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  • #16
    Originally posted by Jim Barrett View Post
    Have you compared the marker values for A & B to yourself on Ysearch to get an idea of the genetic distance?
    yes, in ftdna its 0 , in ysearch its 15

    Have you compared the marker values for A & B to yourself on a FTDNA site to get an idea of the genetic distance?
    see above

    Do the marker values between FTDNA and Ysearch agree for all three of you?
    no

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    • #17
      Originally posted by tommypeters View Post
      I believe FTDNA use a "modified step method", meaning that if two persons have 20 and 23 as you write it depends on the STR how much this difference will contribute to GD. If it's a very unstable STR that has very fluctuating values from generation to generation at least they should only "rate" that difference as 1 when adding GD. If it's a marker that usually keeps its value from generation to generation and mutations are unfrequent, 3 should be added to GD.

      I haven't read any official statement from FTDNA if they use this method or not, only second-/third-hand info that it is how they calculate.
      So, would the "red" marked DYS in the projects which represent the fast mutating ones get a different rating?.... and due to this fast mutating , ftdna treat it as a infinite GD instead of a step GD?

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      • #18
        Originally posted by Táltos View Post
        thanks

        the link does not show which method they use.

        I would like to see what ftdna calculate for only 1 different STR which is more than 1 point in difference.

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        • #19
          Originally posted by Bartot View Post
          I would like to see what ftdna calculate for only 1 different STR which is more than 1 point in difference.
          I can see, on Y-DNA Genetic Distance in my project, that they are using the differences in STR values.

          I have verified that using abacus and Y-DNA Results Colorized page. That worked for genetic distances of up to 25. My members have done Y-67 tests and the maximum difference in STR values on one of the hot markers was 4.

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          • #20
            Here is an example of two GD 5s. The probability calculations at the listed generations are different due to mutation rates of the different markers involved in each of the 5 mismatches. Note Kit # 34795 is involved in each case and the Distantance numbers are integers.

            In comparing Y-DNA111 markers, which show 5 mismatches, the probability that (34795) and (299153) shared a common ancestor within the last...

            ...4 generations is 12.40%.
            ...8 generations is 61.13%.
            ...12 generations is 90.48%.
            ...16 generations is 98.38%.
            ...20 generations is 99.78%.
            ...24 generations is 99.97%.

            In comparing Y-DNA111 markers, which show 5 mismatches, the probability that (34795) and (242728) shared a common ancestor within the last...

            ...4 generations is 11.98%.
            ...8 generations is 60.14%.
            ...12 generations is 89.96%.
            ...16 generations is 98.24%.
            ...20 generations is 99.76%.
            ...24 generations is 99.97%.

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            • #21
              Originally posted by Bartot View Post
              I will try to make it clearer.

              Me and person A ...........both have done 67 marker test.
              In ftdna we are 0 GD
              In ysearch we are 15 GD

              me and person B ........B only tested to 37 markers.
              In ftdna we are 0 GD
              In ysearch we are 5 GD

              we have a problem,

              Clearly ftdna do not indicate and ignore my 67 to 67 , 37 to 37, 25 to 25 with matching test with me and person A ......why? ........it is a false reading of zero GD .
              We understand your question, and it has been answered. FTDNA does not display very distant matches, because they are not genealogically relevant. ysearch lets you see them, but they still are not genealogically relevant.

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              • #22
                Option

                I didn't read all the post and this might have been mentioned. There are option we have to check. I found a match at Ysearch who tested here. He doesn't show up on the 12, 25, 37 marker level but does show up at 67. I had only tested to 37 when I found him at Ysearch. He shared the same last name as all my matches so I wondered why he did not show up. I wondered if I tested to 67 would he show up as a match and he did.

                Its been awhile since I did the test but I think I remember option like show only people who share the same last name and or who have tested to what ever level you want them to.

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                • #23
                  Originally posted by susan_dakin View Post
                  We understand your question, and it has been answered. FTDNA does not display very distant matches, because they are not genealogically relevant. ysearch lets you see them, but they still are not genealogically relevant.
                  Well , isn't that the question. I've seen an example of a GD of 5 (@37) of people with the same ancestor from 1569. This one won't show in the match list on FTDNA.

                  On the other hand: the Family Finder autosomal match list shows results that are far more speculative.

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                  • #24
                    FTDNA Entered Data Loss

                    Re-posted this Thread per dna's suggestion

                    Is there any way to save the 'data' entered online, (Profile, Stories, Notes, and Images, etc.) prior to a Gedcom update/overwrite?

                    If ALL is LOST, then that WOULD be a SEVERE deterrent to doing anything online with the FTDNA Tree, except upload and look.

                    Unless we could export from the FTDNA Tree, as a Gedcom, or Data file, WITH all of the additions.

                    John K -- Batch 586 BigY results RECIEVED 09 OCT 2014, Awaiting access to my BAM Raw Data. Case {180973}

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