J********1
发帖数: 63 | 1 我觉得无法比较谁的分数高。
即使分布相同，随即抽取的样本也可能千差万别。
不知道我理解的对不对？
A large class of students takes part in two different exams, Exam A and Exam
B. It is known that the grades of the entire class for the two exams range
from 1 to 100 and have the same distribution. The students that ranked in
the top 25% on the first exam are selected, and this group's average grades
on the two exams are computed, GrA and GrB, respectively.
Which one should be greater: GrA or GrB ? | w*******9
发帖数: 1433 | 2 If it matters, E(Ga)>=E(Gb) |
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