Chapter 8.4（课件）- 《统计学基础（英文版）》同步教学（人民大学版）

Chapter Hypothesis Testing with Two Samples 8 1 Copyright 2019, 2015, 2012, Pearson Education, Inc. 1 Larson/Farber 6th ed Chapter 1 Chapter Outline 8.1 Testing the Difference Between Means (Independent Samples, 1 and 2 Known) 8.2 Testing the Difference Between Means (Independent Samples, 1 and 2 Unknown) 8.3 Testing the Difference Between Means (Dependent Samples) 8.4 Testing the Difference Between Proportions . 1 Copyright 2019, 2015, 2012, Pearson Education, Inc. Section 8.4 Testing the Difference Between Proportions . 1 Copyright 2019, 2015, 2012, Pearson Education, Inc. Section 8.4 Objectives How to perform a two-sample z-test for the difference between two population proportions p1 and p2 . 1 Copyright 2019, 2015, 2012, Pearson Education, Inc. Two-Sample z-Test for Proportions Used to test the difference between two population proportions, p1 and p2. Three conditions are required to conduct the test. The samples must be randomly selected. The samples must be independent. The samples must be large enough to use a normal sampling distribution. That is, n1p1  5, n1q1  5, n2p2  5, and n2q2  5. . 1 Copyright 2019, 2015, 2012, Pearson Education, Inc. Two-Sample z-Test for the Difference Between Proportions If these conditions are met, then the sampling distribution for , is a normal distribution Mean: A weighted estimate of p1 and p2 can be found by using Standard error: . 1 Copyright 2019, 2015, 2012, Pearson Education, Inc. A two-sample z-test is used to test the difference between two population proportions p1 and p2 when these conditions are met. The samples are random. The samples are independent. The quantities n1, n1, n2, and n2 are at least 5. The test statistic is The standardized test statistic is Two-Sample z-Test for the Difference Between Proportions . where 1 Copyright 2019, 2015, 2012, Pearson Education, Inc. Two-Sample z-Test for the Difference Between Proportions Verify that the samples are random and indepe