WorksheetFunction.Beta_Inv Method (Excel)
Returns the inverse of the cumulative distribution function for a specified beta distribution. That is, if probability = Beta_Dist(x,...), then Beta_Inv(probability,...) = x.
Version Information
Version Added: Excel 2010
Syntax
expression .Beta_Inv(Arg1, Arg2, Arg3, Arg4, Arg5)
expression A variable that represents a WorksheetFunction object.
Parameters
Name |
Required/Optional |
Data Type |
Description |
---|---|---|---|
Arg1 |
Required |
Double |
A probability associated with the beta distribution. |
Arg2 |
Required |
Double |
The Alpha parameter of the distribution. |
Arg3 |
Required |
Double |
The Beta parameter the distribution. |
Arg4 |
Optional |
Variant |
An optional lower bound to the interval of x. |
Arg5 |
Optional |
Variant |
An optional upper bound to the interval of x. |
Return Value
Double
Remarks
The beta distribution can be used in project planning to model probable completion times given an expected completion time and variability:
If any argument is nonnumeric, Beta_Inv generates an error value.
If alpha ≤ 0 or beta ≤ 0, Beta_Inv generates an error value.
If probability ≤ 0 or probability > 1, Beta_Inv generates an error value.
If you omit values for A and B (lower and upper bound), Beta_Inv uses the standard cumulative beta distribution, so that A = 0 and B = 1.
Given a value for probability, Beta_Inv seeks that value x such that Beta_Dist(x, alpha, beta, TRUE, A, B) = probability. Thus, precision of Beta_Inv depends on precision of Beta_Dist. Beta_Inv uses an iterative search technique.