Explain why we are able to compute many different values of β, the probability of a Type II error, for a single hypothesis test.
9.78 Explain what is meant by
a A serious Type II error.
b The power of a statistical test.
9.79 In general, do we want the power corresponding to a serious Type II error to be near 0 or near 1? Explain.
METHODS AND APPLICATIONS
9.80 Again consider the Consolidated Power waste water situation. Remember that the power plant will be shut down and corrective action will be taken on the cooling system if the null hypothesis H0: μ ≤ 60 is rejected in favor of Ha: μ > 60. In this exercise we calculate probabilities of various Type II errors in the context of this situation.
a Recall that Consolidated Power’s hypothesis test is based on a sample of n = 100 temperature readings and assume that σ equals 2. If the power company sets α = .025, calculate the probability of a Type II error for each of the following alternative values of μ: 60.1, 60.2, 60.3, 60.4, 60.5, 60.6, 60.7, 60.8, 60.9, 61.
b If we want the probability of making a Type II error when μ equals 60.5 to be very small, is Consolidated Power’s hypothesis test adequate? Explain why or why not. If not, and if we wish to maintain the value of α at .025, what must be done?