Default boundaries for covariance parameters.
covParametersBounds(object, X)a list with items lower, upper containing default boundaries for the covariance parameters.
an object specifying the covariance structure.
a matrix representing the design of experiments.
Olivier Roustant, David Ginsbourger, Ecole des Mines de St-Etienne.
The default values are chosen as follows :
| Range parameters (all covariances) | lower=1e-10, upper=2 times the difference between |
the max. and min. values of X for each coordinate | |
Shape parameters (powexp covariance) | lower=1e-10, upper=2 for each coordinate |
km