Default boundaries for covariance parameters.
covParametersBounds(object, X)
an object specifying the covariance structure.
a matrix representing the design of experiments.
a list with items lower, upper
containing default boundaries for the covariance parameters.
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 |