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In the initial link of a complex schedule, one discriminative stimulus was presented and lever pressing produced tokens on fixed‐ratio schedules. In the terminal link, signalled by a second discriminative stimulus, deposits of the tokens produced food. With two rats, the terminal link was presented after each sixth component schedule of token reinforcement was completed. With the other two rats, the terminal link was presented following the first component schedule completed after a fixed interval. During the terminal link, each token deposit initially produced food. The schedule of food presentation was subsequently increased such that an increasing number of token deposits in the terminal link was required for each food presentation. Rates of lever pressing in the initial link were inversely related to the schedule of food presentation in the terminal link. These results are similar to those of experiments that have varied schedules of food presentation in chained schedules. Rates and patterns of responding controlled throughout the initial link were more similar to those ordinarily controlled by second‐order brief‐stimulus schedules than to those controlled by comparable extended chained schedules.

Pigeons were exposed to a series of second‐order schedules in which the completion of a fixed number of fixed‐interval components produced food. In Experiment 1, brief (2 sec) stimulus presentations occurred as each fixed‐interval component was completed. During the brief‐stimulus presentation terminating the last fixed‐interval component, a response was required on a second key, the brief‐stimulus key, to produce food. Responses on the brief‐stimulus key before the last brief‐stimulus presentation had no scheduled consequences, but served as a measure of the extent to which the final component was discriminated from preceding components. Whether there were one, two, four, or eight fixed‐interval components, responses on the brief‐stimulus key occurred during virtually every brief‐stimulus presentation. In Experiment 2, an attempt was made to punish unnecessary responses on the brief‐stimulus key, i.e., responses on the brief‐stimulus key that occurred before the last component. None of the pigeons learned to withhold these responses, even though they produced a 15‐sec timeout and loss of primary reinforcement. In Experiment 3, different key colors were associated with each component of a second‐order schedule (a chain schedule). In contrast to Experiment 1, brief‐stimulus key responses were confined to the last component. It was concluded that pigeons do not discriminate well between components of second‐order schedules unless a unique exteroceptive cue is provided for each component. The relative discriminability of the components may account for the observed differences in initial‐component response rates between comparable brief‐stimulus, tandem, and chain schedules.

This study was designed to assess the transfer of treatment gains of autistic children across settings. In the first phase, each of 10 autistic children learned a new behavior in a treatment room and transfer to a novel extra‐therapy setting was assessed. Four of the 10 children showed no transfer to the novel setting. Therefore, in the second phase, each child who failed to transfer participated in an analysis of stimulus control in order to determine the variables influencing the deficit in transfer. Each of the four children who did not transfer were selectively responding to an incidental stimulus during the original training in the treatment room. Utilizing a reversal design, each of the four children responded correctly in the extra‐therapy setting when the stimulus that was functional during training was identified and introduced into the extra‐therapy setting. The extreme selective responding and the resulting bizarre stimulus control found are discussed in relation to the issue of setting generality of treatment gains.

The influence of instructions and feedback from an experimenter on observational recordings of disruptive behavior was evaluated. Four subject‐observers recorded four categories of disruptive behavior from videotapes of children in a classroom setting. Two sets of videotapes, labelled “baseline” and “treatment”, were matched for rates of disruptive behavior in each category. The observers were told that two target behaviors were expected to decrease and the other two control behaviors were not expected to change during the treatment condition. During observational recording of treatment videotapes, the observers were given positive feedback when they reported decreases in the two target behaviors, and negative feedback when they reported either no change or increases in the two control behaviors. The target behaviors were recorded less frequently by observers, while recordings of control behaviors were unaffected during the treatment phase. These results suggest that contingent feedback to observers should be avoided as a possible source of bias in behavioral recordings.

