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Food‐reinforced key pecking in the pigeon was maintained under a four‐component multiple schedule. In two components, responding was maintained at high rates under a random‐ratio schedule. In the other two components, responding was maintained at low rates under a schedule that specified a minimum interresponse time. For both high and low response rates, one of the schedule components was associated with a high reinforcement frequency and the other components with a lower reinforcement frequency. During performance under these schedules, a stimulus terminated by access to response‐independent food was periodically presented. The duration of this pre‐food stimulus was 5, 30, 60, or 120 sec. Changes in rate of key pecking during the pre‐food stimulus were systematically related to baseline response rate and the duration of the stimulus. Both high and low response rates were increased during the 5‐sec stimulus. At longer stimulus durations, low response rates were unaffected and high response rates were decreased during the stimulus. For two of three pigeons, high response rates maintained under a lower frequency of reinforcement tended to be decreased more than high response rates maintained under a higher reinforcement frequency. In general, the magnitude of decrease in high response rates was inversely related to the duration of the pre‐food stimulus.

In Experiment I, lever pressing by rats was maintained by the delivery of food pellets under a 45‐sec fixed‐interval schedule. Fixed‐time 180‐sec and fixed‐interval 180‐sec schedules of shock delivery were systematically superimposed on the baseline food schedule to study effects on schedule‐induced water intake. Response‐dependent shock had little, if any, effect on water intake, whereas shocks independent of lever pressing attenuated fluid intake. In Experiment 2, rats received food pellets under a fixed‐time 60‐sec schedule. Electric shock delivered concurrently under a variable‐time 180‐sec schedule, but never while the animal was licking or within 5 sec after licking terminated, led to similar attenuation of water intake. These findings suggest that schedule‐induced polydipsia is sensitive to differences in the functional properties of response‐independent and dependent electric shock.

In zero‐delay matching procedures the performance of three groups of pigeons was examined when exteroceptive stimuli, response‐produced stimuli associated with the completion of either of two fixed ratios, or a compound of exteroceptive and response‐produced stimuli were available as samples. Exteroceptive samples were found to control a higher level of matching accuracy than response‐produced samples, while compound samples controlled a higher level of accuracy than did exteroceptive samples alone. When all subjects were placed on a transfer procedure, during which the previously used red and green samples were replaced by horizontal and vertical lines, the availability of sample‐specific fixed‐ratios facilitated acquisition of the task.

Swimmers' attendance at training and work rates were described by their coaches as being poor and irregular. Reinforcement contingencies were developed to remedy these unsatisfactory conditions. Two experiments were conducted. A multiple baseline design verified the effects of publicly marking attendance at practice as a sufficient solution for reducing absenteeism, tardiness, and leaving early. Follow‐up analyses showed this contingency to have lasting effects. In the second experiment, a reversal design was used to assess the effects of employing program boards as a means of increasing work output during practice. Work rates in eight selected swimmers were elevated by an average of 27.1% when the boards were instituted. Follow‐up evaluations showed that the use of the program boards had lasting effects. Publicly checking the completion of each training unit of work changed the nature of the swimming environment to produce a more productive use of time. The role of the coach was subsequently changed as less time was spent in directing and supervising behaviors.

An audit response allows access to an existing score from a subject's own performance (self audit) or from his coactor's performance (coactor audit). A previous study found that social stimuli (coactor present) increased audits relative to a non‐social (no coactor) condition. The increase, designated a social‐stimulus effect, was found to be due more to the coactor's score than to his mere presence. This finding suggested that the difference between self and coactor scores might affect the size of the social‐stimulus effect. In the present study, six pairs of human subjects matched‐to‐sample for points that were exchangeable for money. During a session, matching‐to‐sample problems were distributed so that a subject's score was ahead, behind, or about even with his coactor's score. The even condition produced the largest social‐stimulus effects, i.e., the most audits that could not be attributed to nonsocial variables such as time or number of problems. The even condition may have produced the largest social‐stimulus effects because it was the only condition where the major social reinforcer (being ahead) could be both present or absent and, consequently, the even condition was the only one where audits had a discriminative function with respect to the presence of the major social reinforcer.

Three pigeons were exposed to a positive automaintenance procedure in which each trial began with a brief tone followed by the transillumination of a small central area of the response key for 10 sec. Key illumination was followed by food on 100%, 50%, 25%, 12.5%, and 0% of the trials. The effects depended on the dependent variable observed. The mean rate of responding during key illumination rapidly increased and then decreased slightly as the percentage of key illuminations paired with food increased. The number of key illuminations during which at least one response occurred increased as a negatively accelerating function of the percentage of key illuminations paired with food, and the mean latency to the first response during the key illuminations decreased as a negatively decelerating function of the percentage condition. The mean rate of sustained responding during key illumination was not systematically affected by changes in the percentage conditions.

Behavior modification procedures have typically been used to eliminate discipline problems in the classroom through reinforcement of nondisruptive behavior. This report demonstrates an alternative approach whereby discipline problems are eliminated by reinforcing relevant academic skills. Five fifth‐grade boys, identified by their teacher as discipline problems, were observed. The teacher conducted 15‐min performance sessions in her reading class during which written academic performance and disruptive behavior were recorded. These measures indicated that the boys' average level of disruption was 34%, while their reading performance was below 50%. When systematic token reinforcement was applied to reading performance only, the rate of disruption fell drastically, and reading performance increased. When the reinforcement procedure was withdrawn, disruption again rose, and reading performance declined. The reinstatement of reinforcement doubled reading performance and eliminated disruption.

Reading stories at bedtime was made contingent upon nonthumbsucking for girls 3, 6, and 8 yr old. According to their mothers, all had been persistent thumbsuckers since infancy. Two had accompanying dental disorders. During baseline conditions, continuous noncontingent reading occurred. During experimental conditions, reading terminated on each occasion thumbsucking was observed and resumed immediately when thumbsucking ceased. High percentages of thumbsucking occurred during baseline conditions when reading was noncontingent, and low percentages occurred during experimental conditions when reading was contingent. Bedtime thumbsucking was eliminated for all three girls.

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