The Annals of Probability

Minima in branching random walks

Louigi Addario-Berry and Bruce Reed

Source: Ann. Probab. Volume 37, Number 3 (2009), 1044-1079.

Abstract

Given a branching random walk, let Mn be the minimum position of any member of the nth generation. We calculate EMn to within O(1) and prove exponential tail bounds for P{|MnEMn|>x}, under quite general conditions on the branching random walk. In particular, together with work by Bramson [Z. Wahrsch. Verw. Gebiete 45 (1978) 89–108], our results fully characterize the possible behavior of EMn when the branching random walk has bounded branching and step size.

Primary Subjects: 60J80
Secondary Subjects: 60G50
Keywords: Branching random walks; branching processes; random trees

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Links and Identifiers

Permanent link to this document: http://projecteuclid.org/euclid.aop/1245434028
Digital Object Identifier: doi:10.1214/08-AOP428
Zentralblatt MATH identifier: 05587823
Mathematical Reviews number (MathSciNet): MR2537549

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