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The matching law may be viewed either as an empirical generalization, and therby subject to disproof, or as part of a system of equations used to define the utility (“value”) of a reinforcer. In the latter case it is tautologous, and not subject to disproof within the defining context. A failure to obtain matching will most often be a signal that the independent variables have not been properly scaled. If, however, the proper transformations have been made on the independent variables, and matching is not obtained, the experimental paradigm may be outside the purview of the matching law. At that point, reinterpretations or revisions of the law are called for. The theoretical matching law is but one of many possible ways to define utility, and it may eventually be rejected in favor of a more useful definition.

Past studies have shown that disruptive behavior can be eliminated and attending behavior accelerated in an academic setting. The relationship between these behaviors and academic performance is not well understood. The effects of behavioral and performance contingencies on classroom behavior and on academic performance were investigated. The subjects, third‐grade students from an inner city elementary school, were exposed to a series of conditions including baseline, behavior contingencies, performance contingencies, and a mix of behavior and performance contingencies using a reversal design. The students worked 100 randomly selected mathematics problems for 20 minutes each day during each period. Behavioral contingencies improved attending and decreased disruptions but did not improve performance. Performance contingencies increased per cent correct problems but attending declined and disruptions increased. The combined contingencies increased both performance and attending. The experiment was replicated with another class of children varying the sequence of conditions and the amount of token reinforcement that could be earned. The findings emphasized the importance of designing specific contingencies for specific target behaviors. Behavioral contingencies did not have the positive effect on performance often implied, nor were performance contingencies alone able to maintain acceptable classroom behavior.

Measures of group participation were used in an experimental analysis of the effects of two preschool activity schedules. Children's participation in preschool activities remained as high when children were allowed no options but were required to follow a schedule of activities in sequence, as when they were free to choose between several optional activities. However, this was only true: (1) when a child was not forced to wait until all other children had finished, but could start the next required activity individually as soon as he had finished the preceding one, and (2) when there was an abundance of materials in each required activity. When there were not adequate materials in each activity, children's participation was disrupted unless they were free to choose among several optional activities. Thus, in order to maintain high levels of participation in preschool play activities, it is not necessary to allow children to choose among several alternative activities. High participation may be more efficiently maintained by providing a supply of materials that is adequate to occupy all children in each of a sequence of required activities and staffing by at least two teachers, so that while one teacher is supervising children still finishing one activity another teacher can supervise children who are ready to start the next

In a large day‐care center, measures of group participation were used to compare how much of a child's time is lost from planned activities during the daily transition from lunch, through the bathroom and dressing areas, to the nap area. Participation measures were taken using the “Zone” and “Man‐to‐Man” staffing procedures, two typical methods for dividing responsibility among teaching staff. In the “Zone” procedure, each teacher was assigned responsibility for a particular area, and for all children who passed through that area. In the “Man‐to‐Man” procedure, each teacher was assigned responsibility for shepherding a group of designated children through all activity areas during each transition. The Lunch‐to‐Nap transition using the Zone staffing assignment was accomplished with a smaller decrease in child participation in planned activities than the transition utilizing the Man‐to‐Man procedure. Thus, other things being equal, it is recommended that the Zone procedure be used in group‐care programs with more than one staff member, with each teacher being responsible for specific activity areas, rather than specific children.

Pigeons' responses in the presence of two concurrently available (initial‐link) stimuli produced entry into one of two different and mutually exclusive terminal link stimuli according to identical but independent variable‐interval schedules. In one experiment, a two‐component chained fixed‐interval schedule produced food in one terminal link while a simple fixed‐interval schedule produced food in the other terminal link. When the interreinforcement intervals were equal in the two terminal links (i.e., the simple fixed‐interval was twice the size of each of the components in the chained schedule) pigeons preferred the simple fixed‐interval as measured by their relative rates of responding in the concurrently available initial links. This preference increased as the duration of the terminal links increased. The preference could be reversed by making the simple fixed‐interval schedule sufficiently longer than the chained schedule. In the second experiment, the terminal links consisted of two‐ vs three‐component chained fixed‐intervals, again with equal interreinforcement intervals. Pigeons preferred the two‐component chain to the three‐component chain, although these results were less consistent and less dramatic than those in the first experiment. Again, preference increased as the duration of the terminal links increased. The results show that an organism's choice for a schedule will be substantially lowered by the chaining operation even when the interreinforcement interval remains constant.

The acquisition of discriminative behavior was studied in three autistic children with high‐frequency self‐stimulatory behavior. It was found that: (a) the children did not acquire the discrimination while engaged in self‐stimulation; (b) suppression of self‐stimulation produced an increase in correct responding, with eventual acquisition of the discrimination; (c) successful discrimination learning was always associated with a reduction in self‐stimulatory behavior, even when aversive stimuli were not used for suppression.

In the first study, subjects escaped shock by pressing on a lever under an unsignalled condition. By pressing a different lever they changed the condition to signalled escape for three minute periods. The second study used the changeover procedure to study inescapable‐unavoidable shock. Seven rats were used in each study. All subjects in both studies changed over from unsignalled to signalled conditions. Once contact with the signal condition was made, subjects responded to remain in that condition. The three different extinction conditions showed that the correlated stimulus without the signal had greater control over responding than the signal without the correlated stimulus. An analysis based upon shock and shock‐free periods was presented.

The effect of amount of student‐proctor interaction was investigated within the framework of Keller's (1968) method of personalized instruction. College students enrolled in introductory psychology were randomly assigned to five groups: 0%, 25%, 50%, 75%, and 100%, reflecting the percentage of units on which each student was proctored. The results indicated that (a) the proctored students were superior to the non‐proctored students as measured by final examination performance, (b) for the proctored groups, the amount of proctoring did not differentially affect final examination performance, and (c) the major effect of increased proctoring was an acceleration of the rate of progress through the course.

When a response key is briefly illuminated before a grain reinforcer is presented, key pecking is reliably developed and maintained in pigeons, even if pecking prevents reinforcement (negative automaintenance). This experiment demonstrated that pigeons are sensitive to a negative response‐reinforcer contingency, even though it does not eliminate responding. Within individual pigeons, two kinds of trials were compared: red key trials, in which reinforcement was negatively contingent on responding, and white key trials, in which reinforcement was unrelated to responding. Reinforcement frequency in non‐contingent trials was yoked to the obtained reinforcement frequency in negatively contingent trials. All eight pigeons pecked substantially more on the non‐contingent key than on the negative key, and preferred the non‐contingent key to the negative key on occasional “choice” trials where both were presented together. When the stimuli correlated with the two conditions were reversed, the pigeons' behavior also shifted. These response differences are taken as evidence that pigeons are sensitive to the negative response‐reinforcer contingency.

Token economies have been applied in a wide range of settings. While there are several advantages to the use of this procedure, there are obstacles that may impede its implementation and therapeutic efficacy. These include: staff training, client resistance, circumvention of the contingencies, and non‐responsiveness of subjects. Studies employing token programs with psychiatric patients, retardates, children in classroom settings, delinquents, and autistic children are reviewed. Although token economies are successful while in operation, the issue of generalization of behavior gains or resistance to extinction has not been given careful consideration. Inasmuch as generalization is perhaps the most crucial issue, several procedures are presented that are designed to facilitate maintenance of performance when reinforcement is withdrawn. Methodological suggestions for investigations on token reinforcement in applied settings are presented.