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From: "Dienekes Pontikos" <>
Subject: Re: [DNA] The new J2 Cohen-Levi Modal Haplotype (so-called)
Date: Tue, 1 May 2007 12:13:02 -0700
References: <463404D5.3050204@comcast.net><f3f05ce80704301313l14e17462ob2a95805c3be592@mail.gmail.com><46367FC2.2090201@ucl.ac.uk><f3f05ce80705010233o271736e5x3cdaef0f9cbbc77c@mail.gmail.com><46373378.1080407@ucl.ac.uk>
In-Reply-To: <46373378.1080407@ucl.ac.uk>


Dear James,

I will restate my objection with an analogy to make it clearer.
Suppose we have two groups, BLUES and GREENS, and it is proposed that
most (or more than x%) of both drive the same car model (let's call
this event X).

The original papers showed that they both drive Japanese cars (=CMH-6)
to a great degree, and this was interpreted as evidence in favor of
event X, since we erroneously assumed that "Japanese" is a car model
and not a country.

Certainly, the original papers had the power to reject X, if it e.g.,
turned out that one group drove Japanese cars and the other one French
ones. But, it did not have the power to confirm X, since the
assumption that "Japanese" was a car model (=genealogical link) was
false.

Later it was discovered that Japanese cars come in two varieties (=J1
and J2), say Toyotas and Hondas. And, of course, there are many
different models of Toyotas and Hondas, say Camrys/Corollas and
Civics/Accords.

We then discovered that many BLUES drive Toyota Corollas (=J1/CMH-12).
Actually we don't know that most of them do, which reduces our
confidence even further, but let's assume for simplicity that all of
them drive Toyota Corollas. What can we say about the probability of
event X?

Well, GREENS could still drive Toyota Corollas/Camrys or Honda
Civics/Accords. Event X is true only if they drive Toyota Corollas, or
let's say 25% of the time. Thus, event X, that they drive the same car
model is still not demonstrated convincingly.

What I am proposing is to get samples of GREENS and BLUES and see what
they are driving. If it turns out that 75% of GREENS drive Toyota
Corollas and 65% of BLUES drive Toyota Corollas, then event X will be
supported. If it turns out that 75% of GREENS drive Toyota Corollas
and say 85% of BLUES drive Honda Civics, then event X will be
rejected.


--

Dienekes' Anthropology Blog
http://dienekes.blogspot.com

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