Publication TypeJournal Article
Year of Publication2018
Start Page271
Date Published2018
AMS34F05, 60H10, 92C30, 92D25

A family of stochastic differential equation (SDE) models is derived and studied for the aging of biological organisms. The SDE aging models give meaningful mathematical interpretations of the aging process, rate of aging, and maximum age. For the SDE models, the first passage time gives the time to death. Probability densities of first passage times are derived for the SDE models yielding theoretical death event densities. The derived death event probability densities are fitted, using maximum likelihood estimation, to several different mortality table datasets. Mortality data for humans, wild sheep, grasshoppers, and fruit flies are considered. The results of fitting the mortality data indicate that the rate of aging for humans and many other animals undergoes an increase at some point in time.

Refereed DesignationRefereed
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