Angela, Why not include all of the specimens "undetermined" and "specified" in a single Procrustes analysis and the look at the distribution of datapoints in morphospace?
How many individuals do you have in your "reference" or "specified" sample? What is the criterion used for establishing these specimens as the "reference"? If this is purely subjective, then do not expect your results to be objective. Be careful with purely verbal or descriptive assessments of diagnostic characters, try to always use a quantifiable approach. If you have statistical parameters for two or more groups or classes for which enough independent evidence is available to support their existence as real entities, then you could probably use discriminant functions to assess the distance between your "undetermined individuals" and these groups. If you have just one reference group, then looking at Mahalanobis or procrustes distances in morphospace will provide an idea of the distances between groups, samples and overall variability. I am sure there are descriptions for more formal applications of this problem somewhere in the literature ocean. Pablo Pablo Jarrin Ph. D. grad student Department of Biology Boston University -----Original Message----- From: morphmet [mailto:[EMAIL PROTECTED] Sent: Thursday, March 08, 2007 10:23 AM To: morphmet Subject: tpsSplin usage Dear morphometricians, at present I'm working on some lepidopteran sibling species. Being very difficult to identify these species not only by external features but also by genitalia, I want analize (and quantify) the shape variation of some anatomical parts. I'm asking for help about the better method to compare individuals. I have to compare a sample of (many) undetermined individuals to some specified specimens (typical specimens). Could I employ tpsSplin software to analyse my data? I would use my typical specimens as reference instead of computing it. Is it allowable to make such comparison? I would also know if there is a value that I can employ to quantify the variation among my reference-specimens and the set of data. In the report three values are computed for each specimen. I'm thinking to use only d (Procrustes Distances), or it is better use the three values together (i.e., Bending Energy, Procrustes Distance and angle)? Thank you very much for any suggestion. Angela Roggero -- Dott. Angela Roggero Dpt. Biologia Animale Via Accademia Albertina 13 I-10123 Torino - ITALY Phone +39 011 670 4536 Fax +39 011 236 4536 www.personalweb.unito.it/angela.roggero/ -- 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
