| Variogram.corSpatial {nlme} | R Documentation |
Calculate Semi-variogram for a corSpatial Object
Description
This method function calculates the semi-variogram values
corresponding to the model defined in FUN, using the estimated
coefficients corresponding to object, at the distances defined
by distance.
Usage
## S3 method for class 'corSpatial'
Variogram(object, distance, sig2, length.out, FUN, ...)
Arguments
object |
an object inheriting from class |
distance |
an optional numeric vector with the distances at
which the semi-variogram is to be calculated. Defaults to
|
sig2 |
an optional numeric value representing the process
variance. Defaults to |
length.out |
an optional integer specifying the length of the
sequence of distances to be used for calculating the semi-variogram,
when |
FUN |
a function of two arguments, the distance and the range
corresponding to |
... |
some methods for this generic require additional arguments. None are used in this method. |
Value
a data frame with columns variog and dist representing,
respectively, the semi-variogram values and the corresponding
distances. The returned value inherits from class Variogram.
Author(s)
José Pinheiro and Douglas Bates bates@stat.wisc.edu
References
Cressie, N.A.C. (1993), "Statistics for Spatial Data", J. Wiley & Sons.
See Also
corSpatial,
Variogram,
Variogram.default,
Variogram.corExp,
Variogram.corGaus,
Variogram.corLin,
Variogram.corRatio,
Variogram.corSpher,
plot.Variogram
Examples
cs1 <- corExp(3, form = ~ Time | Rat)
cs1 <- Initialize(cs1, BodyWeight)
Variogram(cs1, FUN = function(x, y) (1 - exp(-x/y)))[1:10,]