You are interested in estimating the effect of education on earnings using data on wages and education. Here, the wage is measured in dollars per hour. Thus, for a particular person, if wage = 6.75, the hourly wage is $6.75. Also, education denotes years of schooling; for example, education = 12 corresponds to a complete high school education. The data file wage4hw1.xlsx contains 526 individuals, who were randomly drawn from the population of people in the US workforce in 1976. The dataset has additional variables.

• exper: years of potential experience
• tenure: years with current employer
• prefocus: =1 if in a professional occupation
• cleric: =1 if in clerical occupation
• service: =1 if in a service occupation