If a correlated-groups t test and an independent-groups t test both have df=16, which experiment used more participants?
A)They both used the same number of participants (n=18).
B)They both used the same number of participants (n=17).
C)The correlated-groups t test used more participants.
D)The independent-groups t test used more participants.

Question

If a correlated-groups t test and an independent-groups t test both have df=16, which experiment used more participants?​
A)They both used the same number of participants (n=18).
B)They both used the same number of participants (n=17).
C)The correlated-groups t test used more participants.
D)The independent-groups t test used more participants.

Quizplus · Accepted Answer

The independent-groups t test used more participants because it assumes two independent groups, while the correlated-groups t test assumes a single group measured twice, leading to a smaller sample size. Therefore, if both have the same degrees of freedom, the independent-groups t test must have had a larger sample size.

If a Correlated-Groups T Test and an Independent-Groups T Test