0 = male
1 = female

1 = students
2 = workers
3 = salesman
4 = marketing staff
5 = customer service staff
6 = support staff
7 = human resource staff
8 = financial staff
9 = assistant or office staff
10 = research staff
11 = administrative staff
12 = teacher
13 = consultant
14 = professionals
15 = others

Have you taken any courses in finance or economics?
1 = 是
2 = 否

whether the SS zero were explict
0 = absent
1 = present

1 = Hidden zero
2 = SS zero
3 = LL zero
4 = Explicit zero