CHAPTER 11: Hypothesis Testing Involving two Sample means or Proportions to accompany Introduction to business statistics fourth edition, by ronald m. Weiers Presentation by priscilla Chaffe -Stengel Donald n. Stengel o 2002 The Wadsworth Group
CHAPTER 11: Hypothesis Testing Involving Two Sample Means or Proportions to accompany Introduction to Business Statistics fourth edition, by Ronald M. Weiers Presentation by Priscilla Chaffe-Stengel Donald N. Stengel © 2002 The Wadsworth Group
l Chapter 11-Learning objectives Select and use the appropriate hypothesis test In comparing Means of two independent samples Means of two dependent samples Proportions of two independent samples Variances of two independent samples Construct and interpret the appropriate confidence interval for differences in Means of two independent samples Means of two dependent samples Proportions of two independent samples o 2002 The Wadsworth Group
Chapter 11 - Learning Objectives • Select and use the appropriate hypothesis test in comparing – Means of two independent samples – Means of two dependent samples – Proportions of two independent samples – Variances of two independent samples • Construct and interpret the appropriate confidence interval for differences in – Means of two independent samples – Means of two dependent samples – Proportions of two independent samples © 2002 The Wadsworth Group
l Chapter 11-Key Terms Independent vs dependent samples Pooled estimate of the common varlance common standard deviation population proportion Standard error of the estimate for the difference of two population means difference of two population proportions Matched, or paired, observations Average difference o 2002 The Wadsworth Group
Chapter 11 - Key Terms • Independent vs dependent samples • Pooled estimate of the – common variance – common standard deviation – population proportion • Standard error of the estimate for the – difference of two population means – difference of two population proportions • Matched, or paired, observations • Average difference © 2002 The Wadsworth Group
l Independent us dependent samples Independent Dependent Samples: Samples Samples taken from two Samples taken from two populations where either different populations, (1) the element sampled is a member of both populations where the selection p or (2) the element sampled process for one sample is independent of the in the second population is selected because it is similar selection process for the on all other characteristics other sample or"matched, to th element selected from the first population o 2002 The Wadsworth Group
Independent vs Dependent Samples • Independent Samples: Samples taken from two different populations, where the selection process for one sample is independent of the selection process for the other sample. • Dependent Samples: Samples taken from two populations where either (1) the element sampled is a member of both populations or (2) the element sampled in the second population is selected because it is similar on all other characteristics, or “matched,” to the element selected from the first population © 2002 The Wadsworth Group
I Examples: Independent versus Dependent samples Independent Dependent Samples: Samples Testing a companys Testing the relative claim that its peanut fuel efficiency of 10 butter contains less fat trucks that run the than that produced by same route twice a competitor once with the current air filter installed and once with the new filter o 2002 The Wadsworth Group
Examples: Independent versus Dependent Samples • Independent Samples: – Testing a company’s claim that its peanut butter contains less fat than that produced by a competitor. • Dependent Samples: – Testing the relative fuel efficiency of 10 trucks that run the same route twice, once with the current air filter installed and once with the new filter. © 2002 The Wadsworth Group