Active nuclear power plants. Refer to the U.S. Energy

QUESTION:

Active nuclear power plants. Refer to the U.S. Energy Information Administration’s list of active nuclear power plants operating in each of a sample of 20 states, Exercise 2.54 (p. 73). The data are reproduced in the next table.

a. Is there sufficient evidence to claim that the mean number of active nuclear power plants operating in all states exceeds 3? Test using \(\alpha\) = .10.

b. Are the conditions required for a valid small-sample test reasonably satisfied? Explain.

c. Eliminate the lowest two values and the highest two values from the data set, then conduct the test of part a on the smaller data set. What impact does this have on the test results?

d. Why is it dangerous to eliminate data points in order to satisfy an assumption for a test of hypothesis?