杨嘻嘻 · 2022年05月16日
NO.PZ2015120604000045
问题如下：
The table below shows the monthly stock returns of Ivy Corp.
According to the above table, calculate the median stock return for Ivy Corp.?
选项：
A.7.7%.
B.8.0%.
C.12.0%.
解释：
B is correct
Firstly, we rank the returns : 20% 12% 12% 4% 3% -5%.
As there are 6 observations, the median is the average of 12% and 4%
(12%+4%)/2=8%.
求median，数据个数是偶数，不应该=n+2 / 2=4 ?
NO.PZ2015120604000045问题如下 The table below shows the monthly storeturns of Ivy Corp.Accorng to the above table, calculate the mestoreturn for Ivy Corp.?A.7.7%.B.8.0%.C.12.0%.B is correctFirstly, we rank the returns : 20% 12% 12% 4% 3% -5%.there are 6 observations, the meis the average of 12% an4%(12%+4%)/2=8%.6个数，中位点是6+1=7/2=3.5中位数=4%+（12%-4%）*（3.5-3）=8%这种方法对吗？
me要先排序的吗，那为什么求frequency的mean不用排序，按照给定的柱状图的frequency来求了
为什么不是用分位数的公式？6乘以1/2=3.5，第三个数和第四个数是4和12，然后（12-4）乘以0.5，再加3，等于7，谢谢
排序也应该是从小到大排序吧，虽然结果是一样的？？
