Attribution · The holdout · Element
The action
What the result changed, agreed before the test ran.
The part
What it is
Deciding beforehand is what prevents an inconvenient result being explained away, which is the normal fate of holdout findings.
A test whose result changed nothing was a test nobody intended to act on.
The smallest level
The attributes it carries
Each attribute is one of the framework’s shared types. What a date is, and how it is written, is defined once for the whole model — the note here says what it means in this particular place.