SpatioTemporal (version 0.9.2)

remove.ST.mean: Mean-Centre the Spatio-Temporal Covariate

Description

Removes the temporal mean at each location for the spatio-temporal covariares. The means are added to the returned data structure and can be used as geographic covariates.

Usage

remove.ST.mean(mesa.data)

Arguments

mesa.data

Data structure holding observations, observation locations, smooth temporal trends, geographic covariates and spatio-temporal covariates. See mesa.data.

Value

• Returns a modfied version of the input mesa.data, where the site by site temporal average has been removed from each of the spatio-temporal covariates. The averages are seen as geographic covariates and added to mesa.data$LUR.

encoding

latin1

Examples

##load data
data(mesa.data)

mesa.data.mean0 <- remove.ST.mean(mesa.data)

##compare the data structures
##geographic covariates
summary(mesa.data$LUR)
summary(mesa.data.mean0$LUR)

##mean of the spatio-temporal covariate
cbind(colMeans(mesa.data$SpatioTemp),
      colMeans(mesa.data.mean0$SpatioTemp))

##mean of the spatio-temporal covariate
##compared to the added mean covariate
plot(mesa.data.mean0$LUR$mean.lax.conc.1500,
     colMeans(mesa.data$SpatioTemp))
if( max(abs(colMeans(mesa.data.mean0$SpatioTemp))) > 1e-10 ){
  stop("remove.ST.mean 1: mean(centred ST) != 0")
}
if( max(abs(mesa.data.mean0$LUR$mean.lax.conc.1500 - 
            colMeans(mesa.data$SpatioTemp))) > 1e-10 ){
  stop("remove.ST.mean 2: extracted mean != mean(ST)")
}