If a test of hypothesis has a Type I error probability (α) of 0.01, we mean
A) if the null hypothesis is true, we don't reject it 1% of the time.
B) if the null hypothesis is true, we reject it 1% of the time.
C) if the null hypothesis is false, we don't reject it 1% of the time.
D) if the null hypothesis is false, we reject it 1% of the time.

Question

Quizplus · Accepted Answer

Type I error is the probability of rejecting a true null hypothesis. Therefore, if the α level is 0.01, we reject the null hypothesis when the probability of the observed result occurring by chance is less than 1% (0.01). Hence, if the null hypothesis is true, we reject it 1% of the time.

If a Test of Hypothesis Has a Type I Error