Quality of Public Schools
Government critics were concerned that the quality of the public schools in their
community was poor, so they ran a study to compare school satisfaction of teachers
working private versus public schools in their community. The teachers’ school
satisfaction ratings they obtained are below (higher rating = greater satisfaction).
Teacher | Public School | Private School
A | 2 | 7
B | 4 | 8
C | 6 | 10
D | 8 | 8
E | 10 | 12
a. Assume these ratings represent samples of 5 randomly selected teachers from
each type of school (i.e., every score is from a different teacher). Use an appropriate
statistical test to assess whether public vs. private school satisfaction
ratings differ (use α = 0.05).
i. State the test you will use and why
ii. State your hypotheses (H1 & H0) and critical region
iii. Calculate the test statistic
iv. Interpret your findings
b. Now assume these ratings represent a sample of 5 randomly selected teachers
and each teacher is tested twice – once before and once after their school was
converted from public to private (i.e., pre-post). Use an appropriate statistical test
to assess whether public vs. private school satisfaction ratings differ (α = 0.05).
i. State the test you will use and why
ii. State your hypotheses (H1 & H0) and critical region
iii. Calculate the test statistic
iv. Interpret your findings
c. Compare your findings from these two tests (i.e., what do they allow you to
conclude. Do they differ or not, and why? Assess whether one test is better
than the other and explain your answer.
