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Arima

  • for data shows clear trends or seasonal patterns

  • ideal for short-term forecasts

  • can use differencing to remove non-stationary trend

SARIMAX example

https://github.com/SamWachira/Electricity-Demand-Forecasting/blob/main/Time_Series_Electricity.ipynb

ARIMAX (autoregressive integrated moving average with exogenous variables)

  • The ARIMAX model is an extension of the standard ARIMA model, and

  • it allows for the inclusion of one or more exogenous variables in the model equation.

  • The ARIMAX model can be estimated using maximum likelihood estimation, and

  • the parameters of the model can be estimated using numerical optimization techniques.

components

  • Auto-Regressive (AR):
  • determine the present value based on historical values
  • only for data with stationary trend

  • Moving Average (MA):

  • smoothen variations to reveal the underlying trend
  • only for data with stationary trend

  • Integrated (I):

  • integrate the AR and MA elements by computing differences between current and past values
  • transform the dataset into a stationary trend

parameters

  • p: the number of past values considered for the AR component

  • q: the number of moving averages applied

  • d: the number of past values subject to differentiation

limit

lacking adaptability