Archiver > GENEALOGY-DNA > 2005-05 > 1116954921

From: (John Chandler)
Subject: Re: [DNA] DAR, SAR, UELA and DNA
Date: Tue, 24 May 2005 13:15:21 -0400 (EDT)
References: <>
In-Reply-To: <>(message from Jim Bartlett on Tue, 24 May 2005 09:18:54 -0400(GMT-04:00))

Jim wrote:
> John - I think the pool should be much larger. Hypothetically half
> the children of an early ancestor are female and marry new (usually)
> surnames...

The relative sizes depend on the eligibility rules. While many, if
not most, heritage societies allow any descent, the Founders and
Patriots have a complicated set of eligibility rules. The members
have to be male, and their lines of descent have to be *mostly*
male, but a certain number of exceptions are allowed for females
in the latest few generations. The bottom line is that a candidate
can claim eligibility on the basis of any of five of his eight ggp's,
but the other three are "unworthy". Obviously, one of the five
ggp's is the all-male line, and the other four are not. Hence, my
assertion that the total pool is five times the size of the
male-only pool.

For the SAR, the ratio is something like two raised to the seventh
power (seven being the approximate number of generations elapsed
since the seminal event). Needless to say, male-only lines are
completely absent for the DAR, since the members are in fact female.

> It makes you think, hard,
> about what your genealogical objectives really are - 118,800
> searches, all with different surnames than BARTLETT is pretty
> daunting...

Indeed it does. The one family association that I have joined has
a founder who was born c1594. I estimate that he has 10 million
living descendants. We are compiling a database that has now grown
past 120,000 persons. Let's see, at the rate of 20,000 persons per
year, we should be finished in about... -gulp- 500 years. By then,
of course, we expect almost everybody in the world to be a descendant,
and so the compiling will be a lot easier. (And if the association
membership remains the same fraction of the total pool of descendants,
our income from dues will be truly astronomical!)

> Does anyone have an estimate of the number of cousins who married,
> and how, statistically, that might reduce the 200,000+ individuals
> in the one family above?

Here are some statistics from the 120,000-member database, by
generation from the founder. These are the fraction of marriages
among his descendants where both spouses were known to be his

3 - 0.029
4 - 0.067
5 - 0.057
6 - 0.079
7 - 0.070
8 - 0.057

I think that's about where the database becomes too spotty to be
useful. My guess is that the true fraction would continue to
rise, if only we could follow all the "lost" lines.

John Chandler

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