问题如下：
2. Are the intercept term and the slope coefficient statistically significantly different from zero at the 5% significance level?
Give the t-critical values as follow:
the t-critical values are all two-tails
选项：
Intercept term significant?
Slope coefficient significant?
Yes
No
No
No
No
Yes
Yes
Yes
解释：
C is correct
考点：Hypothesis Test in Linear Regression
解析：因为是48个月的数据，所以n=48，所以本题应该去查双尾95%的df=48-2=46的数据，即 the critical two-tailed 95% t-value = 2.013.
截距项的 t检验值=0.0053/0.0042=1.262<2.013，斜率项的t检验值=1.5863/0.0744=21.32>2.013 所以，截距项不显著，斜率项显著
由第一小问得到，b0的95%的置信区间是 (-0.0032, 0.01375)。第二小问中看bo是否显著，答案里比较的是t统计量和CV值的大小，能通过判断bo的t-statistic是否在CI内来看显著性吗？晕晕的…额
