Hi Noreen,

Semi-landmarks techniques would be the better approach here, as some of
the other replies have pointed out.

Another thing I should add is you can use a program called Resample
(http://nycep.org/nmg/programs.html) to resample your curves into a
user-prescribed set of evenly-spaced semi-landmarks, using weighted
linear interpolation. I think you were using the "auto-plot" option (at
4.0 mm) in the microscribe utility software when you were last at the
AMNH, and I remembered it was quite buggy. A new version (5.0) has come
out since then which fixed the auto-plot option, among other bits. If
you (or anyone else) need it, please let me know. For some odd reasons,
the updated utility program is not on the microscribe support website.

Steve Wang

NYCEP Morphometrics Group

[EMAIL PROTECTED]

-----Original Message-----
From: morphmet [mailto:[EMAIL PROTECTED]
Sent: Friday, February 02, 2007 11:51 AM
To: morphmet
Subject: Combining shape variables



Dear All



I have a question regarding combining two types of morphological variables

into the same analysis. I have a 3D landmark configuration and associated

3D outlines, which are registered in a common reference frame (via GPA). I

have generated Procrustes variables from the landmark configuration and

Fourier coefficients from the outline data.



A) Does anyone know of a published example where procrustes variables have

been analysed WITH Fourier coefficients in the same analysis (e.g.

Principal Components Analysis) and B) If not, can anyone think of any

reason why these two types of shape variables cannot be analysed

simultaneously? I ran a dummy test using both variables at the same time

and found that similar patterns between groups were produced with both

variable-types, although cross-validated classification of groups (using

Discriminant Function Analysis) was best when both Procrustes and Fourier

variables were used together.



Any further comments or suggestions would be greatly appreciated!



Many thanks in advance

Noreen

[EMAIL PROTECTED]



-- 

Noreen von Cramon-Taubadel

Department of Biological Anthropology

University of Cambridge

The Henry Wellcome building, Fitzwilliam street

Cambridge CB2 1QH

Phone: +44 1223 764719

[EMAIL PROTECTED]







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