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 variance of bond A is greater than 3.24%,
which of the following conclusion is least appropriate (significant level=5%) ?
选项:
A.It is appropriate to use the F-test.
B.The hypothesis is :
C.It is appropraite to use the chi-square test.
解释:
A is correct.
The chi-square test is used to test hypotheses concerning a single population variance.
The null hypothesis can place in whatever you want to reject, so B is correct.
卡方检验是检验总体的方差是否等于一个确定的值
本题中说的是检验均值是否大于26%,
因此H0:X均值≤26%,Ha:X均值>26%
像这种,原假设是小于等于,也算一个确定的值?只要原假设带等于号,就可以用卡方检验?