Ancestry Matches 7cM and less

There is an option to a 'Hide' a specific match and, I think, doing so removes you from that match's list too. Also, you can opt out of matching altogether which likewise removes you from any list in which you are shown as a match. So if one of your matches uses one of these options it will reduce the number of matches in your list.

 

It would seem so - the number of shared segments has now reduced on my matches. For instance, earlier this week I shared 52 segments with my sister and now it is only 42.

 

Ah yes, now my husband and I only share 33 and 26 segments with our son, whereas previously it was 87 and 79 respectively.

 

Well spotted.
Similarly with my close matches. I had a coloured grouping which consisted entirely of low level matches with more than one segment because I was worried about losing some. Some of the entries in this group now show just 1 segment, but the total number of cMs hasn't changed so a match that was previously 8.8 across 2 segments is now 8.8 across 1 segment. So probably needn't have worried after all.

 

Can I just say - hopefully not treading on too many toes - this is without doubt the most boring topic being aired in the Forum. I am even upset with myself for becoming its 147th contributor. But there is a solution I should have taken long ago and that is to 'Unfollow' and leave you all bemoaning worries that will all all end as a storm in a teacup. Sorry !

 

I stand corrected.

 

I've had a total of 25 new matches in the last 7 days, including some yesterday and this morning, 10 of which are under 8cM.

 

Similar - hence my apology!

 

My DNA matches are now showing the size of the longest shared segment.

 

Following on from what I wrote earlier, I was checking out a new match with whom I share 28 cM across 2 segments, and was surprised to see that the longest segment is shown as 27 cM.

Even allowing for one being rounded up and the other down, the second segment must be very short and I'm quite surprised it has been included.

 

My matches are also showing longest segment. Could anybody explain why I have a shared match that is shorter then the longest

Shared DNA: 7.5 cM across 1 segments
Longest Segment: 15 cM

 

Is this because Ancestry has adjusted the length of shared DNA to reflect that DNA can be shared for other reasons. Ancestry has reduced the reported shared match value from 15 to 7.5cM. This could explain why other sites give a higher value for a match then AncestryDNA.

 

It is likely that the two segments are both over 6cM but have been adjusted down with one of them having been previously reduced from 28cM.

 

I checked my top 48 matches and many of those with a single segment had a longest segment that was larger than the total shared segment (19 in total meet that criteria).
The largest discrepancies were
shared DNA 49cM and longest segment 60cM
shared DNA 48cM and longest segment 59cM
shared DNA 38cM and longest segment 50cM

I also have cases where longest segment would mean that other segments are 3-4cM in length

I think they must be using different criteria for shared DNA and longest DNA segment

 

Could it be that Ancestry are looking at all the shared matches and showing the longest matching segment of the overlapping matches rather than the match being looked at?

To illustrate what I mean, the image is showing the segments for two matches (from MyHeritage). One is 36cM (though Ancestry have 17cM due to different algorithms), the other 27.4cM.

 

I have a match with “xyz” of 24cM across 1 segment and a longest length of 49cM. Looking at all my shared matches with “xyz”, I have 49cM as the longest length for each of these shared matches with “xyz”, the shared match ranges from 44cM to 22 cM. This is the case with all my matches with 1 segment shared. Triangulation would also yield the same results.

 

Yes - but the shared segments have already been updated or do you mean that those with a single segment have not been updated?