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241.
An evaluation is offered of one of the Government's measures to alleviate youth unemployment-the Work Experience Programme (WEP). In a small-scale study conducted in Essex, most of the young people and employers involved in the scheme thought that its benefits considerably outweighed its disadvantages, and this view was shared by careers officers. The scheme helped the young participants to develop confidence in themselves and in their working potential, although at the same time it made them anxious about their ability and/or opportunity to continue this development. As a short-term response to youth unemployment, WEP has considerable value. Without certain improvements, however, it is not adequate for dealing with long-term structural unemployment.  相似文献   
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Assessment of children's adaptive behavior has been recommended for full multidimensional and nondiscriminatory evaluations. Additionally, previous research has reported discrepancies between teacher and parent reports on adaptive behavior. The purpose of this study was to compare mother and teacher reports on two scales from the Adaptive Behavior Inventory for Children of the System of Multicultural and Pluralistic Assessment (SOMPA). Black students from second through fourth grades (N = 24; 4 males and 4 females per grade) in an urban, parochial school were selected. The interviewers were two trained female graduate students (one white, one black). Each child's mother and teacher were interviewed in accordance with SOMPA assessment procedures. The results indicated that there was little agreement (.38 to .64) between mother and teacher reports. Additionally, mothers tended to provide higher ratings of adaptive behaviors than did teachers, irrespective of grade level. Implications of these findings for the assessment of children's adaptive behaviors are discussed.  相似文献   
244.
The assumption that the processing stages involved in sentence comprehension are serially and independently executed was tested in two separate experiments using two new sentence types. One experiment was a sentence-picture verification task, the other was not. In Experiment I, subjects viewed sentences such as It's false that the dots are red and indicated, by pressing the appropriate response key, which of two colors would make the sentence true. In Experiment II, subjects verified sentences such as It isn't true that the dots aren't red against pictures of colored dots. On the strength of Sternberg's additive factor method, present findings challenge the validity of the serial, independent stage assumption, and results are alternatively discussed in terms of a capacity sharing model.This research was supported by PHS research grant MH 23401 to Sam Glucksberg, principal investigator.  相似文献   
245.
Five experiments were conducted to assess the effects of several variables on the efficacy of feedback in reducing driving speed. Experiment 1 systematically varied the criterion used to define speeding, and results showed that the use of a lenient criterion (20 km/hr over the speed limit), which allowed for the posting of high percentages of drivers not speeding, was more effective in reducing speeding than the use of a stringent criterion (10 km/hr over the speed limit). In Experiment 2 an analysis revealed that posting feedback reduced speeding on a limited access highway and the effects persisted to some degree up to 6 km. Experiments 3 and 4 compared the effectiveness of an unmanned parked police vehicle (Experiment 3) and a police air patrol speeding program (Experiment 4) with the feedback sign and determined whether the presence of either of these enforcement variables could potentiate the efficacy of the sign. The results of both experiments demonstrated that although the two enforcement programs initially produced larger effects than the feedback sign, the magnitude of their effect attenuated over time. Experiment 5 compared the effectiveness of a traditional enforcement program with a warning program which included handing out a flier providing feedback on the number and types of accidents occuring on the road during the past year. This experiment demonstrated that the warning program produced a marked reduction in speeding and the traditional enforcement program did not. Furthermore, the warning program and a feedback sign together produced an even greater reduction in speeding than either alone.  相似文献   
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Stimulus generalization is suggested as an alternative method for examination of the "novelty" problem in motor learning. These experiments demonstrated that stimulus generalization occurs using simple movements as stimuli. The phenomenon of the "peak shift" in post-discrimination generalization gradients was also examined. The first experiment demonstrated that a peak shift occurred using linear movements as stimuli and that the magnitude of the peak shift increased as the difference between the training stimuli decreased. The second experiment showed similar results when the stimuli consisted of a range of movements rather than single movement length. The final experiment provided evidence that perception of movement length is influenced by the magnitude of an immediately preceding movement. The relevance of these studies to current motor-learning theory is discussed.  相似文献   
248.
The fixed-interval schedule of reinforcement is one of the more widely studied schedules in the experimental analysis of behavior and is also a common baseline for behavior pharmacology. Despite many intensive studies, the controlling variables and the pattern of behavior engendered are not well understood. The present study examined the microstructure and superstructure of the behavior engendered by a fixed-interval 5- and a fixed-interval 15-minute schedule of food reinforcement in the pigeon. Analysis of performance typical of fixed-interval responding indicated that the scalloped pattern does not result from smooth acceleration in responding, but, rather, from renewed pausing early in the interval. Individual interresponse-time (IRT) analyses provided no evidence of acceleration. There was a strong indication of alternation in shorter-longer IRTs, but these shorter-longer IRTs did not occur at random, reflecting instead a sequential dependency in successive IRTs. Furthermore, early in the interval there was a high relative frequency of short IRTs. Such a pattern of early pauses and short IRTs does not suggest behavior typical of reinforced responding as exemplified by the pattern found near the end of the interval. Thus, behavior from clearly scalloped performance can be classified into three states: postreinforcement pause, interim behavior, and terminal behavior.  相似文献   
249.
Excitability in a cortical representation of a foreleg was determined during elaboration of transswitching in dogs in three variations depending upon the stimulus used as a Conditioned stimulus (CS). If the flexor reaction to direct stimulation of the motor cortex was used as a CS, excitability changes of opposite signs appeared in the cortical representation of the foreleg, the threshold of flexion decreased in the alimentary situation and increased in the defense situation. Such changes in excitability were observed during instrumental conditioned transswitching. If subthreshold stimulation of the motor cortex was used as the CS, the threshold of flexion increased in both situations in approximately equal degree.  相似文献   
250.
Freud's term sekund?re Bearbeitung has been translated as both "secondary revision" and "secondary elaboration." In keeping with a distinction made by Silber (1973), the term secondary elaboration is used in this paper to indicate the process by which further dream modification occurs after dream recall in order to deepen the disguise of the manifest content for the analyst. Clinical cases are presented in an attempt to demonstrate the sole use of color for the alteration of dreams subsequent to their initial recall. Secondary elaboration in these cases is attributed to resistance to transference. Further, the clinical material indicates that the secondary elaboration simultaneously serves a communicative function.  相似文献   
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