Condition logit model for discrete choice model

[ELLA MA]

hi，

i have difficulty dealing with the conditional model for discrete choice model。
i have two scenes for people to choose. Every scenes have different characteristics.
and there also exist the “neither” option.
how to deal with the neither option in the data edit for conditional logit model.
thanks

best
ella

[Hong Il Yoo]

You can model "neither" as a third scene, the utility index of which is normalised to 0. This normalisation can be applied by setting all scene-specific characteristics to 0 for the "neither" option. You can also consider adding alternative-specific constant(s) to distinguish the two scene options from the "neither" option. See for example how Jose Oviedo and I distinguish the status quo from two reforestation projects in our paper (https://doi.org/10.1007/s10640-016-0058-7).