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Contingent reinforcement and imitative prompts were used to teach an autistic child to use simple and compound sentences to describe a set of standard pictures. When imitative prompts and reinforcement were discontinued, correct use of simple sentences declined, but increased again when imitative prompts and reinforcement were re‐instated. When imitative prompts and reinforcements were used to teach compound sentence structure, correct use of simple sentences declined and correct use of compound structure increased. At the end of training, the child also used novel compound sentences to describe a set of pictures on which he had received no direct training.

Two aides operating a kindergarten‐style program for institutionalized mental retardates were trained, using observer feedback, to apply generalized “correct” social contingencies to 10 defined classes of appropriate and inappropriate child behaviors. A multiple baseline design was used to demonstrate, sequentially, the effects of the training procedure upon the attending behavior of each teacher. After withdrawal of feedback, a posttraining follow‐up served to assess the durability of training. For both aides, the effect of training was to increase the proportion of appropriate child behaviors attended to, compared with baseline data, and a follow‐up over a number of weeks indicated that the effects of training were apparently durable.

Two experiments investigated the effect of food‐tray illumination on pecking a lighted key that signalled food presentation. Pigeons key pecked less when both feeder and key stimuli preceded grain delivery than when the keylight alone signalled food. This detractive influence of grain‐tray illumination did not result after prior pairings of the keylight with food. The involvement of associative and physical variables in autoshaping the pigeon's key peck is considered in light of these findings.

Previous studies have identified and manipulated collateral behavior to assess the effect of collateral behavior on performance under the differential‐reinforcement‐of‐low‐rate (DRL) schedule. However, conclusions could not be applied to subjects not observed to engage in collateral behavior. The present study used a technique that prevented the occurrence of the types of collateral behavior typically observed in the pigeon. This technique did not require the identification of collateral behavior in the subjects. The exclusion of the types of collateral behavior typically observed in pigeons resulted in higher response rates and lower reinforcement rates under large DRL values but had no effect at lower DRL values. It was concluded that collateral behavior is necessary for low response rates and high reinforcement rates under large DRL values.

Potential users of Keller's personalized college classroom method might find it impractical to provide student proctors from the ranks of those who had previously mastered the course material. An alternative is to let currently enrolled students proctor and tutor each other. Such a method imposes the burden of showing that its effectiveness is not a function of (1) student collaboration or (2) the effects of “practice” received by students who listen to the performance of others before their own performance. The present study compared students proctored by previously trained students (Control) with students who received proctoring from classmates (Experimental). Experimental group performance was superior to Control group performance. The effects of “practice” and collaboration were ruled out as determinants of the difference between groups. It is hypothesized that the superior performance of the Experimental students was related to their activities as proctors.

Tokens, exchangeable for a variety of back‐up reinforcers, were delivered for several days to all persons boarding a clearly marked campus bus. This procedure increased ridership to 150% of baseline. The experiment was carried out to demonstrate the applicability of operant techniques to urban transportation problems. In this study, a token reinforcement procedure was introduced in an attempt to increase bus ridership while holding the costs of reinforcers to a minimum and circumventing the problems of individual satiety and preferences and of delivering cumbersome reinforcers. A methodology for establishing a token‐exchange procedure in an “open‐field” behavior setting, where the subject population size, geographic location, preferences, age, sex, preferred hours of mobility, etc. are unspecified, is also presented.

The effects of several variables on compositional response rate were investigated in three classrooms. After establishing baseline composition rates in each of the three classrooms, an experimental phase was introduced that consisted of: explicit timing of the children's composition period with a stopwatch, immediate feedback on the number of words each child produced, public posting of the greatest number of words written by each child to date, and instructions to try to exceed their highest score. In the second‐grade classroom, these conditions were introduced, removed, and re‐introduced. In two fifth‐grade classrooms, these conditions were introduced according to a multiple baseline, across classes. In all cases, introduction of the experimental conditions led to a doubling of rate of words written by students and an increase in subjective quality ratings of compositions made by independent judges.

This study analyzed the function of two components of a personalized instruction course—mastery criteria for passing a test and assignment length. A high mastery criterion (100% correct) and short assignments produced better test performance than either a low mastery criterion (60% correct) or long assignments (four short assignments combined) on both study question items that students had in their possession and probe items that were not available to students in advance.

A change in the size of a fixed‐ratio schedule involves a simultaneous change in number of responses, in time to complete the ratio (work time), and in the interval between successive reinforcements (interreinforcement interval). Previous studies have suggested the importance of work time and the interreinforcement interval in controlling the length of the post‐reinforcement pause. The present study sought to determine whether number of responses is also a significant factor. Pigeons were trained on a multiple fixed‐ratio x fixed‐ratio 2 plus timeout schedule in which the size of the fixed‐ratio x was manipulated. When the work times (Experiment I) or interreinforcement intervals (Experiment II) were equated for the two components, the pause before the fixed‐ratio x was longer than the pause before the fixed‐ratio 2 plus timeout. As fixed‐ratio x size increased, the relative difference in the lengths of the two types of pauses also increased. Because the fixed‐ratio x component contained a larger number of responses than the fixed‐ratio 2 plus timeout component, the relatively longer pause preceding the fixed‐ratio x indicates that number of responses played a significant role in determining the length of the post‐reinforcement pause.

Three investigations were conducted on the effects of various procedures initiated by a principal on the behavior of elementary school children. Seventy nine children including kindergarten, first, third, and fifth graders served as subjects. In Experiment I, when three chronically absent children attended school, the principal entered their classrooms and praised them for being present. In Experiment II, three low‐achieving subjects were sent to the principal's office to receive praise contingent on meeting predetermined criteria in word‐recognition and addition tutoring sessions. Experiment III assessed the effects that a procedure implemented by a principal had on the academic functioning of 74 third graders. Twice weekly in two classrooms the principal recognized both improving students and the highest performing students for their work on addition study sheets. In all three experiments, the target behaviors increased when the principal applied the treatment contingencies. The application of multiple baseline designs revealed a functional relationship between the children's behavior and the procedures implemented by the principal. Since the study was carried out in an overcrowded inner‐city public school, it was suggested that the treatment procedures might be widely applicable.