data(weeds.covariates)
x
y
sheep
strip
weeds
data that were provided by Melville and Welsh (see reference below) that
were used in the Biometrics paper on distance sampling.The code used to create the covariate grid was as follows:
xx=expand.grid(seq(5,1195,10),seq(5,1195,10)) weeds.covariates=data.frame(x=xx$Var2,y=xx$Var1, sheep=rep(c(0,1),each= 120^2/2), strip=rep(c(1,2,3,4,5,6,7,8),each=120^2/8)) save(weeds.covariates,file="weeds.covariates.rda")