The Archimedean generator function and its inverse.
Usage
phi(x, theta, type)
phi.inv(x, theta, type)
Arguments
x
a scalar, vector or matrix at which the function is evaluated. The support of the functions has to be taken into account, i.e. \(x \in [0, \infty]\) for the generator function and \(x \in [0, 1]\) for its inverse.
theta
the feasible copula parameter, i.e. \(\theta \in [1, \infty)\) for the Gumbel and Joe family, \(\theta \in (0, \infty)\) for the Clayton and Frank family and \(\theta \in [0, 1)\) for the Ali-Mikhail-Haq family.
type
select between the following integer numbers for specifying the type of the hierarchical Archimedean copula (HAC) or Archimedean copula (AC):
x = runif(100, min = 0, max = 100)
phi(x, theta = 1.2, type = 1)
# do not run# phi(x, theta = 0.8, type = 1) # In phi(x, theta = 0.8, type = 1) : theta >= 1 is required.