2011 Mock Afternoon Session Q20
The following ten observations are a sample drawn from a normal population: 25, 20, 18, -5, 35, 21, -11, 8, 20, 9. The fourth quintile (80th percentile) of the sample is closest to:
A. 8.0
B. 21.0
C. 24.2
答案里面选B，说21是eighth largest number. 但是根据Notes里面讲的， 应该是Ly=(10+1)*80/100=8.8
然后是eighth largest number plus 0.8 * (distance between 8th and 9th largest number).
这个题是不是错了？大家的看法哪？ |
发表于 2011-12-1 15:14
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