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No-choice option

Ask questions about model specifications. Ideally include a mathematical explanation of your proposed model.
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marah
Posts: 15
Joined: 13 Jan 2022, 03:06

No-choice option

Post by marah »

Hi Stephane,

I am estimating models for a standard DCE that includes an opt-out option. I have looked at the other discussions on this forum about similar topics but am still unsure how to set up my dataset to include an opt-out option. There are 3 alternatives in each choice set and an opt-out. I have three variables, let's call them pu, meb, and sc. I have therefore created variables pu1, pu2, pu3, meb1, meb2, meb3, sc1, sc2, sc3 in my dataset. So, I have accounted for the three alternatives. But what do I do about the opt-out option?

Thanks,

Mara
stephanehess
Site Admin
Posts: 974
Joined: 24 Apr 2020, 16:29

Re: No-choice option

Post by stephanehess »

Mara

if your opt-out has attributes, then they need to be included in the data. If the opt-out does not have attributes, then nothing is needed in the data and you can just estimate a constant for the opt-out

Stephane
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Stephane Hess
www.stephanehess.me.uk
marah
Posts: 15
Joined: 13 Jan 2022, 03:06

Re: No-choice option

Post by marah »

Thanks Stephane. How do I code the “choice” variable (which specifies the option the respondent chooses in each choice set) when a respondent chooses the opt-out option? With three alternatives, do I code it as 4? Or some other way?
stephanehess
Site Admin
Posts: 974
Joined: 24 Apr 2020, 16:29

Re: No-choice option

Post by stephanehess »

Mara

however you want. You will have a column in your data with the choice variable. Whatever number you use there for the no choice needs to then be used also in the Apollo code.

Stephane
--------------------------------
Stephane Hess
www.stephanehess.me.uk
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