Seasonal Arima

Definition

\(ARIMA(p,d,q)\) model is a non-seasonal forecasting model

  • to incoroporate seasonality we need seasonal terms
    • whose order is indicated by capital letters \((P,D,Q)\)

Seasonal ARMA model data shows seasonal pattern every \(s\) observations

  • but after taking seasonal difference
    • the data behaves like ARMA model (stationary)

Seasonal ARIMA model data shows seasonal pattern every \(s\) observations

  • but after taking seasonal difference
    • the dat behaves like ARIMA model (non-stationary)