## Bernoulli

• Bernoulli
• Volume 15, Number 4 (2009), 1305-1334.

### Small deviations of stable processes and entropy of the associated random operators

#### Abstract

We investigate the relation between the small deviation problem for a symmetric $α$-stable random vector in a Banach space and the metric entropy properties of the operator generating it. This generalizes former results due to Li and Linde and to Aurzada. It is shown that this problem is related to the study of the entropy numbers of a certain random operator. In some cases, an interesting gap appears between the entropy of the original operator and that of the random operator generated by it. This phenomenon is studied thoroughly for diagonal operators. Basic ingredients here are techniques related to random partitions of the integers. The main result concerning metric entropy and small deviations allows us to determine or provide new estimates for the small deviation rate for several symmetric $α$-stable random processes, including unbounded Riemann–Liouville processes, weighted Riemann–Liouville processes and the ($d$-dimensional)$α$-stable sheet.

#### Article information

Source
Bernoulli, Volume 15, Number 4 (2009), 1305-1334.

Dates
First available in Project Euclid: 8 January 2010

https://projecteuclid.org/euclid.bj/1262962237

Digital Object Identifier
doi:10.3150/09-BEJ212

Mathematical Reviews number (MathSciNet)
MR2597594

Zentralblatt MATH identifier
1214.60019

#### Citation

Aurzada, Frank; Lifshits, Mikhail; Linde, Werner. Small deviations of stable processes and entropy of the associated random operators. Bernoulli 15 (2009), no. 4, 1305--1334. doi:10.3150/09-BEJ212. https://projecteuclid.org/euclid.bj/1262962237

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