Work experience is generally found to be an important determinant of earnings.

If a direct measure is lacking in a data set, it is standard practice to use potential work experience, PWE, defined by PWE = AGE-S - 5 as a proxy. This is the maximum number of years since the completion of full-time education, assuming that an individual enters first grade at the age of six. Using your EAEF data set, first regress EARNINGS on Sand PWE, and then run the regression a second time adding AGE as well. Comment on the regression results.