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Ebook Statistics for business and economics (9th edition): Part 2

(BQ) Part 2 book "Statistics for business and economics" has contents: Analysis of variance, introduction to nonparametric statistics, additional topics in regression analysis, multiple variable regression analysis, two variable regression analysis,.and other contents. | www.downloadslide.com CHAP T E R C H A P T E R O U T LIN E 10 Two Population Hypothesis Tests 10.1 Tests of the Difference Between Two Normal Population Means: Dependent Samples Two Means, Matched Pairs 10.2 Tests of the Difference Between Two Normal Population Means: Independent Samples Two Means, Independent Samples, Known Population Variances Two Means, Independent Samples, Unknown Population Variances Assumed to Be Equal Two Means, Independent Samples, Unknown Population Variances Not Assumed to Be Equal 10.3 Tests of the Difference Between Two Population Proportions (Large Samples) 10.4 Tests of the Equality of the Variances Between Two Normally Distributed Populations 10.5 Some Comments on Hypothesis Testing Introduction In this chapter we develop procedures for testing the differences between two population means, proportions, and variances. This form of inference compares and complements the estimation procedures developed in Chapter 8. Our discussion in this chapter follows the development in Chapter 9, and we assume that the reader is familiar with the hypothesis-testing procedure developed in Section 9.1. The process for comparing two populations begins with an investigator forming a hypothesis about the nature of the two populations and the difference between their means or proportions. The hypothesis is stated clearly as involving two options concerning the difference. These two options are the only possible outcomes. Then a decision is made based on the results of a statistic computed from random samples of data from the two populations. Hypothesis tests involving variances are also becoming more important as business firms work to reduce process variability in order to ensure high quality for every unit produced. Consider the following two examples as typical problems: 1. An instructor is interested in knowing if assigning case studies increases students’ test scores in her course. To answer her question, she could first assign cases in one .