Twenty participants are studied in a simple experiment. Then, 20 participants are studied in a matched pairs experiment. Relative to the simple experiment, the matched pairs experiment has
A) less power, fewer df
B) more power, fewer df
C) less power, more df
D) more power, more df

Question

Quizplus · Accepted Answer

Matched pairs experiments typically have more power because they control for variability between subjects by comparing each participant to themselves or a matched counterpart, reducing error variance. However, they have fewer degrees of freedom because the analysis is based on differences within pairs rather than individual scores.

Twenty Participants Are Studied in a Simple Experiment