Extinction in lower Hessenberg branching processes with countably many types

Autor: Sophie Hautphenne, Peter Braunsteins
Jazyk: angličtina
Rok vydání: 2019
Předmět:
Zdroj: Ann. Appl. Probab. 29, no. 5 (2019), 2782-2818
ISSN: 2782-2818
Popis: We consider a class of branching processes with countably many types which we refer to as Lower Hessenberg branching processes. These are multitype Galton–Watson processes with typeset $\mathcal{X}=\{0,1,2,\ldots\}$, in which individuals of type $i$ may give birth to offspring of type $j\leq i+1$ only. For this class of processes, we study the set $S$ of fixed points of the progeny generating function. In particular, we highlight the existence of a continuum of fixed points whose minimum is the global extinction probability vector $\boldsymbol{q}$ and whose maximum is the partial extinction probability vector $\boldsymbol{\tilde{q}}$. In the case where $\boldsymbol{\tilde{q}}=\boldsymbol{1}$, we derive a global extinction criterion which holds under second moment conditions, and when $\boldsymbol{\tilde{q}}
Databáze: OpenAIRE