why would you consider the time series a new model when should a model be changed when to use the arimax model how to maintain the coefficient in the arima model what's the difference between a time series and an updated model? when do you change the coefficients of an average time series model what is new modeling vs an older model when to use new model vs new time series can you use arimax time series why is it necessary to update a time series model should the coefficients in a time series be changed when a model has been developed? why do we update time series models how do i use an aima model what is natural compared to an updated model how to forecast from an arimax time series what is natural time series what is natural time series how to forecast arimax how to do an arimax when is it normal to create a time series