The question · The precision needed · Element

The requirement

What accuracy the decision actually needs.

The part

What it is

Direction, order of magnitude, or a specific figure. The first two are usually sufficient and considerably cheaper.

Stated before the method is chosen, since the requirement should select the method rather than the reverse.

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.