A random sample of 30 companies on the Forbes 500 list was selected and the relationship between sales (in hundredsres thousands of dollars) and profits (in hundreds of thousands of dollars was investigated using regression. A least-squares regression line was fitted to the data using statistical software, with sales as the explanatory variable and profits as the response variable. Here is the output from the software: Dependent variable is Profits R-squared - 66.28 * = 466.2 with 30 - 2 = 28 degrees of freedom Variable Coefficient s. e. of Coefficient Constant -176.644 61.16 Sales 0.092498 0.0106 p-value 0.0050 50.0001 Which of the following is an appropriate interpretation of the number 0.092498? (a) For each increase of $100,000 in profits, the predicted sales increases by $9.249.80.
(b) For each increase of $100,000 in sales, the predicted profit increases by S9,249.80.
(c) Sales of $100,000 correspond to predicted average profits of $9,249.80.
(d) The actual profit typically varies by about $9249.80 from the profit predicted with the least squares regression line using x = sales.
(e) The actual sales typically varies by about $9249.80 from the sales predicted with the least squares regression line using x = profit.
2. Which of the following expressions best represents the margin of error of a 90% confidence interval for the slope of the population regression line?
(a) 1.701(0.0106)^1/2
(b) 1.645(0.0106/(38)^1/2)
(c) 1.701(0.0106)
(d) 1.645(0.0106)^1/2
(e) 1.701(0.0106/(38)^1/2)