You real error was this: Error in pre[sam[[j]], i] <- predict(fit, data = dat[sam[[j]], ]) : number of items to replace is not a multiple of replacement length
Take a look at the statement and you will see that 'predict' is returning 100 values and you are trying to store it into only 10 rows (that is what sam[[j]] is). You need to rethink what you are trying to do. Let me ask my favorite question: what is the problem you are trying to solve? On Mon, Jun 20, 2011 at 8:05 AM, zhu yao <mailzhu...@gmail.com> wrote: > error in pre[sam[[j]], i] <- predict(fit, data = dat[sam[[j]], ]) : > > Yao Zhu > Department of Urology > Fudan University Shanghai Cancer Center > Shanghai, China > > > 2011/6/20 Jim Holtman <jholt...@gmail.com> >> >> what was the error? >> >> Sent from my iPad >> >> On Jun 20, 2011, at 1:34, zhu yao <mailzhu...@gmail.com> wrote: >> >> > Dear R users: >> > >> > Recently, I tried to write a program to calculate cross-validated >> > predicted >> > value. >> > My sources are as follows. However, the R reported an error. >> > Could you please check the sources? Thanks. >> > >> > set.seed(100) >> > x<-rnorm(100) >> > y<-sample(rep(0:1,50),replace=T) >> > dat<-data.frame(x,y) >> > >> > library(rms) >> > >> > fito<-lrm(y~x) >> > preo<-predict(fito) >> > >> > pre<-matrix(NA,nrow=100,ncol=200) >> > >> > for (i in 1:200) >> > { >> > sam<-sample(1:nrow(dat)) >> > sam<-split(sam,1:10) >> > for (j in 1:10) >> > { >> > fit<-lrm(y~x,data=dat[-sam[[j]],]) >> > pre[sam[[j]],i]<-predict(fit,data=dat[sam[[j]],]) >> > } >> > } >> > >> > >> > >> > >> > >> > >> > >> > >> > *Yao Zhu* >> > *Department of Urology >> > Fudan University Shanghai Cancer Center >> > Shanghai, China* >> > >> > [[alternative HTML version deleted]] >> > >> > ______________________________________________ >> > R-help@r-project.org mailing list >> > 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. > > -- Jim Holtman Data Munger Guru What is the problem that you are trying to solve? ______________________________________________ R-help@r-project.org mailing list 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.