You are using fitted() implicitly here, so you are not plotting a smooth curve but a set of fitted values.
You need to really predict at a suitable range of data points, e.g. xx <- seq(1, 10, len=500) plot(xx, predict(w, list(x=xx)), type="l") BTW, why are you not using poly()? On Tue, 31 Jul 2007, Wilson, Andrew wrote: > Probably a very simple query: > > When I try to plot a curve from a fitted polynomial, it comes out rather > jagged, not smooth like fitted curves in other stats software. Is there > a way of getting a smooth curve in R? > > What I'm doing at the moment (for the sake of example) is: > >> x <- c(1,2,3,4,5,6,7,8,9,10) > >> y <- c(10,9,8,7,6,6.5,7,8,9,10) > >> b <- data.frame(cbind(x,y)) > >> w <- gls(y ~ I(x)+I(x^2),correlation=corARMA(p=1),method="ML",data=b) > >> plot(predict(w),type="l") > > Many thanks, > > Andrew Wilson > > ______________________________________________ > R-help@stat.math.ethz.ch 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. > -- Brian D. Ripley, [EMAIL PROTECTED] Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/ University of Oxford, Tel: +44 1865 272861 (self) 1 South Parks Road, +44 1865 272866 (PA) Oxford OX1 3TG, UK Fax: +44 1865 272595 ______________________________________________ R-help@stat.math.ethz.ch 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.