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Can I design a CVA survey with a number of questions pp that is lower than the SSiWeb minimum?

Now why would I want to do that?

I am designing a single concept CVA study. Each case has 7 attributes with 4 values per attribute. Per person, I only want to use 3 questions. The difference with a standard study is that I do not need or want to calculate individual utilities, which is why I can get away with 3 questions per person, but SSiWeb will not allow me to because it insists that the minimum number of questions per person is 22!

What I want is to in the end have a data set of the kind:

Id    Att1    Att2    ...    Att7    CVA_value
--------------------------------------------------
1    1    1    ...    2    8
1    1    2    ...    2    6
1    2    3    ...    1    5
--------------------------------------------------
2    2    2    ...    3    9
2    3    2    ...    1    6
2    1    4    ...    4    3
--------------------------------------------------
3    4    4    ...    2    5
3    3    1    ...    4    6
3    2    4    ...    3    1
...

where Id is a person Id, Att1-7 are the attribute values (which could be chosen at random, as far as I am concerned), and CVA_value is the answer to a question of which I have three per person.

Given such data, I then want to run my analyses (in Stata) myself, treating these as multi-level regression data. I am perfectly ok with that last bit, but because SSiWeb insists on a minimum value of 22 questions pp, I cannot get such a design implemented. Is there a workaround for this?
 
Thanks,
Chris
asked Mar 8, 2013 by anonymous
retagged Mar 8, 2013 by Walter Williams

1 Answer

0 votes
Please see our section in the CVA manual that discusses how to do "sparse" designs with negative degrees of freedom per respondent:

https://www.sawtoothsoftware.com/support/issues/ssiweb/online_help/index.html?negativedegreesoffreedomde.htm
answered Mar 8, 2013 by Bryan Orme Platinum Sawtooth Software, Inc. (154,305 points)
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