Critical Thinking Challenges The power of a test (1 - B) can be calculated when a Step 2 Using the value of X found in step 1 and the specific value of the mean is hypothesized in the alternative value of u in the alternative hypothesis, hypothesis; for example, let Ho: / = 50 and let H: p = 52. find the area corresponding to z in the To find the power of a test, it is necessary to find the value of B. This can be done by the following steps: formula z = X - H o/ Vn Step 1 For a specific value of a find the corresponding Step 3 Subtract this area from 0.5000. This is the value value of X, using = = = X -M where u is the of B. o/ Vn' hypothesized value given in Ho. Use a right-tailed Step 4 Subtract the value of B from 1. This will give you test. the power of a test. See Figure 8-41. 8-72 Answers to Applying the Concepts 485 1. Find the power of a test, using the hypotheses 2. Select several other values for y in H, and given previously and a = 0.05, o = 3, and compute the power of the test. Generalize the n = 30. results. FIGURE 8-41 Relationship Among a, B. and the Power of a Test A = 50 - 52