その 自己回帰的 Integrated 移動平均 (ARIMA) モデルは、分析に広く用いられる統計的手法です。 forecasting 時系列 data. It combines three key components: autoregression (AR), differencing (I), and moving average (MA).
その autoregressive part of the model indicates that the current value of the series is based on its past values. This is mathematically expressed as a 線形結合 of previous observations. The integrated component refers to the differencing of raw observations to allow for the time series to become stationary, meaning its statistical properties do not change over time. Finally, the 移動平均 component involves modeling the error term as a linear combination of previous error terms.
ARIMA is particularly useful for non-seasonal time series that exhibit patterns over time, making it an effective tool for forecasting in various fields such as finance, economics, and environmental studies. The model is denoted as ARIMA(p, d, q), where p represents the number of lag observations included in the model (the order of the autoregressive part), d is the degree of differencing (the number of times the data have had past values subtracted), and q は、移動平均ウィンドウのサイズです。
ARIMA models can be enhanced further by incorporating seasonal effects, in which case they are referred to as Seasonal ARIMA (SARIMA). The versatility and effectiveness of ARIMA in handling various time series data have made それを時系列予測の分野において重要な基盤としています。