{ "id": "2010.08284", "version": "v1", "published": "2020-10-16T10:21:17.000Z", "updated": "2020-10-16T10:21:17.000Z", "title": "On non-negative solutions of SDDEs with an application to CARMA processes", "authors": [ "Mikkel Slot Nielsen", "Victor Rohde" ], "categories": [ "math.PR" ], "abstract": "This note provides a simple sufficient condition ensuring that solutions of stochastic delay differential equations (SDDEs) driven by subordinators are non-negative. While, to the best of our knowledge, no simple non-negativity conditions are available in the context of SDDEs, we compare our result to the literature within the subclass of invertible continuous-time ARMA (CARMA) processes. In particular, we analyze why our condition cannot be necessary for CARMA($p,q$) processes when $p=2$, and we show that there are various situations where our condition applies while existing results do not as soon as $p\\geq 3$. Finally, we extend the result to a multidimensional setting.", "revisions": [ { "version": "v1", "updated": "2020-10-16T10:21:17.000Z" } ], "analyses": { "subjects": [ "60G10", "60G17", "60H05", "60H10" ], "keywords": [ "carma processes", "non-negative solutions", "application", "stochastic delay differential equations", "simple non-negativity conditions" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }