When using a segment with "% split", would changing the value affect existing users?
The segment % split value will not change for an individual identity, so for example if someone is in a 10% split they will also be in an 11%, 20% or 80% split. Every Identity/Segment combination is combined and then hashed, and a floating point value between 0.0 and 1.0 is generated from this hash. This value is then evaluated against the "% Split" rule. So that number wont change for an Identity/Segment combination.
Each Identity gets assigned a float between 0.0 and 1.0. So if the Identity for that segment came out at 0.04 then they would be outside of a 5% segment but inside a 2% segment.
As an example. If you had 1000 Identities, and set the % split to 20%. You would get roughly 200 Identities in that segment. If you moved the split to 50%, you would get roughly 500. If you moved it back to 20%, you would get the exact same 200 as you originally had.
Each Identity gets assigned a float between 0.0 and 1.0. So if the Identity for that segment came out at 0.04 then they would be outside of a 5% segment but inside a 2% segment.
As an example. If you had 1000 Identities, and set the % split to 20%. You would get roughly 200 Identities in that segment. If you moved the split to 50%, you would get roughly 500. If you moved it back to 20%, you would get the exact same 200 as you originally had.
Updated on: 22/02/2021
Thank you!