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911.
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The purpose of this study was (a) to determine if a declassification occurs when estimated learning potential (ELP) is used in reevaluation of special education students and (b) to assess the effects of the use of ELP by multidisciplinary teams. Subjects included 107 black and 13 white students (83 males and 37 females) referred for reevaluation from classes for the mentally retarded. Data analysis consisted of determining the percentage of students who would be classified as mentally retarded according to the main criterion of (a) Wechsler Intelligence Scale for Children-Revised (WISC-R) scores, or (b) ELP scores, or (c) multidisciplinary teams' placement. A chi-square test of independence indicated a significant difference between WISC-R and ELP scores; and between multidisciplinary teams' placement and ELP scores (p<.05). Students already in special education classes for the mentally retarded were not determined to be ineligible for services by multidisciplinary teams, even though 15% of the students would be ineligible for services according to ELP scores.  相似文献   
913.
Rats obtained access to food twice each 24-hour period. The first session was a work session in which food was available on a progressive-ratio schedule. During the second session, which occurred between 1 and 23 hours after the work session, food was freely available up to a fixed total intake each 24 hours. The situation resembled elements of several real world circumstances, including the choice between continuing to forage in a rapidly depleting patch and waiting for a better patch, and between working now and receiving a guaranteed income later. The purpose of the experiment was to explore the time period over which future access to reward could affect current responding. Contrary to what might be expected from recent theorizing, anticipation of future food delayed by an hour or more after the start of the work session had no effect on current performance. Food intake was high and constant during work sessions except for a prefeeding effect that occurred when the free session closely preceded the next day's work session. Also, an increase in the difficulty of the work schedule increased the amount of work and the maximum price paid for food as if the work session were the only time food was available. The results indicate the importance of considering temporal limits in theories that require animals to integrate input over time to determine the allocation of resources among alternatives.  相似文献   
914.
The behavior-regulation approach to learned performance has been the subject of misapprehension and disagreement concerning: (1) the nature and importance of behavior regulation, (2) the definition and role of behavioral set-points, (3) the relation of optimal schedule performance to behavioral set-points, and (4) the question of whether deviations from total responding or from response patterns are the primary determinant of molar responding under schedule constraint. After clarifying the nature and role of behavior regulation and set-points, this paper shows that the data used to question optimal schedule performance (Allison, 1981a) actually strongly support the general behavior-regulation approach. These data also indicate a role for response-pattern set-points in determining schedule behavior, but contradict the hypothesis that deviations from response-pattern characteristics are the primary determinant of molar schedule effects.  相似文献   
915.
This study investigated the intellectual functioning and personality characteristics of 81 Australian ex-servicemen, 42 of whom had served in Vietnam. A Cognitive Impairment Model (SCIM) developed by Savage (1978, 1981, 1984) enabled intellectual functioning levels, intellectual deterioration and learning ability in the verbal and performance modalities to be asses. The Clinical Analysis Questionnaire (CAQ) of Krug (1980) based 00 Cattell's theory and personality measurement techniques provided an assessment of normal personality characteristics and clinical factors. The data suggested that the two groups, Australian ex-servicemen and Australian Vietnam veterans, were relatively homogeneous with regard to cognitive functioning and gave no indication of impairment in their intellectual levels or of their learning ability. Significant personality differences were, however, found between the two groups of ex-servicemen. The Vietnam veterans showed significantly more tension, depression, guilt, resentment, alienation and hypochondriasis than their colleagues who had remained in Australia. They were more withdrawn from others and from reality and had more abnormal thought than the ex-servicemen who had not been to Vietnam. The cognitive data do not support the view that Vietnam veterans suffered from any serious cognitive impairment. The personality data, however, suggest a significant “Psycbological Stress Syndrome” in these Vietnam veterans which required professional psychological treatment.  相似文献   
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Three studies compared the efficacy of various treatments for public-speaking incompetence. These effects were evaluated for the target behavior as well as for generalization effects across situations (conversations), settings (different sizes and types of audiences) and time (6-month follow-up). The first study showed that Self-instructional Training, either alone or in combination with other procedures, produced little or no benefits. The second study demonstrated the superiority of a Skills Training program over flooding therapy, while the final study failed to detect any enhancement of treatment benefits for the addition of home-practice to the Skills Training. In the first two studies generalization occurred across the three dimensions (settings, situations and time), while in the final study it was shown that the program was effective for a clinical population as well as recruited volunteers.  相似文献   
920.
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