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This study evaluated the effectiveness of an incentive procedure designed to increase the punctuality of six workers who were chronically late to work in a manufacturing company. The six workers in the experiment received a 2.00 pesos ($0.16 U.S.) bonus for every day that they arrived on time. A reversal design was used. The contingent bonuses increased the workers' rates of punctuality compared to their baseline rates. A control group of six workers observed during the same 77‐week period showed a trend toward decreasing punctuality. These results suggest that the use of small daily bonuses is a practical procedure for modifying chronic tardiness among industrial workers.

Children responded on a single operandum to produce marbles or candy within a two‐component multiple schedule and then were allowed to choose which component was in effect. Experiment I examined the effects of exchanging marbles after sessions for subject‐selected or experimenter‐selected candy. Rate of response to the single operandum was not affected. However, when the subjects could switch components, they spent the majority of time and responded at somewhat higher rates in a component where marbles were exchangable for subject‐selected candy. Experiment II examined the effects of eliminating the immediate marble consequence for responses. Rate of response to the single operandum was not affected. However, when subjects could switch components they spent more time in a component where immediate marble consequences were available for responses, than where no immediate marble consequences were available.

Lever pressing was maintained by Sidman's shock‐postponement procedure and Herrnstein and Hineline's shock‐frequency‐reduction procedure with rats. Food deprivation to 80% and 70% of the animals' body weights on free feeding resulted in decreased response rates in both avoidance paradigms tested. Reinstatement of free‐feeding conditions increased body weights and response rates and decreased shock rates. The effects of food deprivation were not dependent upon any particular avoidance parameters, or types, intensities, or durations of electric shock. These results mean that weight control is essential in long‐term studies of avoidance behavior, and in studies of the effects on avoidance behavior of physiological interventions, such as hypothalamic lesions, that themselves may produce weight changes.

The effects of unstructured peer‐tutoring procedures on the math performance of fourth‐ and fifth‐grade students were investigated. Students' performances in two daily math sessions, during which they worked problems of the same type and difficulty, were compared. When students tutored each other over the same math problems as they subsequently worked, higher accuracies and rates of performance were associated with the tutored math sessions. The use of consequences for accurate performance seemed to enhance the effects of tutoring on accuracy. The results from an independent‐study control condition, which was the same peer‐tutoring except that students did not interact with each other, suggested that interactions between students during the tutoring procedure were, in part, responsible for improved accuracy and rate of performance. When students tutored each other over different but related problems to those that they were subsequently asked to solve, accuracies and rates during tutored math sessions were also higher, suggesting the development of generalized skills in solving particular types of math problems.

Rats were trained to press a lever, with every response reinforced with water. After responding was established, nine rats were administered a brief shock after each lever press, and nine others were shocked after drinking. The two procedures resulted in similar suppression of responding, and examination of the latency data when responding was partially suppressed indicated that under both conditions response suppression was due primarily to an increase in the latency of the instrumental response, rather than to pausing between the instrumental and consummatory responses. Thus, punishment following either the instrumental or consummatory component of the simple response sequence reduced the number of sequences initiated, rather than selectively suppressing the punished behavior.

This experiment was designed to compare the effects of contingent reinforcement under conditions of self‐determined and externally imposed performance standards. A major purpose was to examine the maintenance of self‐imposed performance standards over time. Children in one contingent reinforcement condition self‐determined their academic performance standards. The same performance standards were externally imposed upon children in a second contingent reinforcement condition who were yoked to subjects in the first condition. Children in a no‐reinforcement control condition performed in the absence of external reward. Behavioral productivity of the self‐determination condition was greater than that of the no‐reinforcement condition. Further, no attenuation of the efficacy of contingent reinforcement occurred when performance standards were self‐determined rather than externally imposed. Over six sessions, children became progressively more lenient in their self‐imposed performance demands in the absence of social surveillance.

Discriminative responding in pigeons was studied under multiple variable‐interval extinction schedules in which extinction was correlated with either a tone or a white keylight. The two procedures resulted in weak and strong stimulus control, respectively. In the first experiment, there was no interaction between schedule components when stimulus control was strong and reinforcement was omitted under the previously reinforced component, However, there was marked induction between components when stimulus control was weak and responding was extinguished under the previously reinforced component. In the second experiment, hours of food deprivation was varied under two levels of stimulus control. Deprivation mainly influenced response rates under the extinction stimulus, with greater absolute rate increases occurring the lower the existing level of stimulus control. Increases in responding during the extinction stimulus were four times as great from 24 to 72 hours of deprivation as from 24 to 48 hours under conditions of both high and low stimulus control.

Pigeons made observing responses for stimuli signalling the availability of either 10‐sec or 2‐sec access to grain on fixed‐interval 1‐min schedules. If observing responses did not occur, food‐producing responses occurred to a stimulus common to both reinforcement magnitudes. When the stimuli remained on for the duration of the components and signalled differential reinforcement magnitudes, observing responses were maintained; however, when the stimuli remained on for 10 sec, observing responses decreased markedly. In addition, it was shown that the occasional presentation of the stimulus signalling 10‐sec access to grain was necessary for the maintenance of observing behavior. A control condition demonstrated that when all the available stimuli signalled 6‐sec access to grain, observing responses declined. Taken together, the results demonstrated that the occasional presentation of the stimulus that remained on for the duration of the component and signalled the larger reinforcement magnitude was necessary for the maintenance of observing behavior.

Two experiments were conducted with pigeons to examine the effects of procedures that varied information transmission on observing responses. The basic procedure for Experiment I was one in which a trial terminated in either non‐contingent reinforcement or timeout. Pecking during a trial produced either green (positive) or red (negative) keylights. If no pecking occurred no differential stimuli appeared. The probability of positive trials was either 0.25, 0.50, or 0.75. Observing response rates and relative frequencies of occurrence were highest when the probability of positive trials was 0.25 and lowest at 0.75. In Experiment II, a modified chain procedure was used in which responding produced either red or green lights. Reinforcement or timeout followed light onset by 15 sec. The correlation between the stimuli and the event at the end of the trial (reinforcement or timeout) was varied. Reinforcement followed green 100%, 90%, 70%, or 50% of the time that green occurred. Since the overall probability of reinforcement remained at 0.50, reinforcement followed red in either 0%, 10%, 30%, or 50% of the time that it occurred. The rate of responses that produced these stimuli varied as a function of the correlation. The greater the probability of reinforcement after green, the higher the response rate.

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