NO.PZ201904080100007703
问题如下:
3. What is the width of the 99% confidence interval for AP, and is zero in that 99% confidence interval?
选项:
A.
B.
C.
D.
解释:
C is correct.
考点:多元回归分析
解析:这时候需要用t统计量,双尾1%相当于单尾0.5%,选择自由度为176的critical value是2.604,接受域是 7.4 +/- 5.4 * 2.604. 也就是-6.662到21.462,包含了0,宽度是28.124.
为什么用7.4,8.3不是ap的均值啊