excProb: Exceedance probabilities
In geostatsp: Geostatistical Modelling with Likelihood and Bayes

Description Usage Arguments Details Value Examples

Calculate exceedance probabilities pr(X > threshold) from a fitted geostatistical model.

1 2	excProb(x, threshold=0, random=FALSE, template=NULL, templateIdCol=NULL, nuggetInPrediction=TRUE)

`x`	Output from either the `lgm` or `glgm` functions, or a list of two-column matrices with columns named `x` and `y` containing the posterior distributions of random effects, as produced by `inla`.
`threshold`	the value which the exceedance probability is calculated with respect to.
`random`	Calculate exceedances for the random effects, rather than the predicted observations (including fixed effects).
`template`	A `Raster` or `SpatialPolygonsDataFrame` or `SpatialPointsDataFrame` object which the results will be contained in.
`templateIdCol`	The data column in `template` corresponding to names of `marginals`
`nuggetInPrediction`	If `TRUE`, calculate exceedance probabilities of new observations by adding the nugget effect. Otherwise calculate probabilities for the latent process. Ignored if `x` is output from `glgm`.

When x is the output from lgm, pr(Y>threshold) is calculated using the Gaussian distribution using the Kriging mean and conditional variance. When x is from the glgm function, the marginal posteriors are numerically integrated to obtain pr(X > threshold).

Either a vector of exceedance probabilities or an object of the same class as template.

	data('swissRain')
	swissFit =  lgm("rain", swissRain, grid=30, 
	boxcox=0.5,fixBoxcox=TRUE,	covariates=swissAltitude)
	swissExc = excProb(swissFit, 20)
	mycol = c("green","yellow","orange","red")
	mybreaks = c(0, 0.2, 0.8, 0.9, 1)
	plot(swissBorder)
	plot(swissExc, breaks=mybreaks, col=mycol,add=TRUE,legend=FALSE)
	plot(swissBorder, add=TRUE)
	legend("topleft",legend=mybreaks, col=c(NA,mycol))
## Not run: 
	swissRain$sqrtrain = sqrt(swissRain$rain)
	swissFit2 =  glgm(formula="sqrtrain",data=swissRain, grid=40, 
	covariates=swissAltitude,family="gaussian")
	swissExc = excProb(swissFit2, threshold=sqrt(30))
	swissExc = excProb(swissFit2$inla$marginals.random$space, 0,
		template=swissFit2$raster)

## End(Not run)