{ "id": "1910.07626", "version": "v1", "published": "2019-10-16T21:37:44.000Z", "updated": "2019-10-16T21:37:44.000Z", "title": "Diffusions on a space of interval partitions: Poisson-Dirichlet stationary distributions", "authors": [ "Noah Forman", "Soumik Pal", "Douglas Rizzolo", "Matthias Winkel" ], "comment": "50 pages, 8 figures. Following arXiv:1909.02584 [math.PR], this is the second in a sequence of three papers that will collectively supersede arXiv:1609.06706 [math.PR]", "categories": [ "math.PR" ], "abstract": "We introduce diffusions on a space of interval partitions of the unit interval that are stationary with the Poisson-Dirichlet laws with parameters $(\\alpha,0)$ and $(\\alpha,\\alpha)$. The construction has two steps. The first is a general construction of interval partition processes obtained previously, by decorating the jumps of a L\\'evy process with independent excursions. Here, we focus on the second step, which requires explicit transition kernels and what we call pseudo-stationarity. This allows us to study processes obtained from the original construction via scaling and time-change. In a sequel paper, we establish connections to diffusions on decreasing sequences introduced by Ethier and Kurtz (1981) and Petrov (2009). The latter diffusions are continuum limits of up-down Markov chains on Chinese restaurant processes. Our construction is also a step towards resolving longstanding conjectures by Feng and Sun on measure-valued Poisson-Dirichlet diffusions, and by Aldous on a continuum-tree-valued diffusion.", "revisions": [ { "version": "v1", "updated": "2019-10-16T21:37:44.000Z" } ], "analyses": { "subjects": [ "60J25", "60J60", "60J80", "60G18", "60G52", "60G55" ], "keywords": [ "poisson-dirichlet stationary distributions", "explicit transition kernels", "interval partition processes", "up-down markov chains", "chinese restaurant processes" ], "note": { "typesetting": "TeX", "pages": 50, "language": "en", "license": "arXiv", "status": "editable" } } }