Repeat the previous exercise, using lower? α = .05. For each true value of, is the power higher or lower?
For a certain wine, the mean pH (a measure of acidity) is supposed to be 3.50 with a known standard deviation of α = .10. The quality inspector examines 25 bottles at random to test whether the pH is too low, using a left-tailed test at α = .01.
(a) What is the power of this test if the true mean is α = 3.48?
(b) If the true mean is α = 3.46?
(c) If the true mean is α = 3.44?