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Two groups of second‐grade children were taught to read orally 30 words and were later tested for retention. One group of subjects received verbal consequences, while the other group received verbal consequences plus token reinforcement. The token group reached criterion in significantly fewer trials and correctly read significantly more words on the retention tests after the longer retention intervals.

A behavior modification program that employed feedback with no additional contingencies was initiated and withdrawn in an ABAB design on a target child within a classroom. The disruptive behavior of the target child as well as that of her peers was monitored. Additionally, the sociometric status of the target child was recorded. Finally, the positive and negative comments made to the target by her teacher and her peers were related to initiation and withdrawal of the feedback contingency. Results indicate that (1) feedback alone may be an effective behavior modification procedure, (2) the disruptive behavior of the target's classmates changed, even though they were not directly treated, (3) sociometric status of the target was altered by behavioral contingencies, (4) positive comments by classmates to the target increased, and (5) negative comments from the teacher to the target child decreased.

Nine children, ages 4 through 7 yr, matched‐to‐sample on fixed‐ratio, fixed‐interval, variable‐ratio, and variable‐interval schedules of reinforcement. Simultaneous, zero‐delay, and 2‐sec delay matching were employed. Distributions of errors, in which the greatest number of errors occurred at the ordinal position immediately after reinforcement with fewer errors occurring at subsequent positions in the ratio, were produced by six of six children on fixed‐ratio schedules for zero‐delay and both of two children for 2‐sec delay matching. Only two children of seven produced similar error distributions on simultaneous matching for fixed‐ratio reinforcement. Variable‐ratio schedules produced slightly lower accuracy for most subjects and no systematic error patterns for any subject. Error distributions occurred for all of the five children who experienced fixed‐interval schedules for zero‐delay matching. Peak error production occurred in the second fourth of the interval. Similar patterns were not produced on variable‐interval schedules of equal reinforcement density. Schedule control of complex discriminated operants in children resembles control over similar responses of nonhuman animals.

For three pigeons, reinforcement depended upon a left side‐key response after execution of a fixed ratio 10 on the center key, and upon a right side‐key response after fixed ratio 20. Each response during the fixed ratios produced a 0.5‐sec blackout. The time between the first and last response in fixed ratio 10 was then equated with the time between the first and last response in fixed ratio 20 by increasing the blackout duration. The accuracy of side‐key choice was disrupted, thereby suggesting that time, rather than number of responses, controlled choice responding. When the time between the first and last response was equated during both ratios, asymptotic accuracy was approximately equal to (two birds) or somewhat higher than (one bird) that obtained previously. The results of probes with intermediate fixed ratios and blackouts suggested that control of side‐key choice had transferred from the time between the first and last response in ratios to blackout duration.

This paper critically examines the application of fixed‐effect one‐way analysis‐of‐variance procedures to learning data from a single subject. Procedures more appropriate for data obtained from intrasubject replication designs are briefly described.

The matching law implies that any form of behavior approaches an asymptotic frequency as its reinforcement approaches 100 per cent of the total reinforcement being obtained at a given time. This asymptote is formally independent of the kind or quantity of drive or reinforcement associated with the response in question or with any competing response.

A series of experiments was conducted to establish free‐operant escape‐avoidance responding in rats using noise as the stimulus. Naive rats did not acquire a bar‐press response on an escape‐avoidance of noise schedule. Similarly, free‐operant responding established using escape‐avoidance of shock was not maintained when noise was substituted for shock. Noise stimuli of 110 dB did maintain responding, but at a lower level than during training, when the noise stimuli had first been paired with shock. Noise stimuli of 97 dB and 87 dB were not effective under those same conditions. Additional rats were trained on a free‐operant escape‐avoidance schedule of shock and then exposed to a delayed conditioning procedure in which noise was the conditioned stimulus and shock was the unconditioned stimulus. When these subjects were then tested with noise alone, two of the three subjects conditioned and tested with 105‐dB noise displayed escape‐avoidance of noise, but none of the rats conditioned and tested at 97 dB displayed escape‐avoidance of noise. The results suggest that free‐operant escape‐avoidance of noise can be demonstrated; Final Acceptance however, only higher intensity noise stimuli that have been paired with shock are effective.

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