Hi
Bert Gunter <gunter.ber...@gene.com> napsal dne 14.04.2010 18:01:52: > Below. > > -- Bert > > > Bert Gunter > Genentech Nonclinical Statistics > > > Coefficients are different as you fit different values. See > > ?poly > > poly(-10:10,2) > > I believe that others give you better explanation. So you can not use > coefficients evaluated by lm(.~poly(...)) directly. > > -- Well, it depends what you mean by "use...directly." But I think the I mean that you can use fit<- lm(y~x+I(x^2)) coef(fit)[1] + coef(fit)[2]*x + coef(fit)[3]*x^2 but you can not use fit<- lm(y~poly(x,2)) coef(fit)[1] + coef(fit)[2]*x + coef(fit)[3]*x^2 to compute y. Regards Petr > answer is, "yes you can." See ?SafePrediction for details. -- Bert > > Regards > Petr > > > > > Thanks in advance, > > Stefan > > > > ______________________________________________ > > 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. > ______________________________________________ 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.
