A researcher wants to test a hypothesis according to which the mean rating of guilt will be higher for unattractive defendants than for attractive defendants. The appropriate statistical test would be the _____.
A)Pearson r
B)two-tailed t-test
C)one-tailed t-test
D)chi-square

Question

Quizplus · Accepted Answer

Since the hypothesis predicts a directional difference (i.e. that the mean rating of guilt will be higher for unattractive defendants), the appropriate test would be a one-tailed t-test. The other options, Pearson r and chi-square, are not appropriate for testing differences in mean ratings. A two-tailed t-test could also be used, but it would be less powerful in detecting the predicted effect.

A Researcher Wants to Test a Hypothesis According to Which