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小布的圈圈 · 2017年01月30日

问一道题：NO.PZ2015121802000021 [ CFA I ]

  1. CFA I

问题如下图：

    

选项：

A.

B.

C.

为什么答案是取得样本的方差而不是总体的方差？

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已采纳答案

maggie_品职助教 · 2017年01月30日

这是我的理解，供你参考：
总体指的是：统计研究的客观对象的全体
样本是从总体中抽取的一部分个体所组成集合
对于这题的方差计算，由于题目只给出了某项投资5年数据而且还是年数据，这5年的年化收益率对于总投资周期的收益率（总体）来说相当于一个样本，因此应当计算样本方差。








小布的圈圈 · 2017年02月11日

谢谢！！

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