NO.PZ2015120604000136
问题如下:
Suppose a hypothesis test with a 5% significant level. What is the critical value of a z-statistic if it is a two-tailed test?
选项:
A.
±1.65
B.
±1.96.
C.
+1.96
解释:
B is correct.
A two-tailed z-test at a 5% significant level means the critical value is z=-1.96 or z=+1.96.
双尾检验应该是有两个值,为啥只要正的