library(StatDA)
data(moss)
data(kola.background)
X=moss[,"XCOO"]
Y=moss[,"YCOO"]
sel=c("Ag","Al","As","B","Ba","Bi","Ca","Cd","Co","Cr","Cu","Fe","Hg","K","Mg",
"Mn","Mo","Na","Ni","P","Pb","Rb","S","Sb","Si","Sr","Th","Tl","U","V","Zn")
x=log10(moss[,sel])
set.seed(100)
x.mcd=covMcd(x,cor=TRUE)
# robust scaling
x.rsc=scale(x,x.mcd$cent,sqrt(diag(x.mcd$cov)))
# robust PFA
res=pfa(x.rsc,factors=5,covmat=x.mcd,scores="regression",rotation="varimax")
# classical PFA
res1=pfa(scale(x),factors=5,scores="regression",rotation="varimax")
pdf("fig-14-13.pdf",width=8,height=8)
par(mfrow=c(2,1),mar=c(2,3,3,1))
loadplot(res,titlepl="Robust FA", crit=0.3)
loadplot(res1,titlepl="Classical FA", crit=0.3)
dev.off()