Hi Denis,
how about this:
to.drop<-"x1"
update(mod,as.formula(paste(".~.-",to.drop,sep="")))
hth.
Am 22.03.2011 08:12, schrieb Denis.Aydin at unibas.ch:> Dear all
>
> I want to run a simple multiple linear regression model, say:
>
> mod <- lm(y~x1+x2+x3+x4)
>
> I have programmed a custom algorithm to calculate the p-values, because
> there is clustering present.
>
> I ordered the variables according to their p-value and want to stepwise
> eliminate the variables with the highest p-values.
>
> My question: How can I use "update" when I have only the variable
name als
> string (e.g., "x1")? Or is there another convenient way to update
the
> model?
>
> Thanks!
>
> Sincerely,
> Denis
>
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