[R] error in lm

[Greg Snow]

First your response in the formula is a matrix which causes the lm
function to return an object of type 'mlm' for multivariate linear
model.  Then when you run the stepAIC function it runs the addterm
function which looks for a method(function) to add terms to mlm
objects.  However nobody has written that particular method/function
(at least not in the packages that you have loaded), that's what it
means by 'no addterm method implemented for "mlm" models'.

You can write your own method, redo the process using only 1 response
term at a time, wait for someone else to write this method (it will
probably be a long wait unless you provide sufficient motivation), or
use other techniques (stepwise regression is not the best tool
anymore).

On Tue, Oct 30, 2012 at 4:51 AM, paola <aikaterini07 at hotmail.com> wrote:
> Hi everybody
>
> I am trying to run the next code but I have the next problem
>
> Y1<-cbind(score.sol, score.com.ext, score.pur)
>> vol.lm<-lm(Y1~1, data=vol14.df)
>> library(MASS)
>> stepAIC(vol.lm,~fsex+fjob+fage+fstudies,data=vol14.df)
> Start:  AIC=504.83
> Y1 ~ 1
>
> Error in addterm.mlm(fit, scope$add, scale = scale, trace = max(0, trace -
> :
>   no addterm method implemented for "mlm" models
>
> Does anybody knows why I get this error?
>
> Thanks in advance
> Paola
>
>
>
> --
> View this message in context: http://r.789695.n4.nabble.com/error-in-lm-tp4647840.html
> Sent from the R help mailing list archive at Nabble.com.
>
> ______________________________________________
> R-help at 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.



-- 
Gregory (Greg) L. Snow Ph.D.
538280 at gmail.com