Christoph Lehmann
2003-Jun-06 14:07 UTC
[R] understanding LDA: normalization of the eigenvectors
Hi dear R-users I try to reproduce the steps included in a LDA. In my textbook (Bortz) it says, that the matrix with the eigenvectors V usually are not normalized to the length of 1, but in the way that the following holds (SPSS does the same thing): t(Vstar)%*%Derror%*%Vstar = I where Vstar are the normalized eigenvectors. Derror is an "error" or "within" squaresum- and crossproduct matrix (squaresum of the p variables on the diagonale, and the non-diagonal elements are the sum of the crossproducts). For Derror the following holds: Dtotal = Dtreat + Derror. Since I assume that many of you are familiar with this transformation: can anybody of you tell me, how to conduct this transformation in R? Would be very nice. Thanks a lot Cheers Christoph -- Christoph Lehmann <christoph.lehmann at gmx.ch>