Dear morphometricians, 

Does a sample need to be normally distributed when conducting PCA in 
geometric morphometrics? Sometimes due to research constraints there are no 
samples of the opposite sex. Someone was asking me this question, and I do 
not have the answer. When I look at the data distribution, there is quite 
an imbalance male/female population. However, the classifiers male/female 
and species are there and you can sort of tell which group belongs to 
where. My only fear is that the confidence ellipse for the males are being 
"gravitated" towards the females for one species as that species does not 
have any male specimens. Attached are the file which I have recreated the 
dataset based on memory. 

Is this kind of data acceptable or publishable? 

My own personal question is based on the GMM results given in MorphoJ. The 
PC1/PC2 axes does not intersect at the middle (which I have personally 
drawn the dotted line there). I don't mind this output, but does it matter 
to have the axes cut at the 0 value? The data data distribution does not 
change with the change of axes lines. I noticed some GMM papers have the 
axes at 0. 

Thanks all for the help,

Helmi Hadi,
School of Health Scienes, 
Universiti Sains Malaysia

MORPHMET may be accessed via its webpage at
You received this message because you are subscribed to the Google Groups 
"MORPHMET" group.
To unsubscribe from this group and stop receiving emails from it, send an email 

Reply via email to