GeoPit: Probability integral or normal score transformation

In GeoModels: Procedures for Gaussian and Non Gaussian Geostatistical (Large) Data Analysis

Probability integral or normal score transformation

Description

For a given GeoFit, the procedure applies either the probability integral transformation or the normal score transformation to the data.

Usage

GeoPit(object, type = "Uniform")

Arguments

object	An object of class GeoFit, GeoKrig, or GeoKrigloc. For fitted models with covariates, the GeoFit object must first be transformed by GeoResiduals.
type	The type of transformation. If "Uniform", the probability integral transformation is performed. If "Gaussian", the normal score transformation is performed.

Value

Returns an (updated) object of class GeoFit

Author(s)

Moreno Bevilacqua, [e-mail],https://sites.google.com/view/moreno-bevilacqua/home, Víctor Morales Oñate, [e-mail], https://sites.google.com/site/moralesonatevictor/, Christian Caamaño-Carrillo, [e-mail],https://www.researchgate.net/profile/Christian-Caamano

Examples

library(GeoModels)

model="Beta2"
copula="Clayton"

set.seed(221)
NN=800
x <- runif(NN);y <- runif(NN)
coords=cbind(x,y)


shape=1.5
scale=0.2;power2=4
smooth=0
nugget=0
nu=8

corrmodel="GenWend"

min=-2;max=1
mean=0


param=list(smooth=smooth,power2=power2, min=min,max=max,
 mean=mean, nu=nu,
 scale=scale,nugget=nugget,shape=shape)

optimizer="nlminb"

data <- GeoSimCopula(coordx=coords, corrmodel=corrmodel, 
model=model,param=param,copula=copula)$data

I=50
fixed<-list(nugget=nugget,sill=1,scale=scale,smooth=smooth,power2=power2,min=min,max=max,nu=nu)
start<-list(shape=shape,mean=mean)
lower<-list(shape=0,mean=-I)
upper<-list(shape=10,mean=I)

#### maximum independence likelihood
fit1 <- GeoFit(data=data,coordx=coords,corrmodel=corrmodel,
model=model,likelihood="Marginal",type="Independence",
 optimizer=optimizer,lower=lower,
 upper=upper,copula=copula,
 start=start,fixed=fixed)

## PIT transformation
aa=GeoPit(fit1,type="Uniform")
hist(aa$data,freq=FALSE)
GeoScatterplot(aa$data,coords,neighb=c(1,2))
## Normal score transformation
bb=GeoPit(fit1,type="Gaussian")
hist(bb$data,freq=FALSE)
GeoScatterplot(bb$data,coords,neighb=c(1,2))

GeoModels documentation built on July 29, 2026, 5:06 p.m.