米妮涵 · 2021年08月06日
* 问题详情，请 查看题干
NO.PZ201709270100000107
问题如下：
7. The upper bound for the 95% confidence interval for the coefficient on the debt ratio in the regression is closest to:
选项：
A.−1.0199.
B.−0.3947.
C.1.4528.
解释：
B is correct.
The calculation for the confidence interval is −4.1589 ± (2.011 ×1.8718). The upper bound is −0.3947. The 2.011 is the critical t-value for the 5% level of significance (2.5% in one tail) for 48 degrees of freedom.
95%的置信区间那个critical value为什么不是1.96
NO.PZ201709270100000107 请问此题在哪个条件中体现了95%的 “T” 统计量呢？
NO.PZ201709270100000107 老师，我记得前面有一个类似的题目求置信区间，用的是mean加上t*stanrerror，就是用0.3979+t*stanrerror，为什么这里就直接用系数的估计值？
−0.3947. 1.4528. B is correct. The calculation for the confinintervis −4.1589 ± (2.011 ×1.8718). The upper bounis −0.3947. The 2.011 is the critict-value for the 5% level of significan(2.5% in one tail) for 48 grees of freem.这道题的2.011是如何得到的？
−0.3947. 1.4528. B is correct. The calculation for the confinintervis −4.1589 ± (2.011 ×1.8718). The upper bounis −0.3947. The 2.011 is the critict-value for the 5% level of significan(2.5% in one tail) for 48 grees of freem.为啥不能用1.96？
