. The proof relies on Markovian time change, the Lamperti transformation, and an explicit computation performed in [38] on perpetuities of hypergeometric Lévy processes. This representation allows us to retrieve several factorizations previously shown by various authors, and also to derive new ones. We emphasize the connections between $$ and more standard positive random variables. We also investigate the law of Riemannian integrals of stable subordinators. Finally, we derive several distributional properties of $$ related to infinite divisibility, self-decomposability, and the generalized Gamma convolution.
Accepté le :
DOI : 10.1051/ps/2018028
Keywords: Beta random variable, exponential functional, homogeneous functional, infinite divisibility, stable Lévy process, time-change
Letemplier, Julien 1 ; Simon, Thomas 1
@article{PS_2019__23__82_0,
author = {Letemplier, Julien and Simon, Thomas},
title = {On the law of homogeneous stable functionals},
journal = {ESAIM: Probability and Statistics},
pages = {82--111},
year = {2019},
publisher = {EDP Sciences},
volume = {23},
doi = {10.1051/ps/2018028},
mrnumber = {3922819},
zbl = {1411.60070},
language = {en},
url = {https://www.numdam.org/articles/10.1051/ps/2018028/}
}
TY - JOUR AU - Letemplier, Julien AU - Simon, Thomas TI - On the law of homogeneous stable functionals JO - ESAIM: Probability and Statistics PY - 2019 SP - 82 EP - 111 VL - 23 PB - EDP Sciences UR - https://www.numdam.org/articles/10.1051/ps/2018028/ DO - 10.1051/ps/2018028 LA - en ID - PS_2019__23__82_0 ER -
Letemplier, Julien; Simon, Thomas. On the law of homogeneous stable functionals. ESAIM: Probability and Statistics, Tome 23 (2019), pp. 82-111. doi: 10.1051/ps/2018028
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