On 14/09/2009, Steve Lianoglou <mailinglist.honey...@gmail.com> wrote: > Hi, > > On Sep 14, 2009, at 9:47 AM, e-letter wrote: > >> Readers, >> >> I have been reading the r book (Crawley) and tried to use the >> influence measures function for linear regression, as described. I >> have one datum that I wish to show in the graph but exclude from the >> regression and ab line. >> >> x y >> 0 5 >> 10 9 >> 20 10 >> 30 19 >> 40 4 >> >> With the influence measures function I plot the graph but linear >> regression includes the datum (40,4), which I want to show on the >> graph but exclude from the linear regression ab line. >> >> Is there an alternative package to perform this task please? > > Please post the code you're using to try and do the regression. > > I think you simply want to remove the data point when you build the > regression model, then plot it later after you plot the regression. > Correct; below are my commands:
x<-c(0,10,20,30) y<-c(5,9,12,19) fit<-lm(y~x) plot(y~x) abline(fit) I try these commands as explained in section 12 (graphics) of the introduction manual: points(40,4) plot(40,4,add=TRUE) Warning messages: 1: "add" is not a graphical parameter in: plot.window(xlim, ylim, log, asp, ...) 2: "add" is not a graphical parameter in: plot.xy(xy, type, pch, lty, col, bg, cex, lwd, ...) 3: "add" is not a graphical parameter in: axis(side, at, as.graphicsAnnot(labels), tick, line, pos, outer, 4: "add" is not a graphical parameter in: axis(side, at, as.graphicsAnnot(labels), tick, line, pos, outer, 5: "add" is not a graphical parameter in: box(which = which, lty = lty, ...) 6: "add" is not a graphical parameter in: title(main, sub, xlab, ylab, line, outer, ...) The datum is not added to the original graph. ______________________________________________ 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.
