If the p level is.0.05 and the null hypothesis is true, the probability of making a Type I error when performing a single hypothesis test is _____, but if three hypothesis tests are performed, then the probability of NOT making a Type I error is _____, which means that the probability of making a Type I error at least once in these three hypothesis tests is _____.
A) 0.05; 0.857; 0.143
B) 0.95; 0.85; 0.15
C) 0.05; 0.95; 0.15
D) 0.00; 0.95; 0.85

Question

Quizplus · Accepted Answer

The probability of making a Type I error in a single hypothesis test is 0.05. For three independent tests, the probability of NOT making a Type I error in all three is (1 - 0.05)^3 = 0.857375. Therefore, the probability of making at least one Type I error is 1 - 0.857375 = 0.142625, which rounds to 0.143.

If the P Level Is