Income Related to Years of School Completed

The United States Bureau of the Census collects data on highest level of education obtained and income. The table below lists data from 1997 where 12 years of school indicates a high school graduate, 16 years of school indicates a college graduate, 18 years of school indicates completion of a master's degree, 20 years of school indicates completion of a professional degree, and 22 years of school indicates completion of a doctoral degree.

Use a statistical package or a graphing calculator to make a scatterplot of this data set with the years of school as the independent variable and the income as the dependent variable. Then fit this data set with a least-squares line.

Interpret the R² value for this line.

Using your linear model, predict the income level of someone completing an associate degree. Also, predict the income level of someone who drops out of high school after the 9th grade. Discuss the reasonableness of this model.

Income levels relative to years of school