python - Machine learning mode retraining after getting new data - Data Science Stack Exchange


i have trained model predicting sale of items daily, such daily car sales, machine learning model in python. new time real data (time series data). want retrain mode. there issues:

  1. how data should use retraining model, namely what's time range of data or when should retrain model. example use new 1 day or 1 week et al., data retrain model.

  2. what's condition of new data if want use new data retraining model.

  3. how evaluate stability of new training model, , how know abnormal prediction new model.

once trained model, have measure of accuracy.

you should retrain model when accuracy drops below threshold.

another approach use bayesian model, in update model each new observation.

i suggest looking pymc3's examples


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