Look at Predict.Plot (and TkPredict) from the TeachingDemos package. -- Gregory (Greg) L. Snow Ph.D. Statistical Data Center Intermountain Healthcare greg.s...@imail.org 801.408.8111
> -----Original Message----- > From: r-help-boun...@r-project.org [mailto:r-help-boun...@r- > project.org] On Behalf Of Mark Na > Sent: Monday, November 15, 2010 2:40 PM > To: r-help@r-project.org > Subject: [R] How to plot effect of x1 while controlling for x2 > > Hello R-helpers, > > Please see a self-contained example below, in which I attempt to plot > the effect of x1 on y, while controlling for x2. > > Is there a function that does the same thing, without having to > specify that x2 should be held at its mean value? It works fine for > this simple example, but might be cumbersome if the model was more > complex (e.g., lots of x variables, and/or interactions). > > Many thanks, > > Mark > > > #make some random data > x1<-rnorm(100) > x2<-rnorm(100,2,1) > y<-0.75*x1+0.35*x2 > > #fit a model > model1<-lm(y~x1+x2) > > #predict the effect of x1 on y, while controlling for x2 > xv1<-seq(min(x1),max(x1),0.1) > yhat_x1<- > predict(model1,list(x1=xv1,x2=rep(mean(x2),length(xv1))),type="response > ") > > #plot the predicted values > plot(y~x1,xlim=c(min(x1),max(x1)), ylim=c(min(y),max(y))) > lines(xv1,yhat_x1) > > ______________________________________________ > 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.