Glossary
Cohort retention
Group people by when they started, then measure what share came back in each later period. It needs an identity that lasts, so usually a login.
Cohort retention groups people by when they started, then measures what share came back in each period after. Read across a row and you see one group’s curve. Read down a column and you see whether newer groups do better. A curve that flattens means some people stay.
It needs an identity that lasts for weeks, so it can’t work on a hash that rotates daily. That’s why cookieless tools usually limit it to people who sign in. In Trailic, cohorts group identified people by the Monday of the week they were first identified, and returning means any activity or an event you choose. Anonymous visitors aren’t counted at all. There’s a worked table in funnels and retention without cookies.