Hi, I have a quick question: I'm running a PGLS with many correlated traits and my co-author suggested to first apply PCA on the traits, then use the axes as predictors in my PGLS.
I was wondering whether I need to perform a phylo PCA or if a regular PCA would do the trick? My intuition is that pPCA would be better as it takes phylogeny into account, but again it isn't being estimated jointly with the rest of the PGLS model... Also, is there any theory as to how this will impact phylogenetic signal in the residuals of the model? For some reason it feels odd to take phylogeny into account twice... Max [[alternative HTML version deleted]] _______________________________________________ R-sig-phylo mailing list - R-sig-phylo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-phylo Searchable archive at http://www.mail-archive.com/r-sig-phylo@r-project.org/