Hi Will,
I think you meant to say that you are writing a study design paper
presenting results of simulations and power analysis to determine
appropriate sample sizes for multivariate analyses in geometric
morphometrics. But I would think that would have already been settled by
now, and possibly w
In discussions like these it would be helpful if the writer could clarify
whether they are referring to the concepts of biological homology, topological
homology or "semantic homology". These aren't the same things and the whole
issue of “homology” in geometric morphometrics has always seemed, a
Hi Philipp,
I am not worried about the number of variables (although I am not sure
one needs thousands of highly correlated points on a relatively simple
structure and seem to remember that Gunz and you suggest to start with
many and then reduce as appropriate).
Regardless of whether point homolog
Hello,
I'm an archaeologist who works on artifacts in North America. There are not
many of us that use LGM, but even we can't seem to agree on how many LMs
are appropriate. Because I use discriminant function analysis as the
workhorse for discriminating groups of artifacts, I worry about the misuse
I think a few topics get mixed up here.
Of course, a sample can be too small to be representative (as in Andrea's
example), and one should think carefully about the measures to take. It is
also clear that an increase in sample size reduces standard errors of
statistical estimates, including tha
populations, or historical collections.
M
From: William Gelnaw [mailto:wgel...@gmail.com]
Sent: Wednesday, May 31, 2017 3:41 PM
To: mitte...@univie.ac.at
Cc: MORPHMET
Subject: Re: [MORPHMET] Re: number of landmarks and sample size
I'm currently working on a paper that deals with the problem of
Gelnaw [mailto:wgel...@gmail.com]
Sent: Wednesday, May 31, 2017 5:41 PM
To: mitte...@univie.ac.at
Cc: MORPHMET
Subject: Re: [MORPHMET] Re: number of landmarks and sample size
I'm currently working on a paper that deals with the problem of
over-parameterizing PCA in morphometrics. The reco
I'm currently working on a paper that deals with the problem of
over-parameterizing PCA in morphometrics. The recommendations that I'm
making in the paper are that you should try to have at least 3 times as
many samples as variables. That means that if you have 10 2D landmarks,
you should have at
Dear All,
I'd like to add a few comments on sampling (landmarks but also
specimens). I hope that some of the other subscribers, who know much
more than I do about morphometrics, will refine and correct my points.
A very short one on my two papers. They make a very simple point: if one
is lan