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231.
A follow-up was made of the welfare payments received by AFDC clients who had received job-finding counseling. At the 6th-month follow-up, welfare payments had been reduced by about one-half for the Job Club clients vs 15% for the control group.  相似文献   
232.
Sixty children aged 2–3 to 5-2 were given four quantity tasks which tested their understanding of more and same. Two tasks involved addition, two involved judgment of static quantities. One of each type of task required a manipulative response, and one of each required a yes/no judgment. The tasks involved judgments of equality and inequality. Tasks involving a manipulative response were significantly easier than those involving a yes/no judgment, indicating that the nature of the response required of the child is crucial. All other differences were negligible, indicating that the other task variables investigated do not affect the child's ability to respond correctly. The ability to make accurate responses was not strongly associated with counting ability. There was a significant difference in the children's counting responses depending on the method used to elicit it.  相似文献   
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Duration of visible persistence in relation to range of spatial frequencies   总被引:1,自引:0,他引:1  
Five experiments examined the relationship between range of spatial frequencies contained in a visual display and duration of visible persistence. The high spatial frequency contents of the display were reduced by defocusing the image at the retina. Duration of visible persistence was measured by a task that required perceptual integration of a pattern whose parts were displayed sequentially in time. Experiments 1 and 2 showed that progressive reductions in the high-frequency contents of the display produced corresponding decrements in the duration of visible persistence. Experiments 3, 4, 5 showed that decrements in the duration of visible persistence could not be attributed to changes in the apparent size or in the brightness of the display brought about by defocusing. The results were interpreted in terms of the temporal response properties of perceptual mechanisms attuned to separate ranges of spatial frequencies. Strong parallels were drawn with the multichannel theory of visual information processing proposed by Breitmeyer and Ganz.  相似文献   
235.
Perception of dynamic events of American Sign Language (ASL) was studied by isolating information about motion in the language from information about form. Four experiments utilized Johansson's technique for presenting biological motion as moving points of light. In the first, deaf signers were highly accurate in matching movements of lexical signs presented in point-light displays to those normally presented. Both discrimination accuracy and the pattern of errors were similar in this matching task to that obtained in a control condition in which the same signs were always represented normally. The second experiment showed that these results held for discrimination of morphological operations presented in point-light displays as well. In the third experiment, signers were able to accurately identify signs of a constant handshape and morphological operations acting on signs presented in point-light displays. Finally, in Experiment 4, we evaluated what aspects of the motion patterns carried most of the information for sign identifiability. We presented signs in point-light displays with certain lights removed and found that the movement of the fingertips, but not of any other pair of points, is necessary for sign identification and that, in general, the more distal the joint, the more information its movement carries.  相似文献   
236.
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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238.
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   
239.
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   
240.
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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