Question: Earnings and gender the data in the table show the 2007 average earnings of year-round full-time workers by gender for several different levels of educational attainment.
(a) Use linear regression to find the linear equation that is the best for these data, with x representing the earnings for males and y representing the earnings for females.
(b) Find and interpret the slope of the linear regression line.
(c) If you made a similar linear model with data from 1965, how do you think its slope would compare with the slope found in part (b)? Explain.