Question

3. After completing a statistical analysis of a survey of 40 students, the principal

of North High School made the following conclusion: reject the null hypothesis;
there is convincing evidence that more than 50% of students support a schedule
change to have lunch occur earlier in the day. Which error could have been
committed?
(A) Type I error: Conclude that more than 50% of students want earlier lunch, when
50% or less want earlier lunch.
(B) Type l error: Conclude that more than 50% of students want earlier lunch, when
more than 50% want earlier lunch.
(0) Type Il error: Fail to reject that 50% of students want earlier lunch, when more than
50% want earlier lunch.
(D) Type Il error: Fail to reject that 50% of students want earlier lunch, when 50% or less
want earlier lunch.
(E) Type Il error: Fail to reject that more than 50% of students want earlier lunch, when
50% or less want earlier lunch.​

Answer 1

Option A

Explanation:

A type I error is committed when a researcher rejects the null hypothesis when it is actually true.

The null hypothesis is: U <= 50%

The alternative is: U > 50%

Thus, the principal could have committed an error by rejecting null hypothesis and concluding that more than 50% of students want earlier lunch, when in actuality 50% or less want earlier lunch.