Customer Journey · Attribution · Component
The holdout
What has actually been tested by withholding, and what it showed — the only method that answers contribution rather than correlation.
The deliverable
What it is
A holdout is the only design that answers whether a channel contributes. Everything else measures whether it was present when a purchase happened.
It costs some demand for a period, which is why it is rarely run and why the organisations that run it make better budget decisions than those that do not.
One level in
What it is made of
Each element is a constituent part of the component. Follow one to see the attributes it carries.
The design
What is withheld, from whom, for how long.
3 attributes: Withheld · For how long · Control
LearnThe result
The measured difference, against the noise it has to exceed.
3 attributes: Difference · Normal variation · Conclusive
LearnThe action
What the result changed, agreed before the test ran.
3 attributes: Agreed response · Acted on · Budget moved
Learn
A holdout test whose result changed nothing was a test nobody intended to act on.
The other components in attribution
The model
Which attribution approach is used, and what it systematically over- and under-credits — because every model is wrong in a known direction.
LearnThe unobservable
What influences purchase and cannot be tracked, named so that its effect is not assigned to something else.
Learn