You obviously don't understand the mathematics of Joint Probabilities.
If the probability of an FPE is p = .02 [2%] in each generation of a descent
then the probability that the Paternal Descent is NOT false is p = .98.
Then calculating the JOINT Probability of True Paternal Descents over 50
generations gives us:
..98^50 = .3642.
Therefore the p for FPE over the 50 generations is:
1.0000 - .3642 = .6358 or about 64%.
However, using the 5% figure for FPE's we get a p of .9231 or 92%.
DSH
Lux et Veritas et Libertas
<j.s.plant@isc.keele.ac.uk> wrote in message
news:mailman.186.1186245752.31452.gen-medieval@rootsweb.com...
On Aug 2, 1:31 am, John Plant <j.s.pl...@isc.keele.ac.uk> wrote:
taf wrote:
Apart from a couple, whose male lines both originated in south
Lincolnshire around 1800, these 9 have random haplotypes. This is
consistent with expectation for a surname that originated from a single
ancestor, since, in the centuries since then, about half of the lines
are expected to have a false paternity event (FPE) somewhere in the line
of descent (unfaithful wife, adoption, unmarried mother giving child her
own surname, etc). This phenomenon of FPEs is widely documented in
DNA-genealogy literature.
The phenomenon has been widely discussed, but not widely documented.
To document it, you actually have to show that people who 'should'
have the same ancestor don't have the same type. All too often, though
this is assumed rather than documented. Are any of yours documented
FPEs?
taf
True. Let's see some documented FPE's as noted.
[...]
Perhaps you already knew all this; but most people as yet seem to get
confused.
John