I perform PLS with pls package in R using
Why am I unable to get the same predicted Y value as when I use the
predict function as when I dot product the regression coefficients with the test data. I have read from other answers that I should be able to do this, especially if the method is set to
I did some further testing and it seems like there is a bias/intercept constant that I have not added in. However, from elsewhere I read that with mean centering, the intercept should be 0 and I believe
plsr has already mean centered all my data by default. I am wondering why is there still an intercept and also how can I find this intercept constant from the
I have found the
coef(,intercept=TRUE) function! However, my question still remains, why is there an intercept when my data has been mean centered (Both X and Y)?
Many thanks for your help!! Let me know if I can clarify anything at all!