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SYNTAX ISSUE - The 'model$estimates' object should be a named vector for models not estimated using HB!

Ask questions about errors you encouunter. Please make sure to include full details about your model specifications, and ideally your model file.
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jdevalck
Posts: 1
Joined: 24 Nov 2024, 23:44

SYNTAX ISSUE - The 'model$estimates' object should be a named vector for models not estimated using HB!

Post by jdevalck »

Hi,

I'm new to using Apollo (recently converted from Stata) and probably not doing the right thing here.
I'm trying to split my data sample into 2 groups based on one dummy variable, get two mixed MNL models with similar configurations and test the model coefficients for significant differences.
Reading the manual, I'm trying to do this using two components, replacing the original RP/SP split with my two groups.
Model seems to run fine, although I am not shown the two model results.
So, I'm now adding the "Model Predictions and Elasticity Calculations" part.
Trying to set up my base in predictions_base using the following expression:

### Use the estimated model to make predictions
predictions_base = apollo_prediction(model,
apollo_probabilities,
apollo_inputs,
prediction_settings=list(modelComponent = "REG"))

### Look at a summary of the predicted choice probabilities
summary(predictions_base)

I get the error message:
Error in apollo_prediction(model, apollo_probabilities, apollo_inputs, :
SYNTAX ISSUE - The 'model$estimates' object should be a named vector for models not estimated using HB!

Am I missing something critical here?

Thank you very much for your help. Cheers, Jeremy
stephanehess
Site Admin
Posts: 1365
Joined: 24 Apr 2020, 16:29

Re: SYNTAX ISSUE - The 'model$estimates' object should be a named vector for models not estimated using HB!

Post by stephanehess »

Hi

difficult to help without seeing your code, but note that apollo_prediction is for prediction. You want apollo_modelOutput

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