Have an idea?

Visit Sawtooth Software Feedback to share your ideas on how we can improve our products.

Dual response none in chip allocation

Hi

I'm doing a survey, constant sum, basic setup and no none. After each question we ask each respondent each task to evaluate the total % of their purchases the previous sum would come to.

So first task, we have perhaps answers 50/50/0/0. Second question is ok, this 50/50 on your total volume, what would this amount to. eg 10%.

So now I want to recode the CHS file to include the nones as well.
so task 1
design concept1 50
design concept2 50
design concept3 0
design concept4 0

followed by the same task, but adding the none and having recalculated the 50 to the %
so task 1b
design concept1 5
design concept2 5
design concept3 0
design concept4 0
None design 90

I've changed the att file and checked the data and all look ok to me.
But every time I want to get the HB run through CBC/HB i get the popup saying the number of parameters and etc and then with the respondent statistics i see "index out of range".

Has anyone ever tried something like this, combining none tasks with tasks without none into 1 CHS file. If i put a none to every question, the file runs.

many thanks
asked Sep 23, 2016 by frederik

1 Answer

0 votes
Sorry, but at this time the CBC/HB data files do not allow respondents to have a mix of tasks with and without none options.

This can be achieved through user-specified codings.  It would involve coding all the attributes using effects coding, and then specifying that each column is a user-specified attribute within the interface.

Our support team can assist you if you need help in learning how to code the columns.
answered Sep 23, 2016 by Walter Williams Gold Sawtooth Software, Inc. (17,000 points)
Hi Walter,

tx for the answer.
Just to check, in an ACBC, you have the BYO being coded as task without none, screener as binary vs a none, tournemant as choicetasks wihtout none etc.. so this is a mix as well, and cbc/hb takes it up.

Is it because this is a CHS chip allocation and then it freezes.

many thanks for this
That is because the none is treated as a user-specified attribute instead of a none option.  You will notice in the header line for each respondent that the number denoting whether there is a none option is 0, which is the code to say the none is not present.
tx for the answer, I'll dig into the documentation on this and see if i can work it out
Another trick is to try thinking about formatting the tasks such that the None is a part of each task rather than one task having the None and the other task not having the None.
...