GENEALOGY-DNA-L ArchivesArchiver > GENEALOGY-DNA > 2010-02 > 1265562343
From: Al Aburto <>
Subject: Re: [DNA] Intraclade Age Sigma "Unknowable"
Date: Sun, 07 Feb 2010 09:07:31 -0800
References: <009601caa80d$da9ca2a0$5e82af48@Ken1> <4B6EEA3B.firstname.lastname@example.org><000601caa813$70017870$5e82af48@Ken1>
From your postings and emails I have quit on the intraclade estimation
a while back. I been using the TMRCA pairs estimation instead as I
could not quite come to grips with what the interclade estimation was
doing for me. It gives an age between two groups, but not of one ...
I appreciate your efforts very much! Slowly I'm coming around to
understanding things more fully.
> On 2/7/2010 8:34 AM, Ken Nordtvedt wrote:
> Doing TMRCA for a pair of haplotypes is doing an INTERCLADE age estimate.
> Look at your tree. There is no demographic uncertainty; there is only the
> tree depth uncertainty which you will estimate.
> You don't need intraclade confidence intervals if you quit doing intraclade
> age estimates. Reformulate what you want to learn in terms of a collection
> of interclade age estimates.
> ----- Original Message -----
> From: "Al Aburto"<>
> Sent: Sunday, February 07, 2010 9:28 AM
> Subject: Re: [DNA] Intraclade Age Sigma "Unknowable"
>> We sure do need a sigma though. We have the data ... attached to it
>> there is indeed a sigma, but you are saying it is unknowable from
>> current haplotypes.
>> I have tried doing TMRCA estimates in pairs of (unique) haplotypes
>> (using Walsh's infinite allele method) on a group of "n" haplotypes and
>> then getting the mean and sigma from that for the group (cluster) of "n"
>> haplotypes. Is this meaningful?