We are about to test a hypothesis using data from a well-designed study. Which is true?
I. A small P-value would be strong evidence against the null hypothesis.
II. We can set a higher standard of proof by choosing $\alpha = 10 \% \text { instead of } 5 \%$
III. If we reduce the alpha level, we reduce the power of the test.
A) none of these
B) I only
C) III only
D) II only
E) I and III only

Question

Quizplus · Accepted Answer

A small P-value indicates strong evidence against the null hypothesis (I is true). Reducing the alpha level decreases the probability of rejecting the null hypothesis when it is false, thus reducing the power of the test (III is true).

We Are About to Test a Hypothesis Using Data from a Well-Designed