The "partial warp scores matrix" = the "W matrix". The "Relative warps score matrix" gives the results of a PCA of the W matrix. Note that there is an option for whether or not the uniform shape component is included (the default) or not.
One will get the identical discrimination between groups whether one uses the W matrix of the relative warp scores. The choice depends on whether you want the partial warps or the relative warps to be the variables. ----------------------- F. James Rohlf, Distinguished Professor & Graduate Program Director State University of New York, Stony Brook, NY 11794-5245 www: http://life.bio.sunysb.edu/ee/rohlf > -----Original Message----- > From: morphmet [mailto:[EMAIL PROTECTED] > Sent: Thursday, May 26, 2005 8:07 AM > To: morphmet > Subject: Morphometric analysis > > [Oops, found a couple of postings I missed. No excuses. > -Moderator (a.k.a. dslice)] > > I'm a first year Ph.D student in the Ecology and Evolution > Department at Leeds University, England. I'm studying a > cline in morphotype in the inter tidal snail Littorina > saxatilis which suggests there may be speciation in progress. > I am very interested in using geometric morphometrics to > quantify the variation in shell shape of the snails, although > my knowledge of the field is limited at this stage. > > I have sampled L.saxatilis from five locations along a > vertical transect of the shore. I wish to analyse the cline > in morphotype by analysing shell shape variation between the > five locations along the transect containing hopefully three > morphotypes (H, I and M). I have also sampled from a second > transect to replicate the experiment. > > I have taken the route of landmarks and I am using the > software TPS. I plan to use PCA/DFA in an attempt to > discriminate between the morphotypes. However, I am unsure > whether to use the Partial warp scores matrix, Relative warps > score matrix or Weight matrix from the TPSRelw program in the > analysis. > > I would be grateful for any advice. > > Catherine Sinfield > > [EMAIL PROTECTED] > > > > > > ______________________________________________________________ > __________ > Yahoo! Mail Mobile > Take Yahoo! Mail with you! Check email on your mobile phone. > -- > Replies will be sent to the list. > For more information visit http://www.morphometrics.org > -- Replies will be sent to the list. For more information visit http://www.morphometrics.org
