There are only two ways that ACBC automatically supports the "None" option:
1. A "None" utility automatically results from a standard ACBC interview, where the None alternative is the "Not a possibility" option from the "Consideration Phase" section of the survey.
2. If you add the optional "Calibration" section at the end of the ACBC survey (the 1-5 purchase intent scale), then you can ask the software to estimate a new None utility that corresponds to a researcher-specified point on the purchase intent scale. For example, if you think that a 4 on a 5-point scale indicates the purchase/not purchase threshold, then the software will estimate a None utility that best fits a 4 on the 5-point scale with respect to the profile's utility.
