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This investigation was undertaken in an effort to establish physiological characteristics of soccer players and to relate them to positional roles. A total of 135 footballers (age 24.4 +/- 4.6 years) were assessed for body mass, % body fat, haemoglobin, maximal oxygen uptake (VO2 max), leg power, anaerobic capacity and speed prior to an English league season. The sample included 13 goalkeepers, 22 full-backs, 24 centre-backs, 35 midfield players and 41 forwards. The goalkeepers were significantly heavier (86.1 +/- 5.5 kg; P < 0.01) than all groups except the centre-backs, had significantly higher estimated body fat percentages than centre-backs, forwards, midfield players (P < 0.01) or full-backs (P < 0.05), significantly lower estimated VO2 max values (56.4 +/- 3.9 ml kg-1 min-1; P < 0.01) and were slowest over 60 m (12.71 +/- 0.42 s). The midfield players had the highest predicted VO2 max values (61.4 +/- 3.4 ml kg-1 min-1), this being significantly greater (P < 0.05) than for the centre-backs. The forwards were the fastest group over 60 m (12.19 +/- 0.30 s), being significantly quicker than goalkeepers or centre-backs (P < 0.01) and full-backs (P < 0.05). Anaerobic power, as well as knee extensor torques (corrected for body mass) and extensor-flexor ratios, were similar between groups. No difference in estimated body fat percentage was observed between any of the outfield players, and haemoglobin concentrations were similar among players of all positions.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Determining the Value of Cultural Goods: How Much (or How Little) Does Contingent Valuation Tell Us? 总被引:1,自引:0,他引:1
David Throsby 《Journal of Cultural Economics》2003,27(3-4):275-285
Contingent valuation methods (CVM) are now well established as a means of measuring the nonmarket demand for cultural goods and services. When combined with valuations provided through market processes (where relevant), an overall assessment of the economic value of cultural commodities can be obtained. Within a neoclassical framework, such assessments are thought to provide a complete picture of the value of cultural goods. But are there aspects of the value of cultural goods which are not fully captured, or not captured at all, within such a model? This paper argues that CVM provides an incomplete view of the nonmarket value of cultural goods, and that alternative measures need to be developed to provide a fuller account. 相似文献
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Richard A. Epstein 《Journal of Cultural Economics》2003,27(3-4):259-274
Ordinary markets allow parties, not the state, to value property and projects. But they do not account for subjective value in such traditional contexts as condemnation. An awareness of these nonmarket values helps overcome any categorical opposition to the use of the contingent valuation method (CVM) to value cultural and environmental resources. But accurate CVM should measure all values, positive or negative, tononowners; it should apply generally to any substitute projects; and it should seek to account for diminishing marginal value of additional resource units. CVM should be used only to aggregate nonmarket preferences, not to skew the political debate to cultural or environmental objectives. 相似文献
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The purpose of this study was to determine test-retest reliability for the 1-mile, 3/4-mile, and 1/2-mile distance run/alk tests for children in Grades K-4. Fifty-one intact physical education classes were randomly assigned to one of the three distance run conditions. A total of 1,229 (621 boys, 608 girls) completed the test-retests in the fall (October), with 1,050 of these students (543 boys, 507 girls) repeating the tests in the spring (May). Results indicated that the 1-mile run/walk distance, as recommended for young children in most national test batteries, has acceptable intraclass reliability (.83 less than R less than .90) for both boys and girls in Grades 3 and 4, has minimal (fall) to acceptable (spring) reliability for Grade 2 students (.70 less than R less than .83), but is not reliable for children in Grades K and 1 (.34 less than R less than .56). The 1/2 mile was the only distance meeting minimal reliability standards for boys and girls in Grades K and 1 (.73 less than R less than .82). Results also indicated that reliability estimates remained fairly stable across gender and age groups from the fall to spring testing periods, with the exception of the noticeably improved values for Grade 2 students on the 1-mile run/walk test. Criterion-referenced reliability (P, percent agreement) was also estimated relative to Physical Best and Fitnessgram run/walk standards. Reliability coefficients for all age group standards were acceptable to high (.70 less than P less than .95), except for Fitnessgram standards for 5-year-old girls on the 1-mile test for both fall and spring and for 6-year-old boys and girls on the 1-mile test administered in the spring. 相似文献
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