Dear authors,
thank you for building this nice package.
I would like to simulate a new choice within a logit model in Apollo. I would like to predict the aggregate market share of this new product and individual choice probabilities. I would like to do so it by altering the attributes of existing products and using the estimated parameters of the base model (with only the two original products). How can I do that? Essentially I would like to replicate example #6 from package mlogit in this link: https://cran.r-project.org/web/packages ... logit.html.
Thank you and best regards,
L
Important: Read this before posting to this forum
- This forum is for questions related to the use of Apollo. We will answer some general choice modelling questions too, where appropriate, and time permitting. We cannot answer questions about how to estimate choice models with other software packages.
- There is a very detailed manual for Apollo available at http://www.ApolloChoiceModelling.com/manual.html. This contains detailed descriptions of the various Apollo functions, and numerous examples are available at http://www.ApolloChoiceModelling.com/examples.html. In addition, help files are available for all functions, using e.g. ?apollo_mnl
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Simulation of new choice - market share of new product
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- Site Admin
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Re: Simulation of new choice - market share of new product
Hi
if this is just a case of changing the attribute levels for existing alternatives (rather than adding to the choice set), then this is discussed in detail in the manual and in the MNL_SP_covariates example on the apollo website - did you look at those?
Stephane
if this is just a case of changing the attribute levels for existing alternatives (rather than adding to the choice set), then this is discussed in detail in the manual and in the MNL_SP_covariates example on the apollo website - did you look at those?
Stephane
Re: Simulation of new choice - market share of new product
Hi Stephane,
thanks for the quick reply. Yes, I looked at those. As you say, to perturb the attributes those examples suffice. To add to the choice set I would need to think more carefully. I will come back if still needed.
Best
L
thanks for the quick reply. Yes, I looked at those. As you say, to perturb the attributes those examples suffice. To add to the choice set I would need to think more carefully. I will come back if still needed.
Best
L
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- Site Admin
- Posts: 1042
- Joined: 24 Apr 2020, 16:29
Re: Simulation of new choice - market share of new product
what you would need to do is to create a modified version of apollo_probabilities