Mary, a colleague of yours, wants to test the effectiveness of a new lesson plan on two different groups of students. She wants
to perform a t-test, but she is not sure whether to use a paired or unpaired test. Base on the information provided, how would you advise your colleague?
t-tests are essentially tests carried out to compare two different groups to check if there is a major difference in their performances or results which may be related in certain characteristics.
A paired (correlated) t-test is used when there are matched pair of similar units or instances of repeated measurements.
In this case, Mary has to use a paired t-test because the samples (students) have high similarity in characteristics. The students in question has to be from the same class to test her hypothesis (similar characteristics).
