Manually set model parameters in SARIMAX for prediction

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Sarem Seitz

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May 13, 2018, 7:29:00 AM5/13/18
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Hi,

using some articles form Chad Fulton's site as a guidance, I have estimated the model parameters for
a SARIMAX model. Now I want to get the posterior predictive forecasts for out-of-sample dates of my time series.
I have tried so by fitting another SARIMAX model of the same type via MLE and then manually adjusted
the model.params from the posterior predictive distributions of the estimated parameters.
However, the .predict() method does not seem to use the model.params for prediction but the relevant values
seem to be stored somewhere else, as the predictions are always the same for each draw from the posterior.

My question: Where are the parameters stored that are actually being used for SARIMXfit.predict()? Or
is there another intended way to perform predictions with a given set of model parameters?

Thanks for any help,
Sarem

josef...@gmail.com

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May 13, 2018, 8:12:44 AM5/13/18
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All the statespace model need to create the underlying statespace representation (kalman filter) to make prediction.

see Chad's answer for how estimated params can be used with a new dataset, and the issues for the explanation


Josef
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