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Epa wants to determine if there is significant

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Unformatted text preview: Introduction to Business Statistics 70. A copy machine service company provides maintenance and repair service for different types and brands of copiers. The manager of the repair department wants to know if the repair time for brand A is higher than the repair time for brand B. The manager randomly selected 8 repair records associated with brand A and 8 repair records associated with brand B. The repair times for both samples in minutes are given below. The distribution of repair times for both brand A and brand B is highly skewed. What is the appropriate alternative hypothesis for this problem? A. HA: DA is shifted to the left or right of DB B. HA: DA is shifted to the right of DB C. C. HA: DA is shifted to the left of DB D. HA: DA is shifted equal to DB HA: DA is shifted to the right of DB or H0: µDA ≤ µ DB HA: DA is shifted to the right of DB or HA: µDA > µ DB AACSB: Reflective Thinking Bloom's: Comprehension Difficulty: Hard Learning Objective: 2 Topic: Rank Sum 1-1835 Chapter 01 - An Introduction to Business Statistics 71. A copy machine service company provides maintenance and repair service for different types and brands of copiers. The manager of the repair department wants to know if the repair time for brand A is higher than the repair time for brand B. The manager randomly selected 8 repair records associated with brand A and 8 repair records associated with brand B. The repair times for both samples in minutes are given below. The distribution of repair times for both brand A and brand B is highly skewed. On the average, can it be concluded that the repair time for brand A is significantly higher than the repair time for brand B? Test at α = .05. A. Reject the null hypothesis B. Fail to reject the null hypothesis Reject H0, it takes longer to repair brand A than to repair brand B. H0: DA and DB are identical probability distributions. or H0: µDA ≤ µ DB HA: DA is shifted to the right of DB or HA: µDA > µ DB T = 89.5 From table A15 for n1 = 8, and n2 = 8, TU = 84 Since 89.5 > 84, we reject H0 and conclude that the repair times for brand A is higher than the repair times for brand B. AACSB: Analytic Skills Bloom's: Application Difficulty: Hard Learning Objective: 2 Topic: Rank Sum 1-1836 Chapter 01 - An Introduction to Business Statistics 72. A cholesterol test was given to 10 heart patients with high cholesterol levels. The same 10 heart patients are then given a new cholesterol-reducing drug for six months. Before the patients begin taking the drug, they are told to maintain their current diets and eating habits so that the effect of the drug can be more effectively determined. After taking the drug for six months, the same patients are given a cholesterol test again. The pharmaceutical company that manufactures the drug wants to determine if the drug is helpful in reducing cholesterol levels. Distribution of cholesterol level is not normally distributed. State the alternative hypothesis for this problem. A. The probability distribution of cholesterol readings of patients before and after taking the drug for six months is identical. B. The probability distribution of cholesterol readings of patients before taking the drug has shifted to the right of the probability distribution of cholesterol readings of patients after taking the drug. C. The probability distribution of cholesterol readings of patients before taking the drug has shifted to the left of the probability distribution of cholesterol readings of patients after taking the drug. D. The probability distribution of cholesterol readings of patients before taking the drug has shifted to the right or left of the probability distribution of cholesterol readings of patients after taking the drug. AACSB: Reflective Thinking Bloom's: Knowledge Difficulty: Hard Learning Objective: 3 Topic: Signed rank test 1-1837 Chapter 01 - An Introduction to Business Statistics 73. A cholesterol test was given to 10 heart patients with high cholesterol levels. The same 10 heart patients are then given a new cholesterol-reducing drug for six months. Before the patients begin taking the drug, they are told to maintain their current diets and eating habits so that the effect of the drug can be more effectively determined. After taking the drug for six months, the same patients are given a cholesterol test again. The cholesterol levels before and after taking the drug is given below. Distribution of cholesterol level is not normally distributed. At α = .05, test to determine if the drug is helpful in reducing cholesterol levels. A. Reject the null hypothesis B. Fail to reject the null hypothesis 1-1838 Chapter 01 - An Introduction to Business Statistics Reject H0 H0: The probability distribution of cholesterol readings of patients before and after taking the drug for six months is identical. HA: The probability distribution of cholesterol readings of patients before taking the drug has shifted to the right of the probability distribution of chol...
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