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smithsworldwide (Admin)
FAQ: How Do I Compare YDNA Markers on the Smith DNA Project?

Posted by smithsworldwide in Smith DNA on June 4, 2014 Views:(127Replies (0)
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There are 2 places you can compare markers. One is on the FamilyTreeDNA website, after logging on using the credentials FamilyTreeDNA sent you when you joined. Depending on which type of match you are looking for, you can go to mtDNA/FamilyFinder or YDNA matches. For YDNA matches, you can either look at the entire database for matches or choose to look within projects you have joined. Likewise, if you would like to *filter* your results so that you only see the ones that have the surname Smith, you can. FamilyTreeDNA will send you out an email when you have some type of match in their entire set of members. That may or may not be the Smith surname, your results might include a lot of people from all over the map with various surnames. You can contact the people from this matching screen at FTDNA if the person has decided to show his or her email.
For the Smith Official DNA project, we also have matching on the site. When we are informed by FTDNA that results are in, we put them up on the site, where we have some custom reports. You can see the comparison report on the page on the Smith site where your kit is. You can find that kit from most pages by doing a search for it. You can also find it on reports where kits are listed. The icon for it looks like this.  The comparison report is a conservative report that compares people within the Smith project on the site-that can also include members who tested with vendors other than FTDNA. The comparison is always done using FTDNA’s methodology and uses the haplogroup as the common identifier to sort kits by (So, if you are an R1b, you will not be compared against I2b) . Here is an example of the comparison report that compares against the haplogroup, ie, EVERYONE who has a haplogroup like this at Smiths. You can see how a kit compares and to what extent. Kits that don’t match at all are left off this report.

If a member has been matched into a group. there will also be two more reports, one a modal group report and one a comparison group report. The first looks within the group and finds the *modal* for each value, creates a modal baseline and then compares the kits against that baseline. The icon for matched groups is this. 

What is a modal? It’s simply the value that there is more of in a given field. Suppose you have marker DYS393 and 4 people have a value of “13″ and 3 people have a value of “14″. Because there are more “13″ than “14″, the modal will be 13. This is useful for seeing patterns where given kits deviate from the baseline but the modal is not significant beyond that. Why not? Because the numbers are always subject to change based on who happens to be in that grouping at any given time. Suppose, as in my example above, that 2 more people join the group today and the value of their marker DYS393 is 14. Then there would be 4 people with “13″ and 5 people with “14″, so the modal value becomes 14. As you can see on this example, when there is a marker that deviates from the modal, it’s put in white so it clearly shows.
The other grouping report is like the comparison report for markers except instead of using a haplogroup to compare kits by, the group is used. So your kit is used as the baseline for comparing everyone else in your group.  The icon for it looks like this.  Here is an example of the comparison Group report- note that the reference kit has a value of 14 at 385b, the other kits have 13 so they show in white.