Whether it works · The customer measure · Element

The longer term

Whether the effect holds.

The part

What it is

Retention and repeat behaviour over months rather than conversion in a session. Short-term gains that reduce retention are a common pattern.

The control makes this measurable and is the only thing that does.

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.