OVERCORRECTION: GENERALIZATION AND MAINTENANCE1

The present study examined the effects of one component of overcorrection—verbal reprimands—and compared them with the effects of the entire overcorrection procedure. Generalization and maintenance of effects were also evaluated. A combined reversal and multiple-baseline experimental design was used to evaluate the effect of the various contingencies on the inappropriate searching behavior of a severely and profoundly mentally retarded adult living in a group home. Searching was defined as carefully and thoroughly touching floors, sofas, cabinets, etc. Data were collected by group-home personnel during three separate observation periods each day of the 115-day study: before breakfast, after breakfast, and after dinner. Observers also served as experimenters. Following an initial baseline phase, verbal reprimands followed searching behavior during two daily experimental periods in multiple-baseline fashion. An immediate reduction of searching during experimental periods occurred with the onset of verbal reprimands. No reduction was observed in the third daily observation period, the control session. After a second baseline phase, during which searching behavior was not shown to return to the original baseline levels, overcorrection procedures (washing hands) were instituted. Overcorrection virtually eliminated inappropriate searching during both daily experimental periods. Further, the effects generalized to the daily control session. In a final experimental phase, decreased searching behavior was maintained with verbal reprimands alone.     

AN EXPERIMENTAL ANALYSIS OF “SPILLOVER” EFFECTS ON THE SOCIAL INTERACTION OF BEHAVIORALLY HANDICAPPED PRESCHOOL CHILDRENsp1

The effects of prompting and social reinforcement directed to target subjects on their social behavior and that of peers who never received prompting and reinforcement for positive social behavior, were examined. In a combined reversal and multiple-baseline design, three behaviorally handicapped preschool boys who exhibited divergent social behavior repertoires and varied histories with social reinforcement events, were sequentially exposed to intervention conditions in order to investigate “spillover” of treatment effects. Prompting and reinforcement increased positive social behavior and decreased negative social behavior emitted by all target subjects. The results also demonstrated a “spillover” effect on two target subjects, who at various times were not under intervention, and on the peers as well. The findings suggest that: (a) the direct and indirect effects of intervention procedures may be enhanced by designing treatment based on the social repertoire and reinforcement histories of the subjects; and (b) the treatment “spillover” effect may be increased by applying procedures to two children at once, rather than to one at a time.     

SOCIAL-SKILLS TRAINING TO MODIFY ABUSIVE VERBAL OUTBURSTS IN ADULTS

Social-skills training was used to modify abusive verbal outbursts displayed by two adult psychiatric patients. Five target behaviors—looking, irrelevant comments, hostile comments, inappropriate requests, and appropriate requests were monitored during role-played situations. Social-skills training, consisting of behavior rehearsal with modelling, focused instructions, and feedback, was introduced in a multiple-baseline design across individuals. Training improved all target behaviors. The improved behavior generalized to: (1) novel scenes role-played with the original respondent, (2) training and novel scenes role-played with a different respondent, and (3) interpersonal situations on the hospital ward.     

Time-based and count-based measurement of preference

Rats' pressing on two levers was reinforced according to two independent variable-interval schedules that were varied during the experiment. Since the levers were connected directly to the programming equipment, bypassing the standard pulseformers, reinforcement could occur while a lever was held down. Although the time a lever was pressed might, therefore, have varied independently of number of presses, these two measures covaried substantially, because the average duration of the presses remained roughly constant. This rough invariance may have resulted from the rats' tendency to make bursts of brief presses (i.e., to jiggle the levers), even though the contingencies encouraged holding. When duration did vary, presses on the two levers tended to vary together. As a result, relative time spent pressing corresponded closely to relative number of presses. Both of these measures conformed well to the matching law. Absolute behavioral frequency at a lever, measured either way, varied directly with proportion of reinforcement for that lever, in accordance with the generalized version of the matching law. Number of presses seemed, on balance, to be a slightly more reliable measure than pressing time. The substantial interchangeability may prove more significant than the slight disparity, however, because it supports the notion that all behavior can be measured on a common scale of time.     

Understanding correlates of change by modeling individual differences in growth

The study of correlates of change is the investigation of systematic individual differences in growth. Our representation of systematic individual differences in growth is built up in two parts: (a) a model for individual growth and, (b) a model for the dependence of parameters in the individual growth models on individual characteristics. First, explicit representations of correlates of change are constructed for various models of individual growth. Second, for the special case of initial status as a correlate of change, properties of collections of growth curves provide new results on the relation between change and initial status. Third, the shortcomings of previous approaches to the assessment of correlates of change are demonstrated. In particular, correlations of residual change measures with exogenous individual characteristics are shown to be poor indicators of systematic individual differences in growth.The research reported here was supported by a grant from The Spencer Foundation to the senior author and by the Study of Stanford and the Schools.     

