Here is my original script. subject=1:1000 treat=rbinom(1*1000,1,.13) gender=rbinom(1*1000,1,.5) eth=runif(1*1000, min=1, max=4) cogat=rnorm(1*1000, 100, 16) map=rnorm(1*1000, 200, 9) growth=0 simtest=data.frame (subject=subject, treat=treat, gender=gender, eth=round(eth,digits=0), cogat=round(cogat,digits=0),map=round(map,digits=0),growth) simtest<-transform(simtest, growth=rnorm(1000,m=ifelse(treat==0,0.1,0.5),s=0.03)) simtest
The categorical variable I'm looking at is "eth." I want to change it to a factor. The code you gave works great by itself, but I can't apply it to this program. Sorry! I'm really new to this. Thanks for your help! Shane -----Original Message----- From: Dr. Pablo E. Verde [mailto:pabloemilio.ve...@uni-duesseldorf.de] Sent: Tuesday, April 12, 2011 8:53 AM To: andrija djurovic; Shane Phillips Cc: r-help@r-project.org Subject: Re: [R] Converting a categorical variable to multiple dichotemousvariables Hi Shane, An alternative is: cat<-as.factor(c(1,1,3,2,4)) outer(cat, levels(cat), "==")+0 Cheers, Pablo ----- Original Message ----- From: "andrija djurovic" <djandr...@gmail.com> To: "Shane Phillips" <sphill...@lexington1.net> Cc: <r-help@r-project.org> Sent: Tuesday, April 12, 2011 2:32 PM Subject: Re: [R] Converting a categorical variable to multiple dichotemousvariables > hi: > here is one solution: > > cat<-as.factor(c(1,1,3,2,4)) > model.matrix(~cat-1,cat) > > cbind(cat,model.matrix(~cat-1,cat)) > Andrija > > On Tue, Apr 12, 2011 at 2:17 PM, Shane Phillips > <sphill...@lexington1.net>wrote: > >> I have a categorical variable in a dataframe similar to the following... >> >> cat >> 1 >> 1 >> 3 >> 2 >> 4 >> >> I need to convert it to 4 dichotemous variables for each observations >> like... >> >> cat1 cat2 cat3 cat4 >> 1 0 0 0 >> 1 0 0 0 >> 0 0 1 0 >> 0 1 0 0 >> 0 0 0 1 >> >> >> Thanks in advance! >> >> Shane >> >> ______________________________________________ >> 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<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 > 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. > ______________________________________________ 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.
