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The effect of nonverbal teacher approval (physical contact in the form of patting approvingly) delivered to target subjects on the attentive behavior of adjacent peers was examined in a special‐education classroom. In a reversal design, two pairs of moderately retarded children were exposed to nonverbal approval, with only one subject in each pair receiving approval. In different phases, nonverbal approval was delivered alone or in conjunction with a verbal prompt directed to the adjacent peer or to the class as a whole. The prompt was designed to make salient the target subject's attentive behavior and the nonverbal reinforcing consequences that followed. Providing contingent nonverbal approval alone consistently altered attentive behavior of the target subjects but did not alter the attentive behavior of adjacent peers. However, accompanying nonverbal approval with a verbal prompt did increase attentive behavior of nonreinforced peers.

Three human subjects detected unpredictable signals by pressing either of two telegraph keys. The relative frequencies with which detections occurred for the two alternatives were varied. The procedure included a changeover delay and response cost for letting go of a key. All subjects matched the relative time spent holding each key to the relative number of detections for that key, in conformity with the matching law. One subject's performance, which at first deviated from the relation, came into conformity with it when response cost was increased. Another subject's performance approximated matching more closely when the changeover delay was increased. The results confirm and extend the notions that choice consists in time allocation and that all behavior can be measured on the common scale of time.

Pigeons were trained on concurrent schedules in which key pecking was required by both schedules (concurrent variable‐interval variable‐interval schedules) and on concurrent schedules in which key pecking was required by only one of the schedules (concurrent variable‐interval variable‐time schedules). The distribution of reinforcements was systematically varied with both types of concurrent schedules. The distribution of time between the schedules depended on the reinforcement distribution and was independent of the symmetry of the response requirement. The relation between time and reinforcement distributions appears to be invariant over a wide range of manipulations of responding maintained by concurrent schedules.

The need for self‐care by retarded individuals in behaviors such as brushing teeth led to the development and evaluation of a comprehensive toothbrushing program that included a task analysis and training procedure specific to each component of the task analysis. Eight mentally retarded adolescents, in two groups, individually received acquisition training that included scheduled opportunities for independent performances, verbal instruction, modelling, demonstration, and physical assistance. The first group of four subjects received token plus social reinforcement; the second received only social reinforcement. All eight subjects showed improved toothbrushing behaviors when compared to baseline. Six of the eight subjects correctly performed all toothbrushing steps in two of three consecutive sessions. The study emphasizes the need for systematic program development and evaluation.

The effect of an instructional package on public‐speaking behaviors was analyzed in two experiments. The instructional package was designed to teach public‐speaking trainees to look at the audience, make gestures, and perform a number of speaking behaviors. The results of Experiment I, with a university student serving as the trainee, showed that the percentage of each category of public‐speaking target behavior increased only after the instructional package was introduced for that category. The results of Experiment 2, with three low‐income paraprofessional staff members of a neighborhood service center serving as trainees, showed that the percentage of target behaviors increased after the instructional package was introduced for the respective trainee. Audience ratings of public‐speaking performance were correlated with direct observations of target responses. All trainees showed marked improvements in audience ratings from pretraining to posttraining. This study demonstrated an effective procedure for training public‐speaking behaviors.

Pigeons were trained on a modified three‐key matching‐to‐sample procedure, in which only one comparison key (rather than two) was lighted after an observing response to the center‐key standard. Pecks on keys of matching comparison hues were reinforced. When nonmatching hues appeared as the initially lighted comparisons, the nonmatching hue terminated and the matching hue appeared on the other side key only if the pigeon did not peck the nonmatching comparison for 4.8 sec. Pecks to the nonmatching hue reset the 4.8‐sec delay interval. Three hues were used during acquisition. During transfer tests, two novel hues were substituted individually or together for one or two of the training hues. Latencies to the novel side‐key hue were shortest when a novel matching hue appeared as the standard on the center key, and were essentially identical to baseline matching latencies. In contrast, when a novel hue appeared as either a standard or comparison in a nonmatching combination, latencies increased with increasing separation between the novel hue and the nonmatching hue. These transfer data demonstrate the concept of hue matching.

Fifteen overweight girls aged 5 to 11 yr were randomly assigned to one of two weight‐reduction treatments: response‐cost plus reinforcement, response‐cost only, or a no‐treatment control group. In the response‐cost plus reinforcement group, parents contracted to facilitate their child's weight loss by carrying out reinforcement and stimulus control techniques, completing weekly charts and graphs, and encouraging their child to exercise. The response‐cost only group parents did not contract to reinforce their child's performance. The response‐cost program applied to both experimental groups was conducted in weekly meetings in which parents lost previously deposited sums of money. Twenty‐five per cent was deducted for missing the weekly meeting, 25% for failing to fill out charts and graphs, and 50% if their child failed to meet her specified weekly weight‐loss goal. At the end of the 12‐week treatment period, both experimental groups had lost significantly more weight than the control group. After an eight‐week, no‐contact follow‐up, some of the lost weight was regained. The response‐cost plus reinforcement group was still significantly below the controls. The response‐cost group just missed significance. A 31‐week, no‐contact follow‐up failed to show a treatment effect, but did show a trend towards slower weight gain by the response‐cost plus reinforcement group.

Two‐component schedules of differential‐reinforcement‐of‐low‐rate were presented, where the contingencies specified separately two minimum interresponse times, t1 and t2, required for reinforcement, depending on whether the interresponse time was initiated by, in one case, a reinforced response (t1) or, in the other, a nonreinforced response (t2). A distinctive pattern of responding developed on each of the two contingencies. Duration of an interresponse time approximated t1 when the t1 contingency was in effect, and t2 when the t2 contingency was in effect. This relationship persisted even when t2 was shorter than t1, and responding at a higher rate on the t1 contingency would have greatly increased the rate of reinforcement. Increasing the value of t2 resulted in both longer interresponse times on the t1 contingency, and a higher probability of a response‐burst on those occasions when the contingency switched from t1 to t2. The results indicated that both reinforced and nonreinforced responses functioned as discriminative events in determining the duration of following interresponse times.

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