From: G6JPG-255@255soft.uk
In message , Ian
Goddard writes:
>On 23/04/19 20:19, Athel Cornish-Bowden wrote:
>> On 2019-04-23 17:40:19 +0000, Ian Goddard said:
>> It's not my "sweeping statement". Everyone familiar with population
>>genetics agrees that when enough time has passed either everyone
>>living is descended from a particular person (with, as I said,
>>exceptions for recent immigrants from distant places),
[]
>> or no one is. In the case of William I the "no one is" option is
>>sufficiently unlikely to be set aside.
>
>Or no one? Really. We know that there are some traceable descendants
>of William I so is this supposed to prove that on some statistical
>assumption that everyone is?
I suspect that's just taking account of cases where a certain person had
no children. (Or, less so, Oliver Cromwell having no male ones, so
anyone _with the surname Cromwell_ claiming descent from him - unless
they can _show_ their working - is suspicious.)
>
>>> that we're all descended from William I the only way in which this
>>>would be supportable would be to trace everyone's ancestry back to
>>>the C11th.
>> That's not how it's done. It's a matter of statistical analysis.
>>
>
>There are a couple of comments on that. The first is that statistics
>deals with probabilities. You're claiming certainty, not probability.
It's allied to entropy. I once saw an animation (part of physics on the
OU, or something like that) of a brick being dropped onto flat ground;
the energy of the impact travelled outward in the movements of the
molecules in the ground. The commentary explained that the random
movements of molecules could, in theory, just happen to converge in such
a way that the process could be reversed, _without_ breaking any of the
laws of physics: nevertheless, bricks lying on the ground do _not_
spontaneously leap into the air. Statistics and probability do work such
that when something is sufficiently likely or unlikely, then for
_practical_ purposes, it will or won't happen.
(I agree with you that the Bill Conc hypotheses aren't at that level of
certainty yet - though my _feeling_ is that
we're_*mostly*_descended_from_him [or anyone else, certainly of the
ruling class of that time] _is_ likely to be true. Certainly, 2^4x well
exceeds the population of the country then [and the planet, by a huge
extent]: 2^20 is around a million. [So the _present_ population of the
planet is "only" about 2^36.])
>
>Secondly, a given statistical analysis assumes a particular model.
>AFAICS your analysis depends on lack of mating. Geography provides
>restraints as does social stratification. Not complete restrains,
>granted, but restraints. What evidence is there for these restraints
>being insufficient to be negligible in the time-frame?
I agree that they counter the simple progression hypotheses. But it is a
big step from saying they account for only a tiny proportion of births,
to saying that such births eventually "breed out" (i. e. disappear); on
the contrary, provided such genes survive two or three generations (I
can see that "the squire's bastard" might not find a wife [though might
still do some fathering!] - but if he does, I don't think the taint
would survive much beyond a couple of generations), they should
propagate like any other.
>
>You're stating a hypotheses. What test do you propose for such a
>hypothesis?
You're stating the obvious counter-hypothesis. What test ... (-:
--
J. P. Gilliver. UMRA: 1960/<1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf
And every day in Britain, 33 properties are sold for around that price [a
million pounds or so]. - Jane Rackham, RT 2015/4/11-17
--- SoupGate-Win32 v1.05
* Origin: you cannot sedate... all the things you hate (1:229/2)
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