According to the U.S. Census Bureau, as of March 2009, the average earnings of full-time workers was estimated to be $31,666 for females with high school education, $43,493 for males with high school education, $60,293 for white females with a bachelor’s degree, and $94,206 for males with a bachelor’s degree.
a. Identify the response variable and the two factors.
b. Show these means in a two-way classification of the factors.
c. Compare the differences between males and females for
(i) High school graduates and
(ii) College graduates.
If these are close estimates of the population means, explain why there is interaction. Describe its nature.