{ "id": "0904.3468", "version": "v1", "published": "2009-04-22T14:30:58.000Z", "updated": "2009-04-22T14:30:58.000Z", "title": "Quasi-stationary distributions for structured birth and death processes with mutations", "authors": [ "Pierre Collet", "Servet Martinez", "Sylvie Méléard", "Jaime San Martin" ], "comment": "39 pages", "categories": [ "math.PR" ], "abstract": "We study the probabilistic evolution of a birth and death continuous time measure-valued process with mutations and ecological interactions. The individuals are characterized by (phenotypic) traits that take values in a compact metric space. Each individual can die or generate a new individual. The birth and death rates may depend on the environment through the action of the whole population. The offspring can have the same trait or can mutate to a randomly distributed trait. We assume that the population will be extinct almost surely. Our goal is the study, in this infinite dimensional framework, of quasi-stationary distributions when the process is conditioned on non-extinction. We firstly show in this general setting, the existence of quasi-stationary distributions. This result is based on an abstract theorem proving the existence of finite eigenmeasures for some positive operators. We then consider a population with constant birth and death rates per individual and prove that there exists a unique quasi-stationary distribution with maximal exponential decay rate. The proof of uniqueness is based on an absolute continuity property with respect to a reference measure.", "revisions": [ { "version": "v1", "updated": "2009-04-22T14:30:58.000Z" } ], "analyses": { "subjects": [ "92D25", "60K35", "60J70", "60J80" ], "keywords": [ "quasi-stationary distribution", "death processes", "structured birth", "individual", "death rates" ], "note": { "typesetting": "TeX", "pages": 39, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2009arXiv0904.3468C" } } }