lambda.HR: Valid set of parameters for the 3-dimensional Husler-Reiss model.
Description
Given two parameters of the Husler-Reiss model, this function evaluates the range of values the third parameter can take to ensure a positive definite matrix in the model.
Usage
lambda.HR(lambda)
Value
A \(2 \times 3\) matrix with, ont top, the lowest value of the parameter corresponding to the NA value in the input, and on the bottom the largest value.
Arguments
lambda
A vector of length 3 containing one NA and two positive values. The NA corresponds to the parameter for which the range is calculated.
As indicated in Engelke et al (2015), the matrix with 0 diagonal and squared lambda parameters on the off-diagonal needs to be strictly conditionally ngeative definite.
References
Engelke, S., Malinowski, A., Kabluchko, Z., and Schlather, M. (2015),
Estimation of Husler-Reiss distributions and Brown-Resnick processes,
Journal of the Royal Statistical Society, Series B (Methodological), 77, 239--265.