PERT distribution with alternative parameters | Vose Software

PERT distribution with alternative parameters

Format: PERTAlt(Low, Mode, High, LowP, HighP)


This alternative parameterization of the PERT distribution is useful for modeling expert estimates of some continuous quantity.

The PERTAlt distribution appears in ModelRisk's standard Select Distribution palette. It also appears in ModelRisk's Expert selector window when one selects two percentiles {(LowP, Low), (HighP, High)} and a mode.

ModelRisk has another distribution that can be used with this alternative parametisation: the TriangleAlt. It is a good idea to compare the two distributions together to see which gives the most realistic interpretation of the input parameters.

ModelRisk functions added to Microsoft Excel for the Alternative-Parameter PERT distribution

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

VosePERTAltObject constructs a distribution object for this distribution.

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

VosePERTAltProb10 returns the log10 of the probability density or cumulative distribution function. 


Alternative-Parameter PERT distribution equations



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