Archivos por etiqueta: spatial data

Generating spatially correlated random fields with R

In several occasions I needed to generate synthetic data with a desired level of spatial autocorrelation. Here I will show how to generate as many such fields as we need by using R, an open-source port of the S language for statical analysis. I will concentrate on two alternative ways of generating spatially correlated random fields (commonly known as unconditional […]

Generalized Least Squares regression: regression models with spatial autocorrelation

This is the R code for performing Generalized Least Squares regression without (mod0) and with spatial autocorrelation (mod1), using the gls function in the library nlme: # first load the nlme library library(nlme) # read data (forest recovery after forest fire) # 30000 cells from satellite imagery datos — read.csv(‘variables.csv’, sep=’;’, head=T) # create matrices to […]