-------- Original Message -------- Subject: Re: Thin plate spline Date: Thu, 15 Mar 2012 04:19:02 -0400 From: Øyvind Hammer <oyvind.ham...@nhm.uio.no> To: <morphmet@morphometrics.org> Good day, the module called thin-plate splines in Past is rarely used. It's just for showing the deformation from one single shape (or the average shape) to another single shape. Typically you instead use the PCA, regression or CVA modules which have their own thin-plate spline visualisation output. The colors (and the color scale bar) are only shown when you click "Expansion factors". They show what areas expand, and which areas shrink, using the "Jacobian" of the spline. When you click "Partial warps" you get those affine and non-affine components, bending energy, partial warp scores etc. I don't think many people are using partial warps anymore, at least not in isolation (people on the list correct me if I'm wrong), so this is mainly of historical/pedagogical interest. Maybe I will remove it. See also the Past manual, at http://folk.uio.no/ohammer/past Past - Because Your Data Deserve It (TM) Oyvind Hammer Natural History Museum University of Oslo On Wed, 14 Mar 2012 23:21:26 +0100, morphmet morphmet_modera...@morphometrics.org> wrote:
-------- Original Message -------- Subject: Thin plate spline Date: Wed, 14 Mar 2012 18:04:16 -0400 From: Ellen Baggao <ellenbag...@hotmail.com> To: <morphmet-requ...@morphometrics.org> Good day! We are using PAST (Paleontological Statistics) software for our study on shape analysis of the cone snails (/Conus sp.)/. My thesis partner and I are beginner in geometric morphometrics study and We are very confused on how to use the thin plate spline analysis in PAST. What do the various colors indicate for? How affine and amplitude component would affect the shape deformation when they are changed? What do the value of the bending energy for? Thank you and I am really hoping for your immediate response about this! God bless! -ellen
