library(stargazer)

data<-read.table("http://kanggc.iptime.org/book/data/income.txt", header=T)

age<-data$age
ed<- data$ed
gender<-data$gender
income<-data$income

age;ed;gender;income

high<-ifelse(data$ed==3, 1, 0)
college<-ifelse(data$ed>3, 1, 0)

(cbind(income,age,gender, ed,high,college))

m1.lm<-lm(income~age+gender+high+college)
summary(m1.lm)

stargazer(m1.lm, type="text", title="Regression Results of using Dummy Variable")