{ "id": "2412.13060", "version": "v1", "published": "2024-12-17T16:25:42.000Z", "updated": "2024-12-17T16:25:42.000Z", "title": "Exact simulation of the first-passage time of SDEs to time-dependent thresholds", "authors": [ "Devika Khurana", "Sascha Desmettre", "Evelyn Buckwar" ], "categories": [ "math.PR", "cs.NA", "math.NA" ], "abstract": "The first-passage time (FPT) is a fundamental concept in stochastic processes, representing the time it takes for a process to reach a specified threshold for the first time. Often, considering a time-dependent threshold is essential for accurately modeling stochastic processes, as it provides a more accurate and adaptable framework. In this paper, we extend an existing Exact simulation method developed for constant thresholds to handle time-dependent thresholds. Our proposed approach utilizes the FPT of Brownian motion and accepts it for the FPT of a given process with some probability, which is determined using Girsanov's transformation. This method eliminates the need to simulate entire paths over specific time intervals, avoids time-discretization errors, and directly simulates the first-passage time. We present results demonstrating the method's effectiveness, including the extension to time-dependent thresholds, an analysis of its time complexity, comparisons with existing methods through numerical examples, and its application to predicting spike times in a neuron.", "revisions": [ { "version": "v1", "updated": "2024-12-17T16:25:42.000Z" } ], "analyses": { "subjects": [ "37M05", "65C30", "60G05", "60H35", "68Q87", "92C20" ], "keywords": [ "first-passage time", "existing exact simulation method", "handle time-dependent thresholds", "avoids time-discretization errors", "simulate entire paths" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }