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Archiver > GENEALOGY-DNA > 2007-02 > 1170346288


From: John Cartmell <>
Subject: Re: [DNA] New Ashkenazi DNA paper
Date: Thu, 01 Feb 2007 16:11:28 +0000 (GMT)
References: <BAY111-F256709C4DBE16782B6C1A0F1A50@phx.gbl><464006.61290.qm@web52103.mail.yahoo.com>
In-Reply-To: <464006.61290.qm@web52103.mail.yahoo.com>


On 01 Feb, ellen Levy <> wrote:
> According to Behar's Table 8, the K1a1b1a haplotype of 224,234, 311
> developed 1,755 years ago (I've never been able to read this table well.
> He also lists "SD" age at 877 years, whatever that means). He lists the
> haplotype 223, 224, 234, 311 at 3,313 years (or 1,506 years according to
> "SD"). Obvious, his dating verse that of "SD" makes a tremendous
> difference, so any assistance translating this table would be appreciated.

SD = Standard Deviation.

read as:

224, 234, 311 1,755 ya with a likely 'spread' of 877 years

means that, whilst the average comes out at 1,755 ya, you need to take into
account the possibility that the actual age is less or more - and (depending
on the certainty you require) you could express that as somewhere between
1,755+877 = 2,632 and 1,755-877 = 878 years ago.

Without expressing the certainty required you cannot express it as crudely as
I show the calculation - but be aware that SD indicates the likely spread of
the actual date around the calculated date. The smaller the SD the more likely
the actual date is going to be close to the calculated date.

--
John 006 8822 or 0161 969 9820
Qercus magazineFAX +44 (0)8700-519-527www.finnybank.com
Qercus - the best guide to RISC OS computing


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