Question

A researcher matched 30 participants on intelligence (hence 15 pairs of participants), and then compared differences in emotional responsiveness to two experimental stimuli between each pair. For this test, what are the critical values, assuming a two-tailed test at a 0.05 level of significance?

Answer 1

The critical value is ±2.145

Explanation:

Consider the provided information.

A researcher matched 30 participants on intelligence (hence 15 pairs of participants).

That means the value of n is 15.

Now find the degree of freedom as:
`df=n-1`

Therefore,

`df=15-1=14`

It is given that assuming a two-tailed test at a 0.05 level of significance.

α=0.05

`(\alpha)/(2)=(0.05)/(2)=0.025`

Now by using t distribution table the critical value is:

`\pm t_{(\alpha)/(2),df}=\pm t_(0.025,14)\\\pm t_(0.025,14)\approx\pm2.145`

Hence, the critical value is ±2.145