Ancestry removing matches less than 8cM

[jillruss]

I too had only just noticed that all matches below 10cMs have now gone to decimal points. This does indeed make me suspicious that these will soon be disappearing as well. What on earth is going on with Ancestry?

Before we know it, we'll be lucky to retain any matches below 20cMs which seems to be their cut-off for more distant 'cousins'.

(Ancestry hasn't had a sudden takeover by the current government, has it? I mean, the words 'brewery' and '--ss up' spring to mind!) 

[Flemming]

The cynic in me says they are intentionally reducing the number of matches we've got to validate theories and break down brick walls. The lower matches, in particular, are very useful for brick walls further back in time. If we have less to work with, we stick with Ancestry longer in the hope that some sort of match will turn up one day to help.

I’m just glad I cracked some of the blocks before now as I’d have no way of doing this after the lower matches are removed. I don’t have time to go through every <8cM match and mark them, and what a ludicrous option it is anyway - hugely inefficient for us (impossible for people with certain health issues), slows down their ‘back end’ while we’re doing it, and means those who have done it keep all the matches anyway. Why didn’t they just offer an ‘opt in - opt out’ function? I can imagine the majority wouldn’t do anything with such an option, and only a small percentage opt to keep the low matches - which they’ve offered an alternative cumbersome way of doing anyway.

Does anyone at Ancestry actually think these things through?

Sorry for the moan, but it’s just so inefficient and such poor customer service on their part.

[LizzieL]

By using the automatic tagging programme mentioned up thread I have given all my 6 and 7 matches a group assignment, but now I realise that higher matches might also be vulnerable.

One of the things that seems to be happening or may have already happened is the change in number of segments

Quote from Ancestry:

More accurate number of shared segments (beginning early August)

The DNA you share with a match is distributed across short segments, long segments, or some combination of both. Our updated matching algorithm may reduce the estimated number of segments you share with some of your DNA matches. This doesn’t change the estimated total amount of shared DNA (measured in centimorgans/cM) or the predicted relationship to your matches.

I have a match with a person on Ancestry which says it is 34 across 2 segments. She has uploaded to My Heritage and there it says our match is 47.7 across 3 segments. The size of the segments are 21.0, 21.4 and 6.3, so Ancestry has chopped out the small segment and also seems to have reduced the length of the other two to get a total size smaller than My Heritage.
I have  several matches in the low teens over 2 segments, potentially both those segments could be below 8 individually, so will I lose the whole match even though the total may be 12 or 13?

[melba_schmelba]

By using the automatic tagging programme mentioned up thread I have given all my 6 and 7 matches a group assignment, but now I realise that higher matches might also be vulnerable.

One of the things that seems to be happening or may have already happened is the change in number of segments

Quote from Ancestry:

More accurate number of shared segments (beginning early August)

The DNA you share with a match is distributed across short segments, long segments, or some combination of both. Our updated matching algorithm may reduce the estimated number of segments you share with some of your DNA matches. This doesn’t change the estimated total amount of shared DNA (measured in centimorgans/cM) or the predicted relationship to your matches.

I have a match with a person on Ancestry which says it is 34 across 2 segments. She has uploaded to My Heritage and there it says our match is 47.7 across 3 segments. The size of the segments are 21.0, 21.4 and 6.3, so Ancestry has chopped out the small segment and also seems to have reduced the length of the other two to get a total size smaller than My Heritage.
I have  several matches in the low teens over 2 segments, potentially both those segments could be below 8 individually, so will I lose the whole match even though the total may be 12 or 13?

Lizzie, I think they are only hiding those matches where the total cM is below 8, not those made up of multiple smaller segments under 8. They still have smaller sized segments around as I have matches of 7.0 cM with 2 segments!

[LizzieL]

Thank you, that's reassuring.

[lisalisa]

I notice 'longest segment' (underneath shared dna) is showing up this morning.
Not yet sure how much help it will be.


Having now looked at a few of these (where I know the relationship), I'm not sure how it will help.

Added
eg. a new match has shared 14cM acr 2 segments, longest segment 8cM.
so this is making me think that the 8cM is a more 'likely' distance for the connection to be, however that is all governed overall by the random nature of how much dna is inherited and then shared, I think.  So this could be a somewhat closer match, than suggested by the 8, if the amount of shared dna is lower to start with.  So just a guide then - perhaps easier to see once the connection is known.  (I don't know this one).

[LizzieL]

I notice 'longest segment' (underneath shared dna) is showing up this morning.
Not yet sure how much help it will be.


Having now looked at a few of these (where I know the relationship), I'm not sure how it will help.

Added
eg. a new match has shared 14cM acr 2 segments, longest segment 8cM.
so this is making me think that the 8cM is a more 'likely' distance for the connection to be, however that is all governed overall by the random nature of how much dna is inherited and then shared, I think.  So this could be a somewhat closer match, than suggested by the 8, if the amount of shared dna is lower to start with.  So just a guide then - perhaps easier to see once the connection is known.  (I don't know this one).

Just looked at mine - doesn't make any sense
I have a match supposed to be 34 over 3 segments but longest segment is 49

[Gadget]

I think they've made an error, Lizzie.

I've just been looking at some shared matches  in a friend's DNA and all of them from the first at 488cM to the last at 20cM have the longest segment as 26.

Maybe they were testing 

[Gadget]

Funny - I've just looked at mine and they run from 154 (shared 1846) to 7 for a shared cM of 6.9.  So what are they doing?

 

add - and an 8.4cM across 1, with largest seg as 10!