{ "id": "1105.0632", "version": "v2", "published": "2011-05-03T16:47:15.000Z", "updated": "2012-05-22T08:19:28.000Z", "title": "Regularity of affine processes on general state spaces", "authors": [ "Martin Keller-Ressel", "Walter Schachermayer", "Josef Teichmann" ], "comment": "minor corrections", "categories": [ "math.PR" ], "abstract": "We consider a stochastically continuous, affine Markov process in the sense of Duffie, Filipovic and Schachermayer, with cadlag paths, on a general state space D, i.e. an arbitrary Borel subset of R^d. We show that such a process is always regular, meaning that its Fourier-Laplace transform is differentiable in time, with derivatives that are continuous in the transform variable. As a consequence, we show that generalized Riccati equations and Levy-Khintchine parameters for the process can be derived, as in the case of $D = R_+^m \\times R^n$ studied in Duffie, Filipovic and Schachermayer (2003). Moreover, we show that when the killing rate is zero, the affine process is a semi-martingale with absolutely continuous characteristics up to its time of explosion. Our results generalize the results of Keller-Ressel, Schachermayer and Teichmann (2011) for the state space $R_+^m \\times R^n$ and provide a new probabilistic approach to regularity.", "revisions": [ { "version": "v2", "updated": "2012-05-22T08:19:28.000Z" } ], "analyses": { "subjects": [ "60J25" ], "keywords": [ "general state space", "affine processes", "regularity", "schachermayer", "affine markov process" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2011arXiv1105.0632K" } } }