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Prediction with alternate dataset

Ask questions about post-estimation functions (e.g. prediction, conditionals, etc) or other processing of results.
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mattwigway
Posts: 1
Joined: 08 Aug 2022, 17:36

Prediction with alternate dataset

Post by mattwigway » 08 Aug 2022, 17:58

Is it possible to use an estimated model object to predict for a new dataset (with the same schema)? In travel demand modeling we often will estimate a model using a survey dataset and then use the model to make predictions for a synthetic population. I don't see a way to specify a separate dataset in apollo_probabilities, and apollo_outOfSample seems to be only be used for cross-validation/train-test validation where a single dataset is split, not where there are separate datasets. Does Apollo have this functionality in another function I'm not aware of?

stephanehess
Site Admin
Posts: 672
Joined: 24 Apr 2020, 16:29

Re: Prediction with alternate dataset

Post by stephanehess » 09 Aug 2022, 16:31

Hi

yes, this is straightforward.

Let's say that after model estimation, you want to use a new database called data_for_prediction.

you would then use these steps:

Code: Select all

database = data_for_prediction
apollo_inputs = apollo_validateInputs()
pred=apollo_prediction(model,apollo_probabilities,apollo_inputs)
The important step is the replacement of database by a new one, and then the call to apollo_validateInputs()

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

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