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View Full Version : FYI: FTDNA has unexpectedly changed it's TiP tool...again



MitchellSince1893
08-13-2016, 08:29 PM
A few years ago, FTDNA temporarily did something to change the results of the TiP function, resulting in much higher percentages...after a few weeks it reverted back to the old values.

The percentages are the probability that your match and you shared a common ancestor within the last 1-24 generations


Apparently something has recently changed in the last week, because the percentages are again higher.

A comparison of my closest match's New and Old values
Gen. New Old
1 0.01% 0.00%
2 0.19% 0.00%
3 1.01% 0.00%
4 3.06% 0.01%
5 6.79% 0.04%
6 12.33% 0.15%
7 19.47% 0.40%
8 27.77% 0.93%
9 36.68% 1.87%
10 45.70% 3.37%
11 54.36% 5.53%
12 62.34% 8.46%
13 69.46% 12.17%
14 75.61% 16.63%
15 80.80% 21.75%
16 85.09% 27.41%
17 88.55% 33.44%
18 91.31% 39.67%
19 93.46% 45.93%
20 95.13% 52.08%
21 96.41% 57.99%
22 97.37% 63.54%
23 98.09% 68.67%
24 98.62% 73.34%

So at 24 generations there was a 73.34% chance this match and me shared a common ancestor. Now it's changed to 98.62%. FYI: YFull estimates our shared ancestor lived 1000 years before present (1950 AD). Assuming 30 years per generation, that works out to 33 generations to the shared ancestor.

This unannounced change (I couldn't find an announcement) caused me to contact a new match that came in at 84% at 24 generations...or over 10% higher than my closest match's old results above, but 14% below the new value.

If I had been informed of the change I wouldn't have bothered to contact him.

Saetro
08-14-2016, 08:46 PM
Apparently something has recently changed in the last week, because the percentages are again higher.

This unannounced change (I couldn't find an announcement) caused me to contact a new match that came in at 84% at 24 generations...or over 10% higher than my closest match's old results above, but 14% below the new value.

If I had been informed of the change I wouldn't have bothered to contact him.
Have you asked them?

MitchellSince1893
08-15-2016, 03:05 AM
Have you asked them?

Now that I'm aware of the change there's no point. A heads up would have been nice though.

vettor
08-17-2016, 07:35 AM
What does the bolded surnames indicate in the FF in the new ftdna tool-tip?

vettor
08-20-2016, 06:17 PM
What does the bolded surnames indicate in the FF in the new ftdna tool-tip?

I found out that the bolded surname of ancestors in FF ( Ftdna ) = Surnames which match in both yours and theirs family tree reflecting your personal line

for me .............I have no Bartolomeo Cemin 1801 from Siror, Trentino, Italy ...............I do not have a Cemin in my 8000 surname trees ( mine or others )