3.5.3.3.1 Betainv

Betainv-func

Description

Returns the inverse of the cumulative distribution function for a specified beta distribution.The beta distribution is useful in project planning to model probable completion times given an expected completion time and variability.

Syntax

BETAINV(double probability, double alpha, double beta)

Parameters

Probability

a probability associated with the beta distribution.

Alpha

The first shape parameter of the distribution.

Beta

The second shape parameter of the distribution

Return

Returns the inverse of the cumulative distribution function for a specified beta distribution.

Example

double bb = betainv(0.8975362,8,10);
bb = ;//Should return 0.5928749129231.