Prescriptive

A methodology, endeavour, or theory is prescriptive when its primary function is to recommend action (eg, engineering, decision analysis). A prescriptive methodology serves to issue statements with the term should or ought (eg, a bridge should be built to withstand strong winds); an uncertain variable should be well defined prior to assessing a corresponding probability distribution) and must include at least one action axiom.

See also: clarity test, descriptive and normative.