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哈桑哥 · 2017年02月21日

问一道题:NO.PZ2015121802000021 [ CFA I ]

问题如下图:

    

选项:

A.

B.

C.

为什么这个地方答案要除以n-1?

题目并没有说是样本标准差啊。。。

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已采纳答案

maggie_品职助教 · 2017年02月21日

只要题目没给出是总体,我们一般认为都是样本。因为我们并不知这项投资的总投资期和计算回报率的频率,仅选用其中5年的年数据,明显就是个样本。

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