simple predict question
On 5/31/05, sms13+ at pitt.edu <sms13+ at pitt.edu> wrote:
Excuse the simple question... I'm not sure what I'm doing wrong with predict, but let me use this example: Suppose I do: dat<-matrix(c(0,0,10,20),2,byrow=T) lm1<-lm(dat[,2]~dat[,1]) Suppose I want to generate the linearly-interpolated y-values between the point (0,0) and (0,20) at every unit interval. I thought I just do: predict(lm1, data.frame(seq(0,10,1))) to get 0,2,4,6...,18,20, but instead I just get: 1 2 0 20
I think the names are confusing it. Try: x <- dat[,1]; y <- dat[,2] lm1 <- lm(y ~ x) predict(lm1, data.frame(x = 1:10))