Please read the posting guide (requires a self-contained example of code) and consult the help pages before posting. If you type ?predict.lm the help page clearly states that the argument 'newdata' takes "[a]n optional data frame in which to look for variables with which to predict..."
x1<-rnorm(100) x2<-rnorm(100) e<-rnorm(100) y<-x1+x2+x1*x2+e reg<-lm(y~x1*x2) summary(reg) predict(reg,newdata=data.frame(x1=2,x2=2)) HTH, Daniel halptekin wrote: > > Here is my model with interaction terms and control variables (I changed > variables names for easy read): > > reg1 <- lm(y ~ x1*x2*x3 +control1 + control2 + control3) > > x1 ranges from 0 to 6; x2 from 0 to 5; and x3 from 0 to 4. All three are > discrete ordinal variables; but I will treat them as continuous variables. > (a) How can I see the predicted values of y for each of these scenarios > (210 y values I guess)? > (b) How can I see the predicted value of y for the minimum and maximum > values of x1, x2, and x3 (8 y values)? > (c) How can I see the predicted value of y for x1=6; x2=5; and x3=4 (only > one y value)? > -- View this message in context: http://r.789695.n4.nabble.com/How-to-get-predicted-values-of-y-for-different-x-values-tp3678658p3679351.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ 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.