Applied Statistics in Business and Economics
5th Edition
ISBN: 9780077837303
Author: David Doane, Lori Seward Senior Instructor of Operations Management
Publisher: McGraw-Hill Education
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Textbook Question
Chapter 10, Problem 69CE
A ski company in Vail owns two ski shops, one on the west side and one on the east side of Vail. Is there a difference in daily average goggle sales between the two stores? Assume equal variances. (a) State the hypotheses for a two-tailed test. (b) State the decision rule for a level of significance equal to 5 percent and sketch it. (c) Find the test statistic and state your conclusion.
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Chapter 10 Solutions
Applied Statistics in Business and Economics
Ch. 10.2 - Do a two-sample test for equality of means...Ch. 10.2 - Repeat the previous exercise, assuming unequal...Ch. 10.2 - Is there a difference in the average number of...Ch. 10.2 - Prob. 4SECh. 10.2 - Prob. 5SECh. 10.2 - Prob. 6SECh. 10.2 - Prob. 7SECh. 10.2 - On a random basis, Bob buys a small take-out...Ch. 10.2 - For a marketing class term project, Bob is...Ch. 10.3 - A special bumper was installed on selected...
Ch. 10.3 - In trials of an experimental internet-based method...Ch. 10.3 - Construct a 95 percent confidence interval for the...Ch. 10.4 - (a) At = .05, does the following sample show that...Ch. 10.4 - An experimental surgical procedure is being...Ch. 10.4 - Blue Box is testing a new half price on Tuesday...Ch. 10.4 - The U.S. governments Cash for Clunkers program...Ch. 10.4 - Prob. 17SECh. 10.4 - Below is a random sample of shoe sizes for 12...Ch. 10.4 - A newly installed automatic gate system was being...Ch. 10.5 - Calculate the test statistic and p-value for a...Ch. 10.5 - Prob. 21SECh. 10.5 - Prob. 22SECh. 10.5 - Prob. 23SECh. 10.5 - Prob. 24SECh. 10.5 - Prob. 25SECh. 10.5 - A survey of 100 mayonnaise purchasers showed that...Ch. 10.5 - Prob. 27SECh. 10.5 - Prob. 28SECh. 10.5 - When tested for compliance with Sarbanes-Oxley...Ch. 10.5 - In 2009, a sample of 200 in-store shoppers showed...Ch. 10.5 - From a telephone log, an executive finds that 36...Ch. 10.5 - Prob. 32SECh. 10.6 - The American Bankers Association reported that, in...Ch. 10.6 - A study showed that 36 of 72 cell phone users with...Ch. 10.6 - Prob. 35SECh. 10.7 - Which samples show unequal variances? Use = .10...Ch. 10.7 - Prob. 37SECh. 10.7 - Prob. 38SECh. 10.7 - A manufacturing process drills holes in sheet...Ch. 10.7 - Examine the data below showing the weights (in...Ch. 10 - (a) Explain why two samples from the same...Ch. 10 - (a) In a two-sample test of proportions, what is a...Ch. 10 - List the three cases for a test comparing two...Ch. 10 - Consider Case 1 (known variances) in the test...Ch. 10 - Consider Case 2 (unknown but equal variances) in...Ch. 10 - Consider Case 3 (unknown and unequal variances) in...Ch. 10 - Why is it a good idea to use a computer program...Ch. 10 - (a) Explain why the paired t test for dependent...Ch. 10 - Explain how a difference in means could be...Ch. 10 - (a) Why do we use an F test? (b) When two...Ch. 10 - (a) In an F test for two variances, explain how to...Ch. 10 - Prob. 41CECh. 10 - In an early home game, an NBA team made 66 of...Ch. 10 - Prob. 43CECh. 10 - A recent study found that 202 women held board...Ch. 10 - A study of the Fortune 100 board of director...Ch. 10 - Prob. 46CECh. 10 - How many full-page advertisements are found in a...Ch. 10 - eShopNet, an online clothing retailer, is testing...Ch. 10 - After John F. Kennedy Jr. was killed in an...Ch. 10 - A ski company in Vail owns two ski shops, one on...Ch. 10 - At a University of Colorado womens home basketball...Ch. 10 - A ski resort tracks the proportion of seasonal...Ch. 10 - Does a follow-up reminder increase the renewal...Ch. 10 - A study revealed that the 30-day readmission rate...Ch. 10 - In a marketing class, 44 student members of...Ch. 10 - In San Francisco, a sample of 3,200 wireless...Ch. 10 - Prob. 57CECh. 10 - Prob. 58CECh. 10 - Prob. 59CECh. 10 - Prob. 60CECh. 10 - Prob. 61CECh. 10 - Prob. 62CECh. 10 - In a 15-day survey of air pollution in two...Ch. 10 - Prob. 64CECh. 10 - Do male and female school superintendents earn the...Ch. 10 - The average take-out order size for Ashoka Curry...Ch. 10 - Cash withdrawals from a college credit union for a...Ch. 10 - In Mini Case 10.2, we found that the mean methane...Ch. 10 - A ski company in Vail owns two ski shops, one on...Ch. 10 - A ski company in Vail owns two ski shops, one on...Ch. 10 - Emergency room arrivals in a large hospital showed...Ch. 10 - Concerned about graffiti, mayors of nine suburban...Ch. 10 - A certain company will purchase the house of any...Ch. 10 - Nine homes are chosen at random from real estate...Ch. 10 - Prob. 75CECh. 10 - Prob. 76CECh. 10 - Prob. 77CECh. 10 - Is there a difference between the variance in ages...Ch. 10 - A survey of 100 mayonnaise purchasers showed that...Ch. 10 - A 20-minute consumer survey mailed to 500 adults...Ch. 10 - One group of accounting students used simulation...Ch. 10 - Advertisers fear that users of DVRs (digital video...Ch. 10 - In preliminary tests of a vaccine that may help...Ch. 10 - Prob. 84CECh. 10 - Male and female students in a finance class were...Ch. 10 - Prob. 86CECh. 10 - A retailer compared the frequency of customer...Ch. 10 - Streeling University surveyed a random sample of...Ch. 10 - The Fischer Theatre compared attendance at its...Ch. 10 - Random samples of tires being replaced by a car...Ch. 10 - Count the number of two-door vehicles among 50...Ch. 10 - Which statement is not correct? Explain. a. The...Ch. 10 - Match each statement to the correct property of an...Ch. 10 - Concerning confidence intervals, which statement...Ch. 10 - Prob. 4ERQCh. 10 - Prob. 5ERQCh. 10 - Prob. 6ERQCh. 10 - Prob. 7ERQCh. 10 - Prob. 8ERQCh. 10 - The process that produces Sonora Bars (a type of...Ch. 10 - Prob. 10ERQCh. 10 - Prob. 11ERQCh. 10 - Last month, 85 percent of the visitors to the...Ch. 10 - Weights of 12 randomly chosen Sonora Bars (a type...Ch. 10 - In a random sample of 200 Colorado residents, 150...Ch. 10 - Five students in a large lecture class compared...Ch. 10 - Prob. 16ERQCh. 10 - Prob. 17ERQ
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