identifier
number of years in sample
81 to 87
sch=1,home=2,wc=3,bc=4,serv=5
annual wage, 1987 $
years of schooling
experience in white collar
experience in blue collar
experience in services
=1 if in manufacturing
=1 if black
log(wage)
=1 if year == 81
=1 if choice == 1
=1 if choice == 3, 4, or 5
=1 if attrit in next year
expwc + expbc + expser
exper^2
sch=1,home=2,work=3