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标题: 求助胡老师! [打印本页]

作者: FORPAN    时间: 2007-3-23 11:19     标题: 求助胡老师!

胡老师,您好!您在假设检验(B)讲义中的习题10,您说B答案没有道理,可是我不知道自己错在什么地方,我觉得B和D都正确。因为一类错误的概率为5%,我理解就是假设统计量(双尾假设)落在两个临界值之间的概率为95%,意味着置信区间为95%。

如果B的表述有误,怎么修改可以把我理解的这个意思表述出来?拜托老师

 题目如下:

For a hypothesis test with a probability of a tape II error of 60% and a probability of a tape I error of 5%, which of the following is ture:

B)There is a 95% probability that the test statistic will be between the critical value if this is a two-tailed test.

D)There is a 5% probability that the null hypothesis will be rejected when actually true , and the probability of rejecting the null when it is false is 40%.

B)There is a 95% probability that the test statistic will be between the critical value if this is a two-tailed test.

D)There is a 5% probability that the null hypothesis will be rejected when actually true , and the probability of rejecting the null when it is false is 40%.


作者: 胡老师    时间: 2007-3-25 08:32

a 5% probability 的理解应该是零假设本身是正确的,即不能拒绝零假设,但是实际上拒绝了的概率。注意,在假设检验中,我们不能说接受零假设,而只能说在多少概率下,不能拒绝零假设。B的陈述是接受零假设的陈述




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