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 $180 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. Let 4 year old automobiles be represented by population 1. Ho : of less than or equal to H, : o greater than b. At a 0.01 level of significance, what is your conclusion? Calculate the value of the test statistic (to 2 decimals). The p-value is less than 0.01 O. Use Table 4 of Appendix B. Conclude that 4 year old automobiles have a larger variance in annual repair costs compared to 2 year old automobiles.

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 $180 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. Let 4 year old automobiles be represented by population 1. Ho : of less than or equal to H, : o greater than b. At a 0.01 level of significance, what is your conclusion? Calculate the value of the test statistic (to 2 decimals). The p-value is less than 0.01 O. Use Table 4 of Appendix B. Conclude that 4 year old automobiles have a larger variance in annual repair costs compared to 2 year old automobiles.

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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