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891.
We evaluated a procedure for identifying potential reinforcers with profoundly retarded individuals. In Experiment 1, six persons were repeatedly exposed to 16 stimuli, and approach behaviors to each stimulus were used to identify preferred and nonpreferred stimuli. In Experiment 2, we examined the reinforcing properties of preferred and nonpreferred stimuli by delivering them contingently on the occurrence of arbitrarily selected responses. Results revealed that the preferred stimulus conditions typically produced higher rates of responding than did either the baseline or the nonpreferred stimulus conditions, suggesting that the procedure can be used to assess reinforcer value for individuals with limited behavioral repertoires.  相似文献   
892.
This study identifies the direct effects of objective job conditions on individual perceptions of job conditions. The assumptions that (1) group perceptions mediate the relationship between objective job conditions and individual perceptions of job conditions, and (2) group consensus enhances the relationship be-between group perceptions and individual perceptions were tested. Respondents were white, male, blue collar workers (N= 1240) in a tire and rubber manufacturing plant. Work groups (N= 156), consisting of four or more men on the same shift, in the same department, and who had the same supervisor, were identified. Objective job conditions included work group size, pay style, shift, and job technology. Group and individual perceptions of amount of work-load, role conflict, responsibility pressure, and intrinsic rewards were measured. The findings indicated that objective job conditions have important effects on individual perceptions of stressful and rewarding job conditions. Smaller work groups, and jobs that pay on an hourly rather than a piece-work basis, allow for some control over the pace of work, and allow for interaction among fellow workers resulted in higher levels of intrinsic rewards and lower levels of workload, role conflict, and responsibility pressures. An intriguing pattern appeared where, in perceptions involving interpersonal relations, work group influence was relatively more important than objective job conditions. When assessing task oriented aspects of work, objective job conditions were more important than group perceptions.  相似文献   
893.
894.
895.
This article illustrates the ways in which clients in career counseling think about the types of change in their career lives and about the determinants of change. It is based on an analysis of the interview data of a few adult clients. Two category systems are proposed as representative of the clients' thinking about change in these domains.  相似文献   
896.
We evaluated methods for comparing the effects of dextroamphetamine (Dexedrine), thioridazine (Mellaril), and contingency management in the control of severe behavior problems. A reversal design was used in which medications were systematically titrated and assessed in unstructured as well as structured settings with three clients. Subsequently, behavioral procedures including timeout, differential reinforcement of other behavior, and visual screening, were used in a multiple-baseline design across settings. The assessment and design methods were useful in comparing the interventions. Dextroamphetamine decreased inappropriate behaviors and improved academic behaviors in one client, but no reliable effects were observed in the other two clients. Thioridazine was variable across clients, settings, behaviors, and dosages. Contingency management produced consistent decreases in inappropriate behaviors and small improvements in academic performance.  相似文献   
897.
Tapping rate and variability were measured as 73 normal, right-handed children in Grades 1–4 engaged in speeded unimanual finger tapping with and without concurrent recitation. Speaking reduced the rate of tapping and increased its variability to a greater extent in younger children than in older children. Developmental changes in variability but not rate were attributable to a greater number of lengthy (>500 ms) pauses in the tapping of younger children. Speaking slowed the right hand more than the left, and the degree of this asymmetry was constant across grade levels. The right-hand effect for tapping rate was not attributable to lengthy pauses. In contrast, asymmetric increases in tapping variability occurred only among children in Grade 1 and only when lengthy pauses were included in the data. The results implicate three mechanisms of intertask interference: one involving capacity limitations, a second involving cross-talk between motor control mechanisms for speech and finger movement, respectively, and a third factor involving occasional diversion of attention from tapping to speaking. These mechanisms are discussed in relation to developmental changes in mental capacity.  相似文献   
898.
Subjects in Santa Barbara, California, and Groningen, The Netherlands, participated in a seven-person social dilemma game, presented in terms of a conservation of resources problem. Prior to their decision making in the social dilemma game, subject's social motive (altruistic, cooperative, individualistic, competitive) was assessed by means of two different classification procedures. On the basis of previous research findings American subjects were expected to display relatively more competitive social motives, and Dutch subjects relatively more cooperative ones. However, no indications of crosscultural differences were found neither with regard to the distribution of social motives nor with regard to the amount of resources taken for self in the social dilemma game. In both locations, competitive subjects took most resources for self, individualistic subjects took next most, cooperative subjects took less than individualists, and altruistic subjects took the least. In addition to predictive validity, indices of the convergent validity of two social motive assessment procedures were described.  相似文献   
899.
Two experiments investigated sentence context effects on the naming times of sentence completion words by third-grade children and college students. Across both experiments, the largest age difference in contextual facilitation was obtained for highly predictable, best completion words. Pronounced age differences in facilitation effects were also present for semantically acceptable target words which were much less predictable in the sentence context than the best completion words. However, age differences in contextual facilitation were negligible for target words which were associatively related to the best completion word, but which were not also semantically acceptable in the sentence context. Thus, the semantic acceptability of the word in the sentence context had a much greater influence on children's as compared to adults' word identification times, both when the word was highly predictable, as well as when it was much less predictable in the sentence context.  相似文献   
900.
The use of spelling-sound information in both reading and spelling was evaluated by having children read and spell nonwords and five types of words that differed in terms of their regularity for reading and spelling. The subjects were grade 3 children who had been psychometrically defined as good readers and good spellers (“good”), good readers and poor spellers (“mixed”), or poor readers and poor spellers (“poor”). Results indicated that all children attempted to use spelling-sound correspondences in both reading and spelling, although children in both the mixed and the poor groups had weaker knowledge of these correspondences and were less systematic in their use of them. Furthermore, even though the children in the mixed group had been matched with children in the good group on reading comprehension, the number and type of errors made by the mixed subjects on both the reading and spelling tasks were more similar to those of the poor subjects than to those of the good subjects.  相似文献   
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