t***e 发帖数: 446 | 1 A research company patented two tests, Test A and Test B, that measure
various aspects of athletic performance. (We know that both these tests take
into account the maximum aerobic capacity measured by VO2.)These two tests
are standardized to have the same distribution with mean 50 and standard
deviation 25.A large group of athletes takes the first test, and of these,
the top 75\% are selected to take second test. Do you expect this select
group to perform (on average): a) better; b) worse; c) the same as they
performed on the first test
我的想法是要看 measure 的这两个 aspects 是不是相关的。如果是uncorrelated, 那
应该 performance 一样吧。
谢谢大家指教。 | c******r 发帖数: 300 | 2 Depends on the correlation, if postive, note that taller fathers tend to
have sons that are not as tall ...
take
tests
【在 t***e 的大作中提到】 : A research company patented two tests, Test A and Test B, that measure : various aspects of athletic performance. (We know that both these tests take : into account the maximum aerobic capacity measured by VO2.)These two tests : are standardized to have the same distribution with mean 50 and standard : deviation 25.A large group of athletes takes the first test, and of these, : the top 75\% are selected to take second test. Do you expect this select : group to perform (on average): a) better; b) worse; c) the same as they : performed on the first test : 我的想法是要看 measure 的这两个 aspects 是不是相关的。如果是uncorrelated, 那 : 应该 performance 一样吧。
| c**********e 发帖数: 2007 | 3 Worse. The same only if their correlation is 1 -- this can be ruled out as
they are two different measures. |
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