Using aptitude measurements for the optimal assignment of subjects to treatments with and without mastery scores

For assigning subjects to treatments the point of intersection of within-group regression lines is ordinarily used as the critical point. This decision rule is critized and, for several utility functions and any number of treatments, replaced by optimal monotone, nonrandomized (Bayes) rules. Both treatments with and without mastery scores are considered. Moreover, the effect of unreliable criterion scores on the optimal decision rule is examined, and it is illustrated how qualitative information can be combined with aptitude measurements to improve treatment assignment decisions. Although the models in this paper are presented with special reference to the aptitude-treatment interaction problem in education, it is indicated that they apply to a variety of situations in which subjects are assigned to treatments on the basis of some predictor score, as long as there are no allocation quota considerations.     

The Dysfunctional Attitude Scale: How well can it measure depressive thinking?

The Dysfunctional Attitude Scale (DAS) was designed to measure patterns of maladaptive thinking held by depressed individuals. Despite its wide use as a research and clinical tool, only a few studies to date were designed to examine its psychometric properties in a clinically depressed population. Moreover, problems of low sample size and limited tests of validity call these findings into question. The present study was designed to examine psychometric properties of the DAS in clinically depressed inpatients and in nondepressed clinical controls. Intertest correlations between the DAS parallel forms and between each form with total test scores ranged from r=.84 to r=.97. Intratest stability coefficients were r=.88 to r=.97. Support for the DAS as a valid measure of dysfunctional cognitions in depressed patients was also indicated. Of those scoring high on the DAS, 73% received an independent RDC diagnosis of clinical depression, while only 36% of those receiving low DAS scores were so diagnosed.     

Judging the strength of designated evidence

Judgments of evidence strength were obtained in a series of vignettes, each containing one or two items of evidence for each of two logically independent hypotheses. Each judgment concerned a designated subset of the presented evidence. Different groups of subjects encountered different but overlapping sets of evidence. We compared groups that judged the same designated evidence for the same hypothesis, but differed in exposure to surrounding (nondesignated) evidence. Results showed clear separation of relevant from irrelevant evidence and of designated from surrounding relevant evidence. This was particularly clear in the second experiment, where judgments of designated evidence remained invariant whether the surrounding evidence supported or contradicted the specified hypothesis. The conjunction fallacy was observed for judgments of evidence strength, but was substantially reduced by a simple instruction. Because subjects can separate evidence, it becomes possible to construct cardinally scaled standards of evidence strength using conjoint-measurement methods.     

ONGOING CONSULTATION AS A METHOD OF IMPROVING PERFORMANCE OF STAFF MEMBERS IN A GROUP HOME

A model of ongoing consultation was implemented in a community group home for 8 adults with severe and profound mental retardation. Two consultants, highly experienced in working with people with mental retardation and in the procedures used in group homes, taught staff members to use a token reinforcement system, to engage the adults in a variety of activities, and to improve the content and style of the staff members' interactions with the adults. The consultants taught skills to 9 staff members through brief mini-workshops, direct observation of the staff members' use of the skills during regular activities in the group home, and individual verbal feedback regarding a staff member's performance of the skills. Evaluation of the ongoing consultation process by the 2 consultants showed it to be effective in improving the performance of the staff members and in changing the behaviors of the adults who lived in the home. Continued implementation of the process, however, appeared to be necessary for the behavior changes of staff members to be maintained at high levels.     

On the misuse of manifest variables in the detection of measurement bias

Measurement invariance (lack of bias) of a manifest variableY with respect to a latent variableW is defined as invariance of the conditional distribution ofY givenW over selected subpopulations. Invariance is commonly assessed by studying subpopulation differences in the conditional distribution ofY given a manifest variableZ, chosen to substitute forW. A unified treatment of conditions that may allow the detection of measurement bias using statistical procedures involving only observed or manifest variables is presented. Theorems are provided that give conditions for measurement invariance, and for invariance of the conditional distribution ofY givenZ. Additional theorems and examples explore the Bayes sufficiency ofZ, stochastic ordering inW, local independence ofY andZ, exponential families, and the reliability ofZ. It is shown that when Bayes sufficiency ofZ fails, the two forms of invariance will often not be equivalent in practice. Bayes sufficiency holds under Rasch model assumptions, and in long tests under certain conditions. It is concluded that bias detection procedures that rely strictly on observed variables are not in general diagnostic of measurement bias, or the lack of bias.Preparation of this article was supported in part by PSC-CUNY grant #661282 to Roger E. Millsap.