| GGamma {gestate} | R Documentation |
Generalised Gamma Curve constructor function
Description
This creates a Curve object for a Generalised Gamma distribution.
Curve objects contain all necessary information to describe a distribution, including functions and parameters describing it.
See Details for information on parameterisation.
Usage
GGamma(theta, eta, rho)
Arguments
theta |
Scale parameter for Generalised Gamma distribution. |
eta |
Shape parameter for Generalised Gamma distribution. |
rho |
Family parameter for Generalised Gamma distribution. |
Details
The Generalised Gamma distribution has parameterisation:
f(x) = (rho x^((rho eta)-1) e^(-(x/theta)^rho) theta^(-rho eta) )/Gamma(eta)
F(x) = LPGamma(eta,(x/theta)^rho)/Gamma(eta)
where Gamma is the gamma function, and LPGamma is the lower partial gamma function.
As of v1.4.0, all values of eta are now fully supported.
Author(s)
Jasmin Ruehl
References
Tadikamalla PR, Random Sampling from the Generalized Gamma Distribution. Computing, 1979, 23(2), 199-203.
Examples
GGamma(theta=20,eta=2,rho=0.7)