beta_inv

The beta_inv function returns the inverse of the beta cumulative probability beta density function.

The beta distribution can be used in project planning to model probable completion times given an expected completion time and variability.

Syntax

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    beta_inv( Probability, Alpha, Beta )

Arguments

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• Probability: A probability associated with the beta distribution.
• Alpha: A parameter of the distribution.
• Beta: A parameter of the distribution.

Returns

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The inverse of the beta cumulative probability density function beta_cdf.

Note:

• If any argument is nonnumeric, beta_inv returns null value.
• If alpha ≤ 0 or beta ≤ 0, beta_inv returns the null value.
• If probability ≤ 0 or probability > 1, beta_inv returns the NaN value.
• Given a value for probability, beta_inv seeks that value x such that beta_cdf(x, alpha, beta) = probability.