9. The Taylor Steel Company wants to determine whether there is a significant difference inproductivity between day-shift workers and night-shift workers. A random sample of 130 day-shiftworkers shows a mean output of 66.3 parts per hour with a standard deviation of 14.0 parts perhour, while a random sample of 120 night-shift workers shows a mean output of 62.7 parts perhour with a standard deviation of 16.0 parts per hour.a. Is there evidence in these results of a difference in productivity between day-shift and night-shift workers? Use a 5% significance level. (Do not assume that the two populationstandard deviations are equal. Show all four steps of your hypothesis test.)b. Calculate a 95% confidence interval for the difference between the group means. Whatdoes this confidence interval imply about whether you can reject the null hypothesis of nodifference in productivity between the two shifts? Is this result consistent with the resultsof your t-test of the difference in means in part a? Explain why it is (or isn’t).

Solution: Given information: n1= 130 Sample size of day shiftn2= 120 Sample size of night shiftx1=…

Answered: 9. The Taylor Steel Company wants to…

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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