ApolloChoiceModelling forum

Hi Stephane, and apologies for the delayed reply.

Following your advice, I simplified the model: now only the ASCs and the (generic) price coefficient are specified as random, while the coefficients for the modifiers (variants) are fixed. The model is still estimated in WTP space and now it is ...

Dear Moderators,

I am working to estimate a mixed logit model in the willingness-to-pay (WTP) space using stated preference data. My objective is to estimate brand-specific WTP for consumer goods while evaluating the conditional parameters of the model.

My dataset covers two product categories ...

Hello, Stephane.

1- Yes, the bug (the date warning) was resolved and it is not showing up anymore.

2- Yes, I am still with the other issue. Would you have any directions on that?


Thank you very much.

Rafael

Hello, Stephane.

Thank you for your reply.

It should be the last version (v0.2.9). Strangely, however, even after updating (or removing apollo and installing again), I am receiving a message that my version is more than six months old.

Rafael.



library(apollo)

Apollo 0.2.9
http://www ...

Dear Professor,

I am getting the following error when I add one or more random parameters to a HB model. It happens with different number of random parameters (ex., "asc_tresc" only, "b_cost" only, all parameters except "asc_outro" etc.) or type of distributions (ex., N, CN+, LN-, etc.).

Error in ...

Hello, Professor.

I would like to run a mediation analysis with a latent variable as a mediator. Consider, for example, the following model:

Independent variable (X): treatment variable in which subjects receive or not a benefit;
Mediator (M): a latent variable (ex., car lover) using ordered ...

Hi Stephane,

I am sorry, but I have averaged across draws as you mentioned and then fixed the database.

However, the error persistis. I have just updated R, R Studio, and Apollo to make sure that it is not a update issue.

Again, follow the code and the (fixed) database: https://1drv.ms/u/s ...

Dear Professor,

Follow the database (link) and script below.

(I think, the first message has not attached the files.)

Thank you again.

Best, Rafael.



DATABASE:
drive.google.com/file/d/1VXJSN7LI82thnclt7Gx2JFvI8FRhxyxX/view?usp=sharing

SCRIPT ...

Dear Professors,

I am trying to fit a RP/SP model with random parameters.

However, I am getting the following error:
Error in apollo_mnl(mnl_settings = mnl_settings_SP, functionality) :
Duplicated componentName found (MNL). Names must be different for each component.

Any suggestions are highly ...

Dear Professors,

I am trying to model a choice behavior in which buyers choose among alternatives "sequentially", i.e., there is a state dependence issue. It is a medicine choice context, where persons choose combos of three brands for a sequential application. For example, one person can choose ...