Pigeons were exposed to multiple variable‐interval 2‐min variable‐interval 2‐min schedules of food presentation in which relative duration of food presentation was manipulated. When components alternated every 5 sec and were scheduled on separate response keys, relative response rates closely matched relative reinforcement duration in three of four pigeons. On the other hand, relative response rates were insensitive to relative reinforcement duration when components scheduled on a single response key alternated every 5 sec, and when components scheduled on separate response keys alternated every 2 min. Thus, both rapid alternation and spatial separation of components were necessary to produce approximate matching of relative responding to relative reinforcement duration. This finding contrasts with previous findings that only rapid component alternation is necessary for matching when relative rate of reinforcement is manipulated.

In most social evaluation research it is difficult to achieve the degree of experimental rigor possible in an applied behavioral study. This study illustrates how the evaluation researcher can increase experimental rigor in the analysis of social interventions. In the first evaluation, a variation of the time‐series design that offered maximum experimental control given the limitations of the situation, was employed to evaluate the effects of a specialized home‐burglary police patrol. This design revealed that no effects could be attributed to the patrol. In the second evaluation, a multiple baseline‐like design was possible in determining the effects of a police walking patrol. This design revealed that the patrol produced an increase in crime reporting but not in arrests. Social interventions often occur in a manner that allows varying degrees of experimental analysis. The evaluation researcher must attain optimal experimental analysis given the limitations of each social intervention.

The effects of several different schedules of primary reinforcement were compared in a picture‐naming task with retarded children. In Experiment I, number of correct responses and learning rate were higher under fixed‐ratio schedules than under continuous reinforcement. In Experiment II, number of correct responses and learning rate tended to be greater under intermediate than under low or high fixed‐ratio schedules. In Experiment III, number of correct responses was higher under interlocking schedules, in which the response requirement increased with time following the previous reinforcement, than under comparable fixed‐ratio schedules. Learning rates were generally low and, perhaps because of this, not very different under the two types of schedules in this experiment. Accuracy (i.e., proportion of trials on which correct responses occurred) was typically high and insensitive to variations in schedule and schedule parameter throughout each experiment.

Two groups of six rats received discrimination training with two auditory stimuli differing in intensity. During one stimulus, the schedule was variable interval; during the other, it was either variable time or extinction. Both the variable time and extinction schedules resulted in differential rates of responding in the presence of the two stimuli. Extinction resulted in an earlier and more stable difference. Stimulus generalization gradients obtained along the noise‐intensity dimension revealed peak shift with both procedures. In addition, a secondary peak to stimuli in between the two training stimuli occurred with the variable‐time schedule.

Workshops and seminars to expose different sectors of the professional community to the principles and applications of behavior modification are briefly discussed. The possible misapplication of procedures by conference participants, whose only exposure to behavioral methods has been at these workshops is viewed as a potentially serious ethical issue. It is suggested that the goals of such seminars and workshops must be clarified, and methods of evaluation of the participants' skills devised, lest we contribute to the misapplication of procedures and to the criticism that behavioral methods are unethical approaches to treatment.

Covariation within behavior repertoires of problem children were examined. Two boys, referred for psychological help, were observed both at school and at home for about 3 yr. A coded observation system permitted scoring of 19 child‐behavior categories and six social‐environment categories. After a two‐month baseline, behavior categories were intercorrelated, demonstrating that each child showed a group of behaviors that covaried. These groupings were specific to the home and school settings. Contingency management procedures were then applied to each child's problem behaviors in one setting. Next, a reversal phase was instituted, followed by resumption of the initial contingency management phase. These three phases lasted seven months, until the end of the children's public school terms. Results showed that the baseline group of covarying behaviors continued to covary over the three experimental phases. The children then entered a remedial education setting for three summer months, and then returned to schools and were observed in follow‐up for 2 yr. The baseline group of behaviors continued to covary during both phases. The behavior covariations could not be accounted for on the basis of temporal relationships between the behaviors and social environment categories. Although no behavior covariations extended across either child's home and school settings, contingency management procedures produced across‐setting effects.