Sawtooth Software Conference 2019 | San Diego, CA, USA | September 23–27

Constructing Parent and Child Lists

Below are two questions from an SSI Web survey. How do I create a constructed list to build the drop-down boxes for these questions?

Q1. At what price is this product starting to get expensive but you would still consider buying it? (INSERT DROP DOWN MENU OF PRICES RANGING FROM \$5,000 TO \$2,500 AT \$100 INCREMENTS. INCLUDE "LESS THAN \$2,500".)

Q2. At what price is this product too expensive that you wouldn't consider buying it? (INCLUDE DROP DOWN MENU OF PRICES FROM Q1 WITH ALL PRICES HIGHER THAN ANSWER AT Q1. INCLUDE "MORE THAN \$5,000".)

First, you need to create a master predefined list with all of the items on it. Let's call it masterList. It will contain the following items:

1. MORE THAN \$5,000
2. \$5,000
3. \$4,900
4. \$4,800
5. \$4,700
6. \$4,600
7. \$4,500
8. \$4,400
9. \$4,300
10. \$4,200
11. \$4,100
12. \$4,000
13. \$3,900
14. \$3,800
15. \$3,700
16. \$3,600
17. \$3,500
18. \$3,400
19. \$3,300
20. \$3,200
21. \$3,100
22. \$3,000
23. \$2,900
24. \$2,800
25. \$2,700
26. \$2,600
27. \$2,500
28. LESS THAN \$2,500

Next, we need to add the Q1 question. Create a select/dropdown question that uses a new constructed list. Call the list Q1List. It is based on the parent list of masterList. The list-building syntax you would use is:

`ADD (masterList, 2, 28)`

This simply adds items 2 through 28 to the list. If you were to take the survey and answer this question by selecting \$4,000, the value of 12 would be stored in Q1.

Finally, create the Q2 question. This will be another select/dropdown question that uses a new constructed list. Call the list Q2List. It is also based on the parent list masterList. The list-building logic you need to use is:

```ADD (masterList)
LISTMAX (Q1-1)```

The first line adds all of the items from masterList. The second line limits the size of that list to whatever the value that was selected in Q1, minus 1. In this case, if you selected \$4,000 in Q1, the value of Q1 would be 12, subtracting 1 makes it 11, which means that the list will start at item #1 and end with item #11, or \$4,100.

Below is a working example of this survey: