NO.PZ2022071202000084
问题如下:
Questiont-statistic for 24 degrees of freedom and at the 1% level of statistical significance = 2.807
Null hypothesis (H0): Mean difference of returns = 0
选项:
A.rejected because the computed test statistic exceeds 2.807. B.accepted because the computed test statistic exceeds 2.807. C.accepted because the computed test statistic is less than 2.807.解释:
Solution
A is correct.
In this case, the test statistic equals: (4.25-0)/(6.25/√25)= 3.40. Because 3.40 > 2.807, the null hypothesis that the mean difference is zero is rejected.
B is incorrect because a too large (or too small) test statistic leads to the rejection of the null hypothesis.
C is incorrect because the correctly computed test statistic exceeds the critical value of 2.807. A reasonable way to reach response C is to fail to divide the standard error by the square root of the sample size, erroneously using 4.25/6.25 = 0.68 as the test statistic.
我通过给出的两个标准差算t检验,表格第四行two independent populations和paired comparison有什么区别?