问题如下:
Here is a table discribing sample statistics from two bonds' rate of return which are both normally distributed over the past decades. If an investor is considering whether the mean of bond B is greater than 26%,
which of the following conclusion is least appropriate (significant level=5%) ?
选项:
A.It is approptiate to use the Z-test.
B.The mean of bond B is not significant greater than 26%.
C.It is a one-tailed test.
解释:
B is correct.
It is appropraite to ues the one-tailed Z-test because the sample size of bond B is bigger than 30.
The null hypothesis is: ≤
The test statistic:
α= 5% indicates the critical value is equal to ±1.65.
Because 1.91>1.65, therefore, we should reject the null hypothesis.
老师你好,这道题我用的排除法因为normal distribution所以可以用Z,然后就是题干中说greater than 26%,那么就是单尾所以选B,不知道我这个理解的思路和做这道题的思路对不对呢,还是要进行计算来得出这道题的答案,谢谢