I have a file of survey responses from a Choice-Based Conjoint (CBC) questionnaire. Each scenario was built from a combination of attributes and levels, with known efficiency, to make the choice sets.
The design assumed that interactions among the attributes were insignificant in two-way (and higher) interactions.
20 groups of survey questions were created (called blocking) so respondents did not have answer a ton of questions.
Respondents were asked to choose between two choices, A and B. The driver# = the respondent.
A sample of the data is shown here:
...
The driver# = the respondent. When I run asclogit:
asclogit SP_choice distance TT max_TT toll if LorS==1, case(choiceset) alternatives(alternative) casevars(work_type yrs_truck)
I get results that thinks each choiceset is independent of each other when, in fact, it is not. It should also take into consideration the driver#. Can anyone tell me how to group appropriately? Thanks so much!
Sue
The design assumed that interactions among the attributes were insignificant in two-way (and higher) interactions.
20 groups of survey questions were created (called blocking) so respondents did not have answer a ton of questions.
Respondents were asked to choose between two choices, A and B. The driver# = the respondent.
A sample of the data is shown here:
| line | choiceset | SP_scenario | driver# | SP_Q# | LorS | alternative | distance | TT | max_TT | toll | SP_choice | work_type | yrs_truck |
| 1 | 1 | 1 | 1 | 18 | 1 | A | 55 | 83 | 122 | -4 | 1 | 1 | 14 |
| 2 | 1 | 1 | 1 | 18 | 1 | B | 65 | 105 | 142 | 8 | 0 | 1 | 14 |
| 3 | 2 | 1 | 1 | 19 | 1 | A | 65 | 83 | 142 | 0 | 0 | 1 | 14 |
| 4 | 2 | 1 | 1 | 19 | 1 | B | 60 | 92 | 133 | -8 | 1 | 1 | 14 |
The driver# = the respondent. When I run asclogit:
asclogit SP_choice distance TT max_TT toll if LorS==1, case(choiceset) alternatives(alternative) casevars(work_type yrs_truck)
I get results that thinks each choiceset is independent of each other when, in fact, it is not. It should also take into consideration the driver#. Can anyone tell me how to group appropriately? Thanks so much!
Sue
