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141.
James B. Connelly 《Psychology in the schools》1983,20(3):271-275
This study investigated patterns of Bannatyne's recategorized WISC-R scores of 146 predominantly Tlingit Indian children who were referred for psychoeducational testing. The students were divided into two groups, ages 6 through 10 and 11 through 16, in order to investigate patterns that occurred at each level and to investigate the proportions that exhibited a typically “Indian” pattern: Spatial > Sequential > Conceptual and Acquired Knowledge. As a group, the older children displayed an Indian pattern, but the younger children displayed a different one: Spatial > Conceptual and Sequential > Acquired Knowledge. Both groups, however, displayed a significantly greater proportion of children with an Indian pattern than would be expected by chance. A considerable number of individuals from both groups attained significant differences among scores in the Indian direction. 相似文献
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144.
We use prices realized for Picasso prints at auctions worldwide, as well as the 100 prints that comprise his Vollard Suite,
to test the law of one price: the proposition that identical art objects sold contemporaneously should command the same price
regardless of the auction house or geographic region where the sale takes place. Picasso is the most prolific printmaker of
the twentieth century and, from 1977 to 2004, his prints appreciated in price significantly faster than the prints of modern
masters as a whole. We find that Picasso prints sold in the United States command higher prices than in Europe. However, prices
realized at Sotheby’s in New York are no longer higher than at Christie’s in New York, nor at Kornfeld than at other auction houses. We find evidence of “irrational exuberance”
in the transitory nature of the extraordinary prices realized for the Picasso prints included in the 1997 sale of the collection
of Victor and Sally Ganz at Christie’s in New York. More generally, we find substantial noise in auction outcomes, a result
well known to savvy auction goers.
相似文献
Pauline M. Shum (Corresponding author)Email: |
145.
The aim of this study was to compare optimization and correction procedures for the determination of peak power output during friction-loaded cycle ergometry. Ten male and 10 female sports students each performed five 10-s sprints from a stationary start on a Monark 864 basket-loaded ergometer. Resistive loads of 5.0, 6.5, 8.0, 9.5, and 11.0% body weight were administered in a counterbalanced order, with a recovery period of 10 min between sprints. Peak power was greater and occurred earlier, with less work having been done before the attainment of peak power, when the data were corrected to account for the inertial and frictional characteristics of the ergometer. Corrected peak power was independent of resistive load (P > 0.05), whereas uncorrected peak power varied as a quadratic function of load (P < 0.001). For males and females, optimized peak power (971 +/- 122 and 668 +/- 37 W) was lower (P < 0.01) than either the highest (1074 +/- 111 and 754 +/- 56 W respectively) or the mean (1007 +/- 125 and 701 +/- 45 W respectively) of the five values for corrected peak power. Optimized and mean corrected peak power were highly correlated both in males (r = 0.97, P < 0.001) and females (r = 0.96, P < 0.001). The difference between optimized and mean corrected peak power was 37 +/- 30 W in males and 33 +/- 14 W in females, of which approximately 15 W was due to the correction for frictional losses. We conclude that corrected peak power is independent of resistive load in males and females. 相似文献
146.
Traditionally, it has been assumed that during middle-distance running oxygen uptake (VO2) reaches its maximal value (VO2max) providing the event is of a sufficient duration; however, this assumption is largely based on observations in individuals with a relatively low VO2max. The aim of this study was to determine whether VO2max is related to the VO2 attained (i.e. VO2peak) during middle-distance running on a treadmill. Fifteen well-trained male runners (age 23.3 +/- 3.8 years, height 1.80 +/- 0.10 m, body mass 76.9 +/- 10.6 kg) volunteered to participate in the study. The participants undertook two 800-m trials to examine the reproducibility of the VO2 response. These two trials, together with a progressive test to determine VO2max, were completed in a randomized order. Oxygen uptake was determined throughout each test using 15-s Douglas bag collections. Following the application of a 30-s rolling average, the highest VO2 during the progressive test (i.e. VO2max) was compared with the highest VO2 during the 800-m trials (i.e. VO2peak) to examine the relationship between VO2max and the VO2 attained in the 800-m trials. For the 15 runners, VO2max was 58.9 +/- 7.1 ml x kg(-1) x min(-1). Two groups were formed using a median split based on VO2max. For the high and low VO2max groups, VO2max was 65.7 +/- 3.0 and 52.4 +/- 1.8 ml x kg(-1) x min(-1) respectively. The limits of agreement (95%) for test-retest reproducibility for the VO2 attained during the 800-m trials were +/- 3.5 ml x kg(-1) x min(-1) for a VO2peak of 50.6 ml x kg(-1) x min(-1) (the mean VO2peak for the low VO2max group) and +/- 2.3 ml x kg(-1) x min(-1) for a VO2peak of 59.0 ml x kg(-1) x min(-1) (the mean VO2peak for the high VO2max group), with a bias in VO2peak between the 800-m runs (i.e. the mean difference) of 1.2 ml x kg(-1) x min(-1). The VO2peak for the 800-m runs was 54.8 +/- 4.9 ml x kg(-1) x min(-1) for all 15 runners. For the high and low VO2max groups, VO2peak was 59.0 +/- 3.3 ml x kg(-1) x min(-1) (i.e. 90% VO2max) and 50.6 +/- 2.0 ml x kg(-1) x min(-1) (i.e. 97% VO2max) respectively. The negative relationship (-0.77) between VO2max and % VO2max attained for all 15 runners was significant (P = 0.001). These results demonstrate that (i) reproducibility is good and (ii) that VO2max is related to the %VO2max achieved, with participants with a higher VO2max achieving a lower %VO2max in an 800-m trial on a treadmill. 相似文献
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148.
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
149.
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
150.
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