A description of Rodgers and Young (1981) data:

One hundred subjects rank-ordered 18 family types according to their preference. The data have been converted into "anti-preference" data by sutracting the original preference data from 19, and then centering within each subject (rowwise centering). The 18 family types are as follows:

1. No children
2. One boy
3. One girl
4. Two boys
5. Two girls
6. A boy then a girl
7. A girl then a boy
8. Three boys
9. Three girls
10. A boy then two girls
11. A girl then a boy then a girl
12. Two girls then a boy
13. A girl then two boys
14. A boy then a girl then a boy
15. Two boys then a girl
16. Four or more, equal boys and girls
17. Four or more, more boys than girls
18. Four or more, more girls than boys

Source: Rodgers, J. L., and Young, F. W. (1981). Successive unfolding of family preferences. Applied Psychological Measurement, 5, 51-62.


The right-hand side constraint matrix H is my own creation. There are 5 constraints, defined as follows:

1. Equal boys and girls, or not. (There are 4 cases in the former category, and 14 cases in the latter category, and a contrast vector was constructed to capture the difference between the two.)
2. More boys, or more girls. (Out of 14 cases with unequal numbers of boys and girls, 7 cases falls into the category of more boys, while 7 others into more gilrs. This contrast captures the difference between these two categories.)
3. The total number of children at most 2, or exactly 3. (There are 7 cases falling into the first category, while 8 cases into the second. This contrast takes the difference between these two categories.)
4. The total number of children at most 3, or larger than 3. (There are 15 cases falling into the first category, while 3 cases into the second. This contrast takes the difference between the these two categories.)
5. Children of one gender (only boys or only girls), or of mixed gender. (There are 9 cases falling into the former category, and 9 cases into the latter. This contrast takes the difference between the two categories.)