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Björn Öckert 《Economics of Education Review》2010,29(4):504-516
This paper exploits discontinuities and randomness in the college admissions in Sweden in 1982, to estimate the economic return to college in the 1990s. At the time, college admissions were highly selective and applicants were ranked with respect to their formal merits. Admissions were given to those ranked higher than some threshold value. At the margin, applicants were sometimes randomly assigned to college. Exploiting this Regression-Discontinuity design, individuals who were admitted in 1982 are estimated to have about 0.20 years longer college education in 1996. However, the earnings effects for applicants at the margin of admission are insignificant. Controlling for the college admission determinants, the OLS-estimates of the return to college is 1.4 percent in 1991–96. The IV-estimates are not significantly different from the OLS counterparts. 相似文献
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The aim of this study was to determine the physiological responses to orienteering by examining the interrelationships between the information provided by a differential global positioning system (dGPS) about an orienteer's route, speed and orienteering mistakes, portable metabolic gas analyser data during orienteering and data from incremental treadmill tests. Ten male orienteers completed a treadmill threshold test and a field test; the latter was performed on a 4.3 km course on mixed terrain with nine checkpoints. The anaerobic threshold, threshold of decompensated metabolic acidosis, respiratory exchange ratio, onset of blood lactate accumulation and peak oxygen uptake (VO2peak) were determined from the treadmill test. Time to complete the course, total distance covered, mean speed, distance and timing of orienteering mistakes, mean oxygen uptake, mean relative heart rate, mean respiratory exchange ratio and mean running economy were computed from the dGPS data and metabolic gas analyser data. Correlation analyses showed a relationship between a high anaerobic threshold and few orienteering mistakes (r = - 0.64, P < 0.05). A high threshold of decompensated metabolic acidosis and VO2peak were related to a fast overall time (r = -0.70 to -0.72, P < 0.05) and high running speed (r = 0.64 to 0.79, P < 0.05 and P < 0.01, respectively), and were thus the best predictors of performance. 相似文献
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