A researcher wishes to see if there is a difference in the average number of times local police were called in school incidents. Samples of school districts were selected, and the numbers of incidents for a specific year were reported. At α = 0.05, is there a difference in the means? If so, suggest a reason for the difference.

If the null hypothesis is rejected, use the Scheffé test when the sample sizes are unequal to test the differences between the means, and use the Tukey test when the sample sizes are equal. Perform these steps.
a. State the hypotheses and identify the claim.
b. Find the critical value(s).
c. Compute the test value.
d. Make the decision.
e. Summarize the results, and explain where the differences in means are.
Use the traditional method of hypothesis testing unless otherwise specified.

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