| RMgenfbm {RandomFields} | R Documentation |
RMgenfbm is an intrinsically stationary isotropic
variogram model.
The corresponding centered semi-variogram only depends on the distance
r ≥ 0 between two points and is given by
γ(r)=(r^{α}+1)^{β/α}-1
where 0 < α ≤ 2 and β \in (0,2].
See also RMfbm.
RMgenfbm(alpha, beta, var, scale, Aniso, proj)
alpha |
a numerical value; should be in the interval (0,2]. |
beta |
a numerical value; should be in the interval (0,2]. |
var,scale,Aniso,proj |
optional arguments; same meaning for any
|
Here, the variogram of RMfbm is modified by
the transformation (γ+1)^{δ/-1} on variograms
γ
for δ \in (0,1]. This original modification allows for
further generalization, cf. RMbcw.
RMgenfbm returns an object of class RMmodel.
Martin Schlather, schlather@math.uni-mannheim.de, https://www.wim.uni-mannheim.de/schlather/
Gneiting, T. (2002) Nonseparable, stationary covariance functions for space-time data, JASA 97, 590-600.
Schlather, M. (2010) On some covariance models based on normal scale mixtures. Bernoulli, 16, 780-797.
RMbcw,
RMfbm,
RMmodel,
RMflatpower,
RFsimulate,
RFfit.
RFoptions(seed=0) ## *ANY* simulation will have the random seed 0; set ## RFoptions(seed=NA) to make them all random again model <- RMgenfbm(alpha=1, beta=0.5) x <- seq(0, 10, 0.02) plot(model) plot(RFsimulate(model, x=x))