Dear Tony! 
I am very glad that you have not forgotten our expedition, though it was
so for a long time ago! O-ho-ho-ho...
On my opinion - the fishing is a enough boring occupation. Studing of
the bone remains is much more interesting! Ha-Ha!
About your problem: 
I already collided with a problem of definition of the domestic horse on
an early stage of domestication. I consulted to my more experienced
colleagues and to archaeologists in that time. And I have come to a
conclusion, that it is very difficult to determine it on the basis of
statistical processing of measurements sotely. Besides, the reliability
of such results will be not so high. (I emphasize, that I speak it about
the practically same form in wild and earley domestic kind only.
Certainly, it is possible to distinguish the horse from onager or ass 
statistically without problems!). 
Some indirect attributes testify much more authentically about the
presence of the domestic horse on a settlement.
First  -  is a presence of some details of a horse harness among
archaeological artefacts. The harness has appeared ealy very much and 
cheeck-pieces, bronze bits and other bronze or bone details together
with it. Presence of only one(!) such find in an archaeological
material, already gives us an opportunity to speak about the domestic
form of a horse is present at the settlement.
Second - the appearance of bone remains of a horses. Not proportions,
but the general shape of it. The presence of bones with traces of
illnesses, of bones of obviously old animal, of characteristic wearing
of teeth from metal bits etc. By the way, last attribute speaks about
the horse was for a horseback riding mainly.
Look about it:

  Brown D., Anthony D.
Bit wear, horseback riding and the Botai Site in Kazakstan.
Journ. of Archaeol. Science. 1998. v.25,  n4,  pp.331-347.

And the third at last - age structure. You know not worse than me, that
if a bone collection is result of a hunt on wild herd - the age
structure will be standard, and if this is herd of the domestic animals
(especial if it is not a food resource, but  draught animals basically)
- age profil is absolutely another.

So, my opinion is that, to work with statistics not rationally in this
case. It is much easier to prove the presence (or absence!) domestic
horse at the ancient inhabitants such I have offered above. 
I very much would like to look your last papers (if I can to find out it
in our libraries!). 
I hope to be in touch with you further! 
                              Sincerely yours  Alexey.



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