> -----Original Message----- > From: r-help-boun...@r-project.org > [mailto:r-help-boun...@r-project.org] On Behalf Of Hongwei Dong > Sent: Monday, August 03, 2009 2:26 PM > To: r-help@R-Project.org > Subject: [R] What does this error message mean? > > Hi, I used R to run a linear regression and keep getting the > following error > message. I do not understand it very well. Anyone can help > out? Thanks. > > Error in storage.mode(y) <- "double" : > invalid to change the storage mode of a factor > In addition: Warning message: > In model.response(mf, "numeric") : > using type="numeric" with a factor response will be ignored
I see the words 'response' , 'factor', and 'numeric' in that message and think that it has to do with lm() only being defined for numeric response variables, not factor (categorical) responses. E.g., > d<-data.frame(fac=letters[c(1:3,1:3)], x=1:6) > lm(data=d, fac~x) Error in storage.mode(y) <- "double" : invalid to change the storage mode of a factor In addition: Warning message: In model.response(mf, "numeric") : using type="numeric" with a factor response will be ignored If you had showed us your dataset and your command we could say for sure if this was the problem. The error message alone is rarely as informative as this one. Bill Dunlap TIBCO Software Inc - Spotfire Division wdunlap tibco.com > > [[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.