Hi everyone,
I am doing BRT modelling using Elith et al. (2008) R functions script which is given as supplementary materials in their publication. I hope most you seen it once a while. I have a doubt that what is meant for "100" in this script? They were used 1000 sites data for modelling.
# create a vector of randomised numbers and feed into presences
selector <- rep(0,n.cases)
temp <- rep(seq(1, n.folds, by = 1), length = n.pres)
temp <- temp[order(runif(n.pres, 1, 100))]
selector[presence.mask] <- temp
# and then do the same for absences
temp <- rep(seq(1, n.folds, by = 1), length = n.abs)
temp <- temp[order(runif(n.abs, 1, 100))]
selector[absence.mask] <- temp
}
else { #otherwise make them random with respect to presence/absence
selector <- rep(seq(1, n.folds, by = 1), length = n.cases)
selector <- selector[order(runif(n.cases, 1, 100))]
}
}