years of full-time work experience
weeks worked
occupation; occ==1 if in a blue-collar occupation
industry; ind==1 if working in a manufacturing industry
residence; south==1 if in the South area
smsa==1 if in the Standard metropolitan statistical area
marital status
female or male
if wage set be a union contract
years of education
black
log wage
t==     1.0000
t==     2.0000
t==     3.0000
t==     4.0000
t==     5.0000
t==     6.0000
t==     7.0000