In a study of faculty salaries in a small college in the Midwest, a linear regression model was fit, giving the fitted mean function   where Sex equals 1 if the faculty member was female and 0 if...

In a study of faculty salaries in a small college in the Midwest, a linear regression model was fit, giving the fitted mean function

where Sex equals 1 if the faculty member was female and 0 if male. The response Salary is measured in dollars (the data are from the 1970s).