Prepare CBC Data Files (*.cho/*.chs & *.att)

CBC data are typically analyzed using Counts (within SMRT) and CBC/HB (hierarchical Bayes estimation). The data are exported from SSI Web into a .CHO or .CHS format (with accompanying .att labels file) in preparation for these analysis steps.

Once utilities are estimated, the results may be used within the Online Market Simulator, or within the simulator provided within the older SMRT platform. You received a copy of SMRT for analyzing CBC data with your purchase of CBC. The two files that CBC will automatically create for you for use in the SMRT software are:

STUDYNAME_EXERCISENAME.CHO file (text-only .CHO data file)

STUDYNAME_EXERCISENAME.ATT file (text-only text file of attribute level labels)

Prior to preparing the .CHO and .ATT files, you should have downloaded your data from the Web server to your study directory on your hard drive. Once you have downloaded the data, you are ready to export the CBC data to a .CHO/.CHS format file (with accompanying attribute labels in a file with extension .ATT), and estimate part-worths in preparation for running market simulations. Assuming you had downloaded the data as described above, you would click File | Data Management and then click Add Job.... Under Export Settings, you would name your export job something that reminds you what this export job does, and then you'd select the CBC file type. You would click OK to return to the Data Management dialog. You should select the new export job name, and then click Export all Checked Jobs.

The .CHO/.CHS and .ATT files can also be used within our Latent Class and Hierarchical Bayes estimation software modules for CBC. (Please see Appendix A for more information on interpreting conjoint analysis results.)

Question Types

This section lets you filter which types of choice tasks will be exported to the .CHO (or .CHS) file (Random, Fixed, or both). Most users will wish to export both types of choice tasks (Random and Fixed). All Sawtooth Software analytical systems for analyzing CBC results (SMRT, Latent Class, CBC/HB, HB-Sum) include a way to select which choice tasks will be used for utility estimation. Therefore, even if you include both Random and Fixed choice tasks in the .CHO file, you can set within the analytical software filters to selectively use the Random tasks for estimation.

Respondent Numbering

You can choose different ways for assigning respondent numbering. This lets you specify how the respondent numbers (case IDs) are to be generated. User Name is one of the passwords from the passwords module. You should only choose this if these values were purely numeric (no letters). Password is also one of the passwords from the passwords module. You should also only use this if the passwords were purely numeric (no letters). Internal Interview Numbers are those that the system assigns when respondents complete the survey over the Web. There can be gaps in the sequence if some respondents started a survey but didn't finish. Sequentially Assigned Numbers (default) are integers 1 through n. Other lets you choose another numeric variable to use for respondent numbering. This last option is useful if you are linking surveys from another source and need to merge the data sets by a "passed-in" variable.

Include

All Respondents

Choose this option to export all respondents: both complete and incomplete. Data for questions that were not completed are left blank.

Qualified/Completes Only

Choose this option to export only complete data records. A survey is considered qualified complete when respondents reach a terminating question that is marked with a qualified/complete status.

Disqualified and Incompletes Only

Choose this option to export only disqualified and incomplete data records. A survey is considered disqualified when respondents reach a terminating question that is marked with a disqualified status. A survey is considered incomplete if respondents have not reached a terminating question.