Vose Exponential Lifetime Distribution | Vose Software

Vose Exponential Lifetime Distribution

Format: LifetimeExp(a,b,c)


The Exponential Lifetime distribution is a lifetime distribution with an instantaneous failure rate given by:




The Exponential LifetimeExp distribution is useful for modelling the lifetime of a device where the instantaneous failure rate increases more dramatically over time than linearly.


The two-parameter lifetime distribution was first developed by the risk analyst, David Vose.

ModelRisk functions added to Microsoft Excel for the Vose Exponential Lifetime distribution

VoseLifetimeExp generates random values from this distribution for Monte Carlo simulation, or calculates a percentile if used with a U parameter.

VoseLifetimeExpObject constructs a distribution object for this distribution.

VoseLifetimeExpProb returns the probability density or cumulative distribution function for this distribution.

VoseLifetimeExpProb10 returns the log10 of the probability density or cumulative distribution function.

VoseLifetimeExpFit generates values from this distribution fitted to data, or calculates a percentile from the fitted distribution.

VoseLifetimeExpFitObject constructs a distribution object of this distribution fitted to data.

VoseLifetimeExpFitP returns the parameters of this distribution fitted to data.


Exponential Lifetime Distribution equations