{ "id": "2001.04523", "version": "v1", "published": "2020-01-13T20:15:37.000Z", "updated": "2020-01-13T20:15:37.000Z", "title": "Quasi-Limiting Behavior of Drifted Brownian Motion", "authors": [ "SangJoon Lee", "Iddo Ben-Ari" ], "categories": [ "math.PR" ], "abstract": "A Quasi-Stationary Distribution (QSD)for a Markov process with an almost surely hit absorbing state is a time-invariant initial distribution for the process conditioned on not being absorbed by any given time. An initial distribution for the process is in the domain of attraction of some QSD $\\nu$ if the distribution of the process a time $t$, conditioned not to be absorbed by time $t$ converges to $\\nu$. In this work study mostly Brownian motion with constant drift on the half line $[0,\\infty)$ absorbed at $0$. Previous work by Martinez et al. identifies all QSDs and provides a nearly complete characterization for their domain of attraction. Specifically, it was shown that if the distribution a well-defined exponential tail (including the case of lighter than any exponential tail), then it is in the domain of attraction of a QSD determined by the exponent. In this work we 1. Obtain a new approach to existing results, explaining the direct relation between a QSD and an initial distribution in its domain of attraction. 2. Study the behavior under a wide class of initial distributions whose tail is heavier than exponential, and obtain no-trivial limits under appropriate scaling.", "revisions": [ { "version": "v1", "updated": "2020-01-13T20:15:37.000Z" } ], "analyses": { "keywords": [ "drifted brownian motion", "quasi-limiting behavior", "exponential tail", "attraction", "time-invariant initial distribution" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }