Electron. J. Differential Equations, Vol. 2019 (2019), No. 85, pp. 1-40.

Approximate solutions of randomized non-autonomous complete linear differential equations via probability density functions

Julia Calatayud, Juan Carlos Cortes, Marc Jornet

Abstract:
Solving a random differential equation means to obtain an exact or approximate expression for the solution stochastic process, and to compute its statistical properties, mainly the mean and the variance functions. However, a major challenge is the computation of the probability density function of the solution. In this article we construct reliable approximations of the probability density function to the randomized non-autonomous complete linear differential equation by assuming that the diffusion coefficient and the source term are stochastic processes and the initial condition is a random variable. The key tools to construct these approximations are the random variable transformation technique and Karhunen-Loeve expansions. The study is divided into a large number of cases with a double aim: firstly, to extend the available results in the extant literature and, secondly, to embrace as many practical situations as possible. Finally, a wide variety of numerical experiments illustrate the potentiality of our findings.

Submitted July 2, 2018. Published July 16, 2019.
Math Subject Classifications: 34F05, 60H35, 60H10, 65C30, 93E03.
Key Words: Random non-autonomous complete linear differential equation; random variable transformation technique; Karhunen-Loeve expansion; probability density function.

Show me the PDF file (690 KB), TEX file for this article.

Julia Calatayud
Instituto Universitario de Matemática Multidisciplinar
Universitat Politècnica de València
Camino de Vera s/n, 46022, Valencia, Spain
email: jucagre@doctor.upv.es
Juan Carlos Cortés
Instituto Universitario de Matemática Multidisciplinar
Universitat Politècnica de València
Camino de Vera s/n, 46022, Valencia, Spain
email: jccortes@imm.upv.es
Marc Jornet
Instituto Universitario de Matemática Multidisciplinar
Universitat Politècnica de València
Camino de Vera s/n, 46022, Valencia, Spain
email: marjorsa@doctor.upv.es

Return to the EJDE web page