Variogram {nlme}

Calculate Semi-variogram

Description

This function is generic; method functions can be written to handle specific classes of objects. Classes which already have methods for this function include default, gls and lme. See the appropriate method documentation for a description of the arguments.

Usage

Variogram(object, distance, ...)

Arguments

object

a numeric vector with the values to be used for calculating the semi-variogram, usually a residual vector from a fitted model.

distance

a numeric vector with the pairwise distances corresponding to the elements of object. The order of the elements in distance must correspond to the pairs (1,2), (1,3), ..., (n-1,n), with n representing the length of object, and must have length n(n-1)/2.

...

some methods for this generic function require additional arguments.

Value

will depend on the method function used; see the appropriate documentation.

Author(s)

José Pinheiro and Douglas Bates [e-mail]

References

Cressie, N.A.C. (1993), "Statistics for Spatial Data", J. Wiley & Sons.

Pinheiro, J.C., and Bates, D.M. (2000) "Mixed-Effects Models in S and S-PLUS", Springer.

See Also

Variogram.corExp, Variogram.corGaus, Variogram.corLin, Variogram.corRatio, Variogram.corSpatial, Variogram.corSpher, Variogram.default, Variogram.gls, Variogram.lme, plot.Variogram

Examples

## see the method function documentation