age. in years
black. =1 if black
case. identifier
clerical. =1 if clerical worker
construc. =1 if construction worker
educ. years of schooling
earns74. total earnings, 1974
gdhlth. =1 if in good or excel. health
inlf. =1 if in labor force
leis1. sleep - totwrk
leis2. slpnaps - totwrk
leis3. rlxall - totwrk
smsa. =1 if live in smsa
lhrwage. log hourly wage
lothinc. log othinc, unless othinc < 0
male. =1 if male
marr. =1 if married
prot. =1 if Protestant
rlxall. slpnaps + personal activs
selfe. =1 if self employed
sleep. mins sleep at night, per wk
slpnaps. minutes sleep, inc. naps
south. =1 if live in south
spsepay. spousal wage income
spwrk75. =1 if spouse works
totwrk. mins worked per week
union. =1 if belong to union
worknrm. mins work main job
workscnd. mins work second job
exper. age - educ - 6
yngkid. =1 if children < 3 present
yrsmarr. years married
hrwage. hourly wage
agesq. age^2