Page 573 - Probability and Statistical Inference
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550    12. Large-Sample Inference

                                 for (p  - p ) with approximate confidence coefficient 1 − α.
                                      1   2
                                    Tests of Hypotheses for the Success Probability
                                    Let us first pay attention to the one-sample problems. With preassigned α
                                 ∈ (0, 1), we test a null hypothesis H  : p = p  with an approximate level α. The
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                                 specific alternative hypotheses will be given shortly. Here, 0 < p  < 1 is a
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                                 fixed. We consider the test statistic




                                 for large n when p = p .
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                                    Upper-Sided Alternative Hypothesis
                                    Here we test H  : p = p  versus H  : p > p . See, for example, the Figure
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                                 12.3.2. We can propose the following upper-sided approximate level a test:
                                    Lower-Sided Alternative Hypothesis
                                    Here we to test H  : p = p  versus H  : p < p . See, for example, the Figure
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                                 12.3.3. We can propose the following lower sided approximate level α test:
                                    Two-Sided Alternative Hypothesis
                                    Here we test H  : p = p  versus H  : p < p . See, for example, the Figure
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                                 12.3.4. We can propose the following two sided approximate level a test:

                                    Remark 12.3.2 In the case of the upper- or lower-sided alternative
                                 hypothesis, one should in fact prefer to use the corresponding randomized
                                 UMP tests discussed in Chapter 8 instead of the proposed approximate
                                 tests given by (12.3.23) and (12.3.24). On the other hand, when  n is
                                 large, finding the cut-off points for implementing the UMP test may be-
                                 come too cumbersome. Hence, the approximate tests in proposed (12.3.23)
                                 and (12.3.24) are also used in practice whenever n is large.
                                    Next, let us briefly address the two-sample problems. With preassigned
                                 α ∈ (0, 1), we test a null hypothesis H  : p  = p  with the approximate level
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                                                                  0
                                                                     1
                                 α. The specific alternative hypotheses will be given shortly. Under the null
                                 hypothesis  H  we have p  =  p  =  p where 0 <  p < 1 is unknown and
                                             0          1    2
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