A Numerical Schemefor the Probability Density of the First Hitting Time for Some Random Processes

Departing from a general stochastic model for a moving boundary problem, we consider the density function of probability for the first passing time. It is well known that the distribution of this random variable satisfies a problem ruled by an advection–diffusion system for which very few solutions...

Full description

Bibliographic Details
Main Author: Jorge E. Macías-Díaz
Format: Article
Language:English
Published: MDPI AG 2020-11-01
Series:Symmetry
Subjects:
Online Access:https://www.mdpi.com/2073-8994/12/11/1907
_version_ 1797547278516355072
author Jorge E. Macías-Díaz
author_facet Jorge E. Macías-Díaz
author_sort Jorge E. Macías-Díaz
collection DOAJ
description Departing from a general stochastic model for a moving boundary problem, we consider the density function of probability for the first passing time. It is well known that the distribution of this random variable satisfies a problem ruled by an advection–diffusion system for which very few solutions are known in exact form. The model considers also a deterministic source, and the coefficients of this equation are functions with sufficient regularity. A numerical scheme is designed to estimate the solutions of the initial-boundary-value problem. We prove rigorously that the numerical model is capable of preserving the main characteristics of the solutions of the stochastic model, that is, positivity, boundedness and monotonicity. The scheme has spatial symmetry, and it is theoretically analyzed for consistency, stability and convergence. Some numerical simulations are carried out in this work to assess the capability of the discrete model to preserve the main structural features of the solutions of the model. Moreover, a numerical study confirms the efficiency of the scheme, in agreement with the mathematical results obtained in this work.
first_indexed 2024-03-10T14:42:03Z
format Article
id doaj.art-80dd6f727cf84f0cb1c5fe60d1644db6
institution Directory Open Access Journal
issn 2073-8994
language English
last_indexed 2024-03-10T14:42:03Z
publishDate 2020-11-01
publisher MDPI AG
record_format Article
series Symmetry
spelling doaj.art-80dd6f727cf84f0cb1c5fe60d1644db62023-11-20T21:41:43ZengMDPI AGSymmetry2073-89942020-11-011211190710.3390/sym12111907A Numerical Schemefor the Probability Density of the First Hitting Time for Some Random ProcessesJorge E. Macías-Díaz0Department of Mathematics, School of Digital Technologies, Tallinn University, 10120 Tallinn, EstoniaDeparting from a general stochastic model for a moving boundary problem, we consider the density function of probability for the first passing time. It is well known that the distribution of this random variable satisfies a problem ruled by an advection–diffusion system for which very few solutions are known in exact form. The model considers also a deterministic source, and the coefficients of this equation are functions with sufficient regularity. A numerical scheme is designed to estimate the solutions of the initial-boundary-value problem. We prove rigorously that the numerical model is capable of preserving the main characteristics of the solutions of the stochastic model, that is, positivity, boundedness and monotonicity. The scheme has spatial symmetry, and it is theoretically analyzed for consistency, stability and convergence. Some numerical simulations are carried out in this work to assess the capability of the discrete model to preserve the main structural features of the solutions of the model. Moreover, a numerical study confirms the efficiency of the scheme, in agreement with the mathematical results obtained in this work.https://www.mdpi.com/2073-8994/12/11/1907moving boundary problemprobability distribution function of the first hitting timeadvection–diffusion problemimplicit finite-difference modelspatially symmetric discrete modeltheoretical analysis
spellingShingle Jorge E. Macías-Díaz
A Numerical Schemefor the Probability Density of the First Hitting Time for Some Random Processes
Symmetry
moving boundary problem
probability distribution function of the first hitting time
advection–diffusion problem
implicit finite-difference model
spatially symmetric discrete model
theoretical analysis
title A Numerical Schemefor the Probability Density of the First Hitting Time for Some Random Processes
title_full A Numerical Schemefor the Probability Density of the First Hitting Time for Some Random Processes
title_fullStr A Numerical Schemefor the Probability Density of the First Hitting Time for Some Random Processes
title_full_unstemmed A Numerical Schemefor the Probability Density of the First Hitting Time for Some Random Processes
title_short A Numerical Schemefor the Probability Density of the First Hitting Time for Some Random Processes
title_sort numerical schemefor the probability density of the first hitting time for some random processes
topic moving boundary problem
probability distribution function of the first hitting time
advection–diffusion problem
implicit finite-difference model
spatially symmetric discrete model
theoretical analysis
url https://www.mdpi.com/2073-8994/12/11/1907
work_keys_str_mv AT jorgeemaciasdiaz anumericalschemefortheprobabilitydensityofthefirsthittingtimeforsomerandomprocesses
AT jorgeemaciasdiaz numericalschemefortheprobabilitydensityofthefirsthittingtimeforsomerandomprocesses