I'm a bit late in jumping on the repeatability bandwagon, but for what
it's worth, regarding semilandmarks, allow me to throw in my ten cents'
worth.

Their initial positions along the outline are arbitrary, but I assume
one could probably derive new coordinates for them after having "slid"
them in TPSRelw, and then treat them as true landmarks for the purposes
of repeatability.

If one felt compelled to do so.

That would, however, not be statistically valid since their final
positions will be determined by the positions of those terminal
landmarks which anchor them.

Repeatability of the semilandmarks will therefore be related to
repeatability of the terminal landmarks, and my personal feeling is to
not worry about the semilandmarks too much, but take very special care
in minimising digitising error in terminal landmarks.

> Lets see, take a x number of individuals, make three repeated 
> measurements, preferably by different people, and estimate the 
> proportion of the variation that is explained by individual versus all
> the available variation. Either landmark by landmakr, of all at once
in 
> a MANOVA. 
> 
> For semi landmarks, no idea, never worked with those. 
> 
> Good luck. 
> 
> Kim 
> 
> morphmet wrote: 
> 
>> I was simply wondering what would be the best way, the most
appropriate 
>> statistical test, to evaluate the repeatability of your landmark 
>> placement. 
>> 
>> Furthermore, would this method also work with semi-landmarks? 
>> 
>> 
>> Thanks 
>> 
>> Martin 
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> For more information visit http://www.morphometrics.org 
> 
> 





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