Example of Two Indices for Variables to Cases
When a variable group records more than one factor, you can create more than one index; however, the current data must be arranged so that the levels of the first factor are a primary index within which the levels of subsequent factors cycle. In the current data, there is one variable group, width, and two factors, A and B. The data are arranged so that levels of factor B cycle within levels of factor A.
| subject | w_a1b1 | w_a1b2 | w_a2b1 | w_a2b2 |
|---|---|---|---|---|
| 1 | 5.5 | 6.4 | 5.8 | 5.9 |
| 2 | 7.4 | 7.1 | 5.6 | 6.7 |
We'll restructure the variable group into a single variable, width, and create two indices. The new data are shown in the following table.
| subject | index_a | index_b | width |
|---|---|---|---|
| 1 | 1 | 1 | 5.5 |
| 1 | 1 | 2 | 6.4 |
| 1 | 2 | 1 | 5.8 |
| 1 | 2 | 2 | 5.9 |
| 2 | 1 | 1 | 7.4 |
| 2 | 1 | 2 | 7.1 |
| 2 | 2 | 1 | 5.6 |
| 2 | 2 | 2 | 6.7 |