Shared matches feature on Ancestry

[GingerVicky]

Hi there
I have just discovered the shared matches feature on Ancestry when you click on a match. Am I right in thinking that the list of names that appear are people that both of us share DNA with?
If that's the case why have I got matches who don't match with anyone else despite them being on the same branch?
I'm confused.
Vicky

[Gadget]

Those on a list of shared matches only show if they share at least 20cMs with your match.

[GingerVicky]

Oh right that makes sense. Thank you so much for explaining it.

[Gadget]

It's a nuisance because quite a few shareds are missed.

I'm not sure why they use 20 as the cut off.

[clayton bradley]

My husband has a cousin on his mother's side and I find that useful as we can check matches even if they are under 20cM. I also have groups of people who are not a shared match according to the person with the highest number of cMs but several other people are shared matches to them if I check those people individually. cb

[durhamgirl73]

when you click on shared matches and get more than one person bear in mind that they may not be all connected eg

John Smith and you have 5 people as shared matches

person A
person B
person C
person D
person E

you and John Smith have a match with A .... but A and B might not be connected
you and John Smith have a match with B......A C D E are all connected to each other also but B is not

hope that makes sense

[Gadget]

You have to do multiple shared match runs to find out groups of relatives - a bit like Venn diagrams 

[GingerVicky]

Yes that does make sense. Didn't think of it like that.
But if say 4 out of 5 matches are for example on the Smith side of your family and you have identified that already wouldn't it follow that the 5th person would also be on the Smith side?
This whole thing makes my brain boggle. I've still got a lot to figure out about DNA.

[Gadget]

If you click on the 5th one and do a shared match with that one, does No 5 match with the others?