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Pupil Preferences and the Premack Principle

In his now classic paper of 1959, David Premack reinterpreted the positive reinforcement effect as follows: "Reinforcement results when an R of a lower independent rate coincides, within temporal limits, with the stimuli governing the occurrence of an R of a higher independent rate [p. 219]" (italics original). Among other implications of this reinterpretation is the following which has direct applicability to educational problems: of two behaviors performed by an individual, the more preferred (operationally defined as the one with the higher independent frequency of occurrence) can reinforce the less preferred, but not vice versa. Premack demonstrated this effect, now often referred to as the Premack Principle, on several species (e.g., Premack, 1959, 1962, 1965, 1971). In his study on humans (Premack, 1959) each of the 33 first graders was exposed to a candy dispenser and a pinball machine and told that he could play with either or both games as much as he liked. This first exposure to the games established' 'empirical independent rates (as measures of preference) for the two behaviors. The second trial provided a test of the principle by establishing the following contingency relationships. Half the Ss found that the availability of their preferred behavior (either manipulating the pinball machine or eating candy) was not contingent upon performance of their nonpreferred behavior (eating or manipulating, respectively). This was ac-