Answer:
[tex]t=\frac{r \sqrt{n-2}}{\sqrt{1-r^2}}[/tex]
And is distributed with n-2 degreed of freedom. df=n-2=12-2=10
The significance level is [tex]\alpha=0.01[/tex] and [tex]\alpha/2 = 0.005[/tex] and for this case we can find the critical values and we got:
[tex] t_{\alpha/2}= \pm 3.169[/tex]
Step-by-step explanation:
In order to test the hypothesis if the correlation coefficient it's significant we have the following hypothesis:
Null hypothesis: [tex]\rho =0[/tex]
Alternative hypothesis: [tex]\rho \neq 0[/tex]
The statistic to check the hypothesis is given by:
[tex]t=\frac{r \sqrt{n-2}}{\sqrt{1-r^2}}[/tex]
And is distributed with n-2 degreed of freedom. df=n-2=12-2=10
The significance level is [tex]\alpha=0.01[/tex] and [tex]\alpha/2 = 0.005[/tex] and for this case we can find the critical values and we got:
[tex] t_{\alpha/2}= \pm 3.169[/tex]