Imagine that a study of memory and aging finds that younger participants correctly recall 55 percent of studied words, older participants correctly recall 42 percent of studied words, and the size of this effect is Cohen's d = 0.49.According to Cohen's conventions for interpreting d, this effect is:
A) small.
B) medium.
C) large.
D) so small as to be considered virtually no effect.

Question

Quizplus · Accepted Answer

Cohen's conventions define a d of 0.2 as a small effect, a d of 0.5 as a medium effect, and a d of 0.8 or above as a large effect. Therefore, a d of 0.49 is considered a medium effect.

Imagine That a Study of Memory and Aging Finds That