*
* Example 8.1 on page 260
*
open data wage1.raw
data(format=free,org=columns) 1 526 wage educ exper tenure nonwhite female married numdep smsa northcen $
  south west construc ndurman trcommpu trade services profserv profocc clerocc servocc lwage expersq tenursq
*
* These show how to create the squared series
*
set expersq = exper**2
set tenursq = tenure**2
*
* And these are the interactive dummies
*
set marrmale = married*(1-female)
set marrfem  = married*female
set singfem  = (1-married)*female
set singmale = (1-married)*(1-female)
*
linreg lwage
# constant marrmale marrfem singfem educ exper expersq tenure tenursq
*
* OLS with heteroskedasticity-robust standard errors
*
linreg(robust) lwage
# constant marrmale marrfem singfem educ exper expersq tenure tenursq