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.