EFFECTS OF REINFORCEMENT HISTORY AND INSTRUCTIONS ON THE PERSISTENCE OF STUDENT ENGAGEMENT

We examined the effects of three reinforcement histories on the persistence of task engagement by 2 fourth-grade students using a partially counterbalanced ABCDBCD design. In each condition, an experimenter made four student contacts during the first 2 min of each session (reinforcement baseline), followed by an 8-min extinction period. The reinforcement history that contained an instructional control component produced the greatest persistence in student engagement. The applied relevance of instructional control is discussed.     

“Make things as simple as possible, but no simpler.” A rejoinder to Scruggs and Mastropieri

Scruggs and Mastropieri (Behaviour Research and Therapy, 32, 879–883, 1994) take issue with criticisms of their PND (Percent of Nonoverlapping Data) statistic that we offered in our recent article (Allison & German, Behaviour Research and Therapy, 31, 621–631, 1993), which advocated a regressionbased method for obtaining effect sizes in single-subject studies. They contend that their PND approach has several advantages over our approach because: (1) they believe that, unlike ours, it can take advantage of the small number of observations that are typically available in single-case studies; (2) it is simple to compute; (3) it frees researchers from traditional regression assumptions of normality, homogeneity of variance, and independence of observations and residuals; and (4) it correlates with visual judgements made by experts. As we shall argue, these claims are built upon very questionable assumptions and they are very difficult to substantiate. In addition, we show that the expected value of the PND is so strongly related to sample size as to be rendered meaningless.     

Division of labor in conversations: Are Fishman's results replicable and generalizable?

Fishman's (1978a) conclusion that women do the bulk of the support work in their conversations with male partners has had widespread appeal. In this article, we present the results of two studies designed to assess the generalizability and replicability of her findings. In Study 1. the get-acquainted conversations of 20 mixed-sex, 10 male same-sex, and 10 female same-sex dyads were analyzed for the support strategies identified by Fishman. No support for a sexual division of labor was found. In Study 2, we analyzed the casual, at-home conversations of 17 intimate male-female couples. Again, we found no evidence that the women used more of the support strategies than their male partners. Rather, our findings suggest that the women may have helped to sustain the conversations with their male partners simply by talking more. The appeal of Fishman's conclusions in the absence of empirical evidence suggests that she has touched on a mythic truth.This article is based on a Master's thesis by the second author (Study 1) and an Honour's thesis by the third author (Study 2) under the supervision of the first author.     

Effects of surface texture on weight perception when lifting objects with a precision grip

In this paper, we show that, when lifting an object using a precision grip with the distal pads of the thumb and index finger at its sides, the perceived weight depends on the object’s surface texture. The smoother the surface texture, the greater the perceived weight. We suggest that a smoother object is judged to be heavier because the grip force, normal to the surface, required to prevent it from slipping is greater. The possibility of there being an influence of surface texture per se is excluded by a second experiment that employed a variant of the precision grip in which the thumb supports the weight of the object from underneath. With the grip oriented in this way, there is no need to match grip force to surface texture and, under these conditions, there is no effect of surface texture on weight perception. In the first two experiments, the test and comparison weights were lifted successively by the same hand. In a third experiment, the effect of surface texture was replicated for sequential lifts made with separate hands. Thus, the effect is not restricted to comparisons made with the same hand.     

Evaluations of Tests Used for Making Selection and Promotion Decisions

Participants (N= 212) rated the fairness, job relevance, appropriateness, and invasiveness of 16 tests that could be used to select or promote people into production or management positions. Fairness, job relevance and appropriateness were highly correlated, and were combined to form a composite evaluation scale. Evaluations and invasiveness ratings varied among the 16 tests, with the most positive ratings given to interviews and work samples and the most negative ratings given to astrology, graphology and polygraphs. Evaluations of four tests were affected by the position (manager vs. production worker). Evaluations of 11 tests and invasiveness ratings of two tests were affected by respondent experience with the test. Respondents who had experienced the tests evaluated them more positively and considered them to entail a smaller invasion of privacy. Responses were not affected by whether the test was to be used for selection versus promotion decisions.     

Beyond the relational principle of reinforcement

Behavior under baseline conditions in which the contingency is absent can shed some light on the individual's performance under a schedule, but is insufficient as a basis for prediction of performance. This insufficiency of the baseline data runs counter to a recent formalization of the relational principle of reinforcement (Donahoe, 1977). A more satisfactory predictive model must incorporate not only the baseline level of the instrumental response and that of the contingent response, but also the schedule requirements, the character of each response in relation to the other, and the behavior required in simply switching from each to the other.     

Behavioral coaching in the development of skills in football, gymnastics, and tennis

A review of the literature indicates that methods of skill acquisition based on the operant paradigm have been scientifically validated with many motor behaviors. However, these procedures have been limited to the use of positive reinforcement for correct performance when applied to the acquisition of complex sports skills in natural settings. To find complementary procedures to enhance skill acquisition, a coaching method involving several behavioral techniques was developed that focused on remediation of errors. This coaching method combined the following components: (1) systematic use of verbal instructions and feedback, (2) positive and negative reinforcement, (3) positive practice, and (4) time out. Three sports, football, gymnastics, and tennis, were selected to determine the effectiveness and generality of this behavioral coaching method. A total of 23 male and female subjects, ranging in age from 11 to 35, was included in this study. Baseline data were first collected for each sport under standard coaching conditions. Next, the behavioral coaching method was evaluated depending on the sport in either a multiple baseline or a reversal design. The behavioral dimensions selected were blocking in football; backward walkovers, front hand springs, and reverse kips in gymnastics; and the forehand, backhand, and serve in tennis. Behavioral coaching was immediately effective in increasing the correct execution of complex skills in all three sports. Gains of up to 10 times the baseline performance were achieved in each sport. In football, behavioral coaching resulted in an increase in correct blocking performance from a baseline average of 5% to 51.3%. Gymnasts' performances increased from baseline averages of 2.7% to 52.6% across the three skills. In tennis, standard coaching produced an average of 6% correct performance which increased dramatically under behavioral coaching to 57% across the three strokes. The success of the behavioral coaching package used here suggests that a technology of behavior may offer additional and complementary strategies to the acquisition of motor skills in the natural environment.     

Assessment of incarcerated juvenile delinquents: Agreement across raters and approaches to psychopathology

The purpose of the current study was to examine the agreement across three informants (youth, teacher, caretaker) when rating behaviors of incarcerated juvenile delinquents. Furthermore, the agreement between a dimensional approach (Child Behavior Checklist) and a categorical approach (DSM-III-R) of assessing behavior was examined. Fifty-two delinquent youth were assessed with a structured interview. In addition, the youth, teacher, and caretaker completed the Child Behavior Checklist (CBCL). The results indicated significant correlations across the teacher and caretaker for externalizing types of problems. The youth report form of the CBCL did not correspond to either adult informant. However, the ratings by the teacher and caretaker were related to externalizing types of problems, primarily hyperactivity/inattention, derived from the structured interview with the delinquent. The results suggest that, in the psychological assessment of incarcerated juvenile delinquents, agreement across informants is dependent on multiple factors, including type of behavior assessed and the approach utilized in assessment.This work was supported, in part, by the Juvenile Justice Coordinating Council of Georgia, the Office of Juvenile Justice and Delinquency Prevention, and the University of Georgia's Institute for Behavioral Research.