LogLogisticAlt distribution

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Format: VoseLogLogisticAlt(value1, probability1, value2, probability2 ,minimum,  U)

LogLogisticAlt equations

Uses

This alternative parameterization of the LogLogistic distribution is useful for modeling expert estimates of some continuous quantity with a long right tail, like time or cost to complete a task.

The LogLogisticAlt distribution appears in the standard Select Distribution palette. It also appears in the Expert selector window when one selects two percentiles {(P1, X1), (P2, X2)} and a minimum.

ModelRisk has two other distributions that can be used with this alternative parametisation: the LognormalAlt and the WeibullAlt. It is a good idea to compare all three distributions together to see which gives the most realistic interpretation of the input parameters.

VoseFunctions for this distribution

VoseLogLogisticAlt generates values from this distribution or calculates a percentile.

VoseLogLogisticAltObject constructs a distribution object for this distribution. Professional and Industrial editions only.

VoseLogLogisticAltProb returns the probability density or cumulative distribution function for this distribution. Professional and Industrial editions only.

VoseLogLogisticAltProb10 returns the log10 of the probability density or cumulative distribution function. Professional and Industrial editions only.