I have a CBC project (dual response none with only 2 scenarios per task to choose from) with one fixed task. This task had several aims:

1- Differentiate logical respondents from illogical as the choice is obvious

2- test how many respondents will prefer the scenario over the none response

My question is:

1- Is it appropriate to include or exclude this task when generating the model (logit-LC-HB) for the project? I understand that exclusion is more appropriate but I am not clear on the reason.

2- Is the item reported (none) in the results corresponds to the utility of the (dual response none option) and I can use it as an anchor for all the other utilities?

3- if 2 is true and I want this anchor to be =0, will it be appropriate to subtract the utility value from all the other utilities or how can I go about this?

Regards'

My none option is (death), and the other 2 scenarios are 2 different health states described using 6 attributed (we call them dimensions & each having 5 or 6 different levels). The first step is to choose which one of the 2 health states is better; then, the second step is to compare the worse state with death. It is kind of similar to BWS CBC but in a sequential manner and still a CBC task.

I want the final utilities of each of the levels in the attributes to be directly anchored to death and death to be equal to 0 so that I can rescale the utilities of all the possible health states on a 0-1 scale were 0 is death & 1 is full health (health states are allowed to be with a negative value).

This is my optimal aim and why I am performing this anchoring/rescaling process.