Essentials of Statistics for Business and Economics, Loose-leaf Version
8th Edition
ISBN: 9781337114196
Author: David R. Anderson, Dennis J. Sweeney, Thomas A. Williams, Jeffrey D. Camm, James J. Cochran
Publisher: South-Western College Pub
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Textbook Question
Chapter 11.2, Problem 17E
Repair Costs as Automobiles Age. In its 2016 Auto Reliability Survey, Consumer Reports asked subscribers to report their maintenance and repair costs. Most individuals are aware of the fact that the average annual repair cost for an automobile depends on the age of the automobile. A researcher is interested in finding out whether the variance of the annual repair costs also increases with the age of the automobile. A sample of 26 automobiles 4 years old showed a sample standard deviation for annual repair costs of $170 and a sample of 25 automobiles 2 years old showed a sample standard deviation for annual repair costs of $100.
- a. State the null and alternative versions of the research hypothesis that the variance in annual repair costs is larger for the older automobiles.
- b. At a .01 level of significance, what is your conclusion? What is the p-value? Discuss the reasonableness of your findings.
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Chapter 11 Solutions
Essentials of Statistics for Business and Economics, Loose-leaf Version
Ch. 11.1 - 1. Find the following chi-square distribution...Ch. 11.1 - Prob. 2ECh. 11.1 - A sample of 16 items provides a sample standard...Ch. 11.1 - Prob. 4ECh. 11.1 - Prob. 5ECh. 11.1 - Prob. 6ECh. 11.1 - Volatility of General Electric Stock. To analyze...Ch. 11.1 - Variability in Daily Change in Stock Price....Ch. 11.1 - Prob. 9ECh. 11.1 - Costco Customer Satisfaction. Consumer Reports...
Ch. 11.1 - Prob. 11ECh. 11.1 - Vehicle Ownership by Fortune Magazine Subscribers....Ch. 11.2 - Find the following F distribution values from...Ch. 11.2 - A sample of 16 items from population 1 has a...Ch. 11.2 - Prob. 15ECh. 11.2 - Comparing Risk of Mutual Funds. Investors commonly...Ch. 11.2 - Repair Costs as Automobiles Age. In its 2016 Auto...Ch. 11.2 - Prob. 18ECh. 11.2 - Prob. 19ECh. 11.2 - Prob. 20ECh. 11.2 - 21. Many smartphones, especially those of the...Ch. 11.2 - Prob. 22ECh. 11 - 23. Because of staffing decisions, managers of the...Ch. 11 - Prob. 24SECh. 11 - Prob. 25SECh. 11 - Prob. 26SECh. 11 - Prob. 27SECh. 11 - Prob. 28SECh. 11 - Daily Patient Volume at Dental Clinic. A sample of...Ch. 11 - A sample standard deviation for the number of...Ch. 11 - Golf Scores. Is there any difference in the...Ch. 11 - Grade Point Average Comparison. The grade point...Ch. 11 - Prob. 33SECh. 11 - Two new assembly methods are tested and the...
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