Mike concluded that there were no differences in self-confidence between those who had received his intervention and those in the control group. However, there were differences. Mike's intervention did work! Mike's conclusion represents
A) a Type I error.
B) a Type II error
C) both a Type I and Type II error.
D) neither a Type I or Type II error.

Question

Quizplus · Accepted Answer

Mike's conclusion that there were no differences in self-confidence between the intervention and control groups when there actually were differences represents a Type II error. This means that Mike failed to reject the null hypothesis when the alternative hypothesis was actually true.

Mike Concluded That There Were No Differences in Self-Confidence Between