Archiver > GENEALOGY-DNA > 2011-03 > 1300402977

From: Mike W <>
Subject: Re: [DNA] NPE rate
Date: Thu, 17 Mar 2011 18:02:57 -0500
References: <><>
In-Reply-To: <>

I've been using 3.9% expected NPE rate per generation based on this ISOGG
article and the study cited that is an evaluation of a large number of other

Is this 3.9% a decent rate to use?

----- The ISOGG article says:
"One review, published in April 2004 paper by Professor Kenneth Anderson,
University of Oklahoma, reviewed and studied 66 published studies on the per
of non-paternal events in father-son tests.....

The non-paternity rates for the 3 groups were 1.9%, 3.9%, and 30.9%. Fathers
with high paternity confidence seem to be correct in assessing
non-paternity, the
1.9% rate. “High and unknown” levels of paternity confidence exhibited the
3.9% rate. Those who didn’t know, e.g., low paternity confidence, had the
highest non-paternity rate, n.b. 30.9%.

For the purposes of this discussion I have concluded that the 3.9%, rounded
to 4% per generation is at least representative of what we could expect. All
non-paternal rates are highly idiosyncratic, depending on location, time,
religion and other factors. But remember that a 4% non-paternality rate
could be
made up of about 2% illegitimacy and 2% other causes. "

---------- A.J. Levin wrote:

Is this an "NPE rate" or an aggregate NPE/bad-genealogy rate?

I suspect the latter based on the number of false and absurd trees I have
seen. Your rate is nearly three times higher than the median number that the
classic peer-reviewed article on the subject found:

---------------------- Diana Gale Matthiesen wrote:
To: <>

The NPE rate in my surname projects is running close to 10%, so I'm quick to
suspect one when you have a 66/67 match outside your surname.

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