SOLVED

10) Distinguish a dependent variable from an independent variable. 11) Explain, in your own words, the meaning of the coefficient of determination. 12) A firm has modeled its experience with industrial accidents and found that the number of accidents per year (y-hat) is related to the number of employees (x) by the regression equation: y-hat = 3.3 + 0.049x. The r-squared value is 0.68. The regression is based on 20 annual observations. The firm intends to employ 480 workers next year. How many accidents do you project? How much confidence do you have in that forecast? 13) An innovative restaurateur owns and operates a dozen “Ultimate Low-Carb” restaurants in northern Arkansas. His signature item is a cheese-encrusted beef medallion wrapped in lettuce. Sales (x, in millions of dollars) is related to Profits (y-hat, in hundreds of thousands of dollars) by the regression equation y-hat = 8.21 + 0.76 x. What is your forecast of profit for a store with sales of $40 million? $50 million? 14) Arnold Tofu owns and operates a chain of 12 vegetable protein “hamburger” restaurants in northern Louisiana. Sales figures and profits for the stores are provided in the table below. Sales are given in millions of dollars; profits are in hundreds of thousands of dollars. Calculate a regression line for the data. What is your forecast of profit for a store with sales of $24 million? $30 million? Store Profits Sales 1 14 6 2 11 3 3 15 5 4 16 5 5 24 15 6 28 18 7 22 17 8 21 12 9 26 15 10 43 20 11 34 14 12 9 5