kmNoNugget.init {DiceKriging} | R Documentation |
Fitting Kriging Models
Description
kmNoNugget.init
is used to give initial values to fit kriging models when there is no nugget effect nor noisy observations.
Usage
kmNoNugget.init(model, fn, fnscale)
Arguments
model |
an object of class |
fn |
the function considered: |
fnscale |
a real number which sign determines the direction for optimization: <0 for |
Details
The procedure can be summarized in 2 stages:
1) | If no initial value is provided by the user for the covariance parameters, simulate them uniformly inside the domain delimited by model@lower and model@upper . The number of simulations is the one given in model@control$pop.size . |
2) | Compute the likelihood for each parameters set, and select the one(s) that gives the highest value(s). The number of values considered can be set by the argument multistart in km .
|
Value
par |
a matrix whose rows contain initial vectors of parameters. |
value |
a vector containing the function values corresponding to |
cov |
a list containing the covariance objects corresponding to |
lower |
, |
upper |
vectors containing lower and upper bounds for parameters. |
Author(s)
O. Roustant, David Ginsbourger, Ecole des Mines de St-Etienne.
See Also
[Package DiceKriging version 1.6.0 Index]