This recomputes the lm but if that is ok then: mod <- lm(y1 ~ x1 + x2 + x3 + x4, anscombe)
mod$call$formula <- update(as.formula(mod$call$formula), ~ . - x1 - x2) predict(eval(mod$call), list(x3 = 1, x4 = 1)) On Tue, Jan 19, 2010 at 11:10 AM, Werner W. <pensterfuz...@yahoo.de> wrote: > Hi, > > probably just a quick question: can I somehow change the formula used with > predict? E.g., the regression was run on "y ~ u + v + w" but for the > prediction the term v should be removed from the formula contained in the > regression object and only "y ~ u + w" be used. > > I could use model.matrix etc. to do the predictions but it would be very > helpful to know a simpler way. > > Thanks so much, > Werner > > > __________________________ > verfügt über einen herausragenden Schutz gegen Massenmails. > http://mail.yahoo.com > > ______________________________________________ > 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.
