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131.
A set of behavioral procedures focusing on the academic and social behavior problems of a group of adolescent students was incorporated within the context of a regular school program. The procedures, which involved manipulating type and delay of reinforcement, teaching desirable behaviors that were self-reinforcing or that others would readily reinforce, and training in several skills that are prerequisite to selfcontrol, were implemented in several classrooms through an independent grouporiented contingency system. These students performed significantly better than a matched control group with respect to grade-point average, class grades, school attendance, and length of time absent due to suspension. Changes in the contingency system throughout the year yielded differential effects on three behavioral measures: class attendance, assignments completed, and classroom behavior. The significance of these findings is discussed, and suggestions are made for future research efforts. 相似文献
132.
The effects that item order and basal and ceiling rules have on test means, variances, and internal consistency estimates for the PIAT mathematics and reading recognition subtests were examined. Seven items on the math subtest and one item on the reading recognition subtest were significantly easier or harder than their test placement indicated. The use of basal and ceiling rules had a pronounced effect on the means, variances, and reliabilities on the multiple choice math subtest, while the rules' effects on the reading recognition subtests were minor. Item order also affected scores on the math subtest. 相似文献
133.
Compared intrachild variability of five-year-old children (49 black, 34 white) on the Primary Mental Abilities Test when subjects reached their fifth birthday after completing at least two years of preschool enrichment. Conclusions, although qualified on the basis of limited sample size, revealed wider intrachild variability with minority children. This suggests that abandonment of testing may increase instructional problems and possibly lower the quality of instruction provided minority and poor children. 相似文献
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135.
This study used a multivariate approach and longitudinal design to examine the relationship of early perceptual and cognitive development to later school achievement. The extent to which a set of 4th-grade achievement measures could be predicted from a set of variables collected when the students were in first grade was determined through a series of canonical and multiple correlation analyses. These results were compared to results of an earlier phase of the study. Similarities between the two phases indicated that: (a) A measure of visual perception added significantly to the prediction of achievement afforded by consideration of sex and academic aptitude. (b) The variables used to predict achievement may differ somewhat between boys and girls. (c) The usefulness of sex as a predictor of school achievement depends upon the specific achievement area under consideration. Differences in the two phases involved the extent to which sex was a predictor of a specific achievement area. 相似文献
136.
Eighteen judges with backgrounds in assessment, decision making, and learning disabilities were asked to use an array of information to differentiate learning disabled and nonlearning disabled students. Each judge was provided with forms containing information on 42 test or subtest scores of 50 school-identified LD students and 49 non-LD students. Judges were extremely inaccurate in their classifications and in little agreement with each other. Also, it appeared that different judges emphasized different factors when making their decisions. The results suggest that, given current definitions of the condition called “learning disabilities,” there is considerable doubt that school personnel can accurately and reliably identify such students. 相似文献
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139.
Understanding the role of shaft stiffness in the golf swing 总被引:3,自引:3,他引:0
Theoretically, shaft stiffness can alter shot distance by increasing clubhead speed or altering clubhead orientation at impact.
A 3D forward dynamics model of a golfer and flexible club simulated the downswing. A genetic algorithm optimized the coordination
of the model’s muscles (four torque generators) to maximize clubhead speed. The maximum torque output and maximum rate of
torque development from the torque generators were varied to simulate the swing of golfers that generate different clubhead
speeds. Four shafts of varying stiffness (flexible, regular, stiff, and completely rigid) were entered into these simulations
to examine the role that shaft flexibility had on clubhead speed and orientation at impact. Shaft stiffness was found to have
a meaningful effect only on clubhead orientation (dynamic loft and dynamic close) at impact. There was no evidence to support
the premise that matching the stiffness properties of the shaft with the golfer would improve clubhead speed. 相似文献
140.
Dynamical analysis of winter terrain park jumps 总被引:1,自引:1,他引:0
Jump features in winter terrain parks frequently pose a hazard to patrons and may represent a significant liability risk to
winter resorts. By performing a simple dynamic analysis of terrain park jumps, the relative risk to impact injuries for any
proposed jump design can be quantified thereby allowing terrain park designers to minimize the risk from this class of injury. 相似文献