Vose Two-Parameter Lifetime distribution | Vose Software

Vose Two-Parameter Lifetime distribution

Format: Lifetime2((a,b)

The Two-Parameter Lifetime distribution is a lifetime distribution with an instantaneous failure rate given by:




The Two-Parameter Lifetime distribution is an interesting alternative to the Weibull distribution since, unlike the Weibull, it allows a non-zero instantaneous failure rate at the beginning of the life of a device.


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

ModelRisk functions added to Microsoft Excel for the Vose Two-Parameter Lifetime distribution

VoseLifetime2 generates random values from this distribution for Monte Carlo simulation, or calculates a percentile if used with a U parameter.

VoseLifetime2Object constructs a distribution object for this distribution.

VoseLifetime2Prob returns the probability density or cumulative distribution function for this distribution.

VoseLifetime2Prob10 returns the log10 of the probability density or cumulative distribution function.

VoseLifetime2Fit generates values from this distribution fitted to data, or calculates a percentile from the fitted distribution.

VoseLifetime2FitObject constructs a distribution object of this distribution fitted to data.

VoseLifetime2FitP returns the parameters of this distribution fitted to data.


Two-Parameter Lifetime distribution equations



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