CHAPTER 10 Hypothesis Testing, One population Mean or proportion 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 10: Hypothesis Testing, One Population Mean or Proportion 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 10- Learning objectives Describe the logic of and transform verbal statements into null and alternative hypotheses Describe what is meant by Type I and Type II errors Conduct a hypothesis test for a single population mean or proportion Determine and explain the p-value of a test statistic Explain the relationship between confidence intervals and hypothesis tests o 2002 The Wadsworth Group
Chapter 10 - Learning Objectives • Describe the logic of and transform verbal statements into null and alternative hypotheses. • Describe what is meant by Type I and Type II errors. • Conduct a hypothesis test for a single population mean or proportion. • Determine and explain the p-value of a test statistic. • Explain the relationship between confidence intervals and hypothesis tests. © 2002 The Wadsworth Group
I Null and alternative hypotheses Null hypotheses Ho: Put here what is typical of the populatio a term that at characterizes business as usua/e where nothing out of the ordinary occurs Alternative Hypotheses H: Put here what is the challenge, the view of some characteristic of the population that, if it were true, would trigger some new action, some change in procedures that had previously defined business as usual o 2002 The Wadsworth Group
Null and Alternative Hypotheses • Null Hypotheses – H0 : Put here what is typical of the population, a term that characterizes “business as usual” where nothing out of the ordinary occurs. • Alternative Hypotheses – H1 : Put here what is the challenge, the view of some characteristic of the population that, if it were true, would trigger some new action, some change in procedures that had previously defined “business as usual.” © 2002 The Wadsworth Group
l Beginning an example When a robot welder is in adjustment, its mean time to perform its task is 1.3250 minutes. past experience has found the standard deviation of the cycle time to be 0. 0396 minutes. An incorrect mean operating time can disrupt the efficiency of other activities along the production line. For a recent random sample of 80 jobs the mean cycle time for the welder was 1.3229 minutes Does the machine appear to be in need of adjustment? o 2002 The Wadsworth Group
Beginning an Example • When a robot welder is in adjustment, its mean time to perform its task is 1.3250 minutes. Past experience has found the standard deviation of the cycle time to be 0.0396 minutes. An incorrect mean operating time can disrupt the efficiency of other activities along the production line. For a recent random sample of 80 jobs, the mean cycle time for the welder was 1.3229 minutes. Does the machine appear to be in need of adjustment? © 2002 The Wadsworth Group
l Building Hypotheses What decision is to be made? The robot welder is in adjustment The robot welder is not in adjustment How will we decide? In adjustment means u=1. 3250 minutes Not in adjustment means u* 1. 3250 minutes Which requires a change from business as usual? What triggers new action Not in adjustment-H1:μ≠1.3250 minutes o 2002 The Wadsworth Group
Building Hypotheses • What decision is to be made? – The robot welder is in adjustment. – The robot welder is not in adjustment. • How will we decide? – “In adjustment” means µ = 1.3250 minutes. – “Not in adjustment” means µ 1.3250 minutes. • Which requires a change from business as usual? What triggers new action? – Not in adjustment - H1 : µ 1.3250 minutes © 2002 The Wadsworth Group