cdfBetaInv

Purpose

Computes the quantile or inverse of the Beta cumulative distribution function.

Format

x = cdfBetaInv(p, a, b)

Parameters:

• p (NxK matrix, Nx1 vector or scalar) – Probabilities at which to compute the inverse of the Beta cumulative distribution function. \(0 \lt p \lt 1\)

• a (LxM matrix) – ExE conformable with p. \(a > 0\)

• b (PxQ matrix) – ExE conformable with p and a. \(b > 0\)

Returns:

x (NxK matrix, Nx1 vector or scalar) – Each value of X is the value which if passed to cdfBeta() will return the corresponding value of P.

Examples

// List of probabilities
p = { 0.10, 0.20, 0.30, 0.40 };

// Beta parameters
a = 0.5;
b = 0.3;

// Call cdfBetaInv
x = cdfBetaInv(p, a, b);
print "x = "        x;

After running the above code,

x =
  0.0506
  0.1886
  0.3781
  0.5763

Remarks

For invalid inputs, cdfBetaInv() will return a scalar error code which, when its value is assessed by function scalerr(), corresponds to the invalid input. If the first input is out of range, scalerr() will return a 1; if the second is out of range, scalerr() will return a 2; etc.

See also

Functions cdfBeta(), cdfBinomial(), cdfNegBinomial()