Question

3.) Profits: Retail Jobs and productivity! How do retail stores rate? One way to answer this question is to examine annual profits per employee. The following data give annual profits per employee (in units of one thousand dollars per employee) for companies in retail sales. Assume ơ-38 thousand dollars. .4 6.5 4.2 8.9 8.7 866.0 11.9 8.2 6.4 4.7 5.5 483.0 4 1.7 9.4 5.5 5.8 476.2 2.6 2.9 8.11.9 3 -6.0 5 2.9 4.8 15.0 4.1 3.75 4.2 a.) Calculate the mean b.) Let us say that the preceding data are representative of the entire sector of retail sales companies. Find an 80% confidence interval for, the average annual profit per employee for retail sales. c.) Interpretation: Let us say that you are the manager of a retail store with a large number of employees. Suppose the annual profits per employee are less than 3 thousand dollars per employee. Do you think this might be low compared with other retail stores? Explain by referring to the confidence interval you computed in part b d.) Interpretation Suppose the annual profits are more than 6.5 thousand dollars per employee. As store manager, would you feel somewhat better? Explain by d.) Interpretation Suppose the annual profits are more than 6.5 thousand dollars per employee. As store manager, would you feel somewhat better? Explain by referring to the confidence interval from part b. e) Repeat parts (b), (c), and (d) for a 95% confidence interval

Answer 1

a Men - 35 ea η - 11 8.6 35 二 5, 103 $0.1. c1 = 3.8 x =5.103 3.8 Confidence limite - [Ftx * SE 5.039, s.167 @ yes, i think this mitht be low Compared witih othes netoil stoes becavse the annual Psofttper to 5-l67 thousand dollay Pey employee feel es, th's wovld the arge m neay to 6.5 thousand dollay Pey empoyee than (less than thousand clollay per emplby ee Someuwhat bettes, because

45% 7,L=1.96 S.E Confidence Limite [s. los干1.16 x 0.642] = [5.103干1.253 = [3345 , B.36) No, because 95% c.1 Syan ing fom 3.845 to 6.361