1) A research design primarily used in applied behaviour analysis. The rate of target behaviour is progressively changed to some new criterion (up or down). For example, the criterion for the number of cigarettes a person smokes each day could be progressively lowered over several months. The effects of the indepent variable are shown if the subject meets or falls below the criterion for any set of days (e.g., the criterion is 20 cigarettes for week 3, but changes to 10 by week 6).

2) An applied behaviour analysis design that involves successively changing the criterion for delivering consequences, usually in graduated steps from baseline levels to a desired terminal goal. Experimental control is demonstrated if the behaviour changes to meet or approximate each successively set criterion level.

3) An experimental design in which the replications involve interventions with criteria of differing values.