Graduation Tests Many States Mandate Tests That Have to Be

Graduation tests Many states mandate tests that have to be passed in order for students to
graduate with a high school diploma. A local school superintendent believes that
after-school tutoring will improve the scores of students in his district on the state's
graduation test. A tutor agrees to work with 15 students for a month before the
superintendent will approach the school board about implementing an after-school
tutoring program. The after-school tutoring program will be implemented if student
scores increase by more than 20 points. The superintendent will test a hypothesis using α
0.02 .
a. Write appropriate hypotheses (in words and in symbols).
b. In this context, which do you consider to be more serious - a Type I or a Type II error?
Explain.
c. After this trial produced inconclusive results, the superintendent decided to test the
after-school tutoring program again with another group of students. Describe two changes
he could make in the trial to increase the power of the test, and explain the disadvantages
of each.