stmin <- read.csv("http://www.stat.ufl.edu/~winner/sta4210/mydata/state_mineral.csv",header=TRUE) attach(stmin); names(stmin) # install.packages("rpart") library(rpart) (mintree1 <- rpart(lnValue ~ lnAREA,stmin,method="anova",cp=.0001)) plot(mintree1,margin=.10) text(mintree1) plot(mintree1,compress=T,uniform=T,branch=0.4,margin=.10) text(mintree1) printcp(mintree1) plotcp(mintree1) minr <- prune.rpart(mintree1,.017) 1-sum(residuals(minr)^2)/sum((lnValue-mean(lnValue))^2)