Rp-Rb算出来以后，波动率怎么算

为什么在CAPM模型算出来的，与实际相比，实际大就是低估了n而债券模型算出来的，与实际比，实际大就是高估了

还是不明白这道题的思路

老师您好，请问图片1里面的公式怎么变化成图片2那样去实际运用的？图片1公式的实际运用没看懂，谢谢！

模拟二 第54题 F-test和F-statistic 有什么区别？F-test老师已经在题目中解释了 是在假设检验中用来说检验总体自变量对因变量的解释程度的 那F-statistic呢？

c为什么对

这题是怎么做出来的 In a metal fabrication process, metal rods are produced that have an average length of 20.5 metres with a standard deviation of 2.3 metres. A quality control specialist collects a random sample of 30 rods and measures their lengths. 问题Suppose the resulting sample mean is 19.5 metres. Do you think that this sample result is unusually small? Explain. 答案：We have a random sample of metal rods drawn from a much larger population. A sample mean of only 19.5 metres is about 2.38 standard deviations below what we expect. The sample mean of 19.5 metres is unusually small.

In a metal fabrication process, metal rods are produced that have an average length of 20.5 metres with a standard deviation of 2.3 metres. A quality control specialist collects a random sample of 30 rods and measures their lengths. 问题：Suppose the resulting sample mean is 19.5 metres. Do you think that this sample result is unusually small? Explain. 答案：We have a random sample of metal rods drawn from a much larger population. A sample mean of only 19.5 metres is about 2.38 standard deviations below what we expect. The sample mean of 19.5 metres is unusually small. 老师我想请问这个题的答案怎么出来的，2.38这个数字怎么来的

老师好，第10题，为什么老师讲的和答案解析又有出入，到底是K-F还是F-K啊

正态分布的单尾和双尾对应的分位点重点的几个，没有记住，怎么办，总是混淆，还有就是VAR是单尾是么？