I did no analysis of your code or thought process, but noticed that you had the following two successive lines in your code:
y=Testing$wage y=Wage[-sam,]$wage This obviously makes no sense, so maybe you should fix this first and then proceed. -- Bert Bert Gunter "The trouble with having an open mind is that people keep coming along and sticking things into it." -- Opus (aka Berkeley Breathed in his "Bloom County" comic strip ) On Mon, Oct 29, 2018 at 1:46 PM varin sacha via R-help <r-help@r-project.org> wrote: > > Dear R-experts, > I am having trouble while doing crossvalidation with a MARS regression > including an interaction term between a factor variable (education) and 1 > continuous variable (age). How could I solve my problem ? > > Here below my reproducible example. > > ####### > > install.packages("ISLR") > > library(ISLR) > > install.packages("earth") > > library(earth) > > a<-as.factor(Wage$education) > > # Create a list to store the results > > lst<-list() > > # This statement does the repetitions (looping) > > for(i in 1 :200) { > > n=dim(Wage)[1] > > p=0.667 > > sam=sample(1 :n,floor(p*n),replace=FALSE) > > Training =Wage [sam,] > > Testing = Wage [-sam,] > > mars5<-earth(wage~age+education+year+age*a, data=Wage) > > ypred=predict(mars5,newdata=Testing) > > y=Testing$wage > > y=Wage[-sam,]$wage > > MSE = mean(y-ypred)^2 > > MSE > > lst[i]<-MSE > > } > > mean(unlist(lst)) > > summary(mars5) > > ####### > > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide > http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. > [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.