What problem does it solve?
This Skill solves the problem of turning raw time series into reliable forecasts by identifying models, fitting them correctly, decomposing seasonality, and comparing predictive accuracy with rigorous metrics.
Core Features & Use Cases
- Univariate ARIMA/SARIMA modeling: Use stationarity testing plus ACF/PACF-driven identification to fit ARIMA and generate forecasts.
- Seasonality decomposition: Apply STL to separate trend and seasonal components for clearer interpretation and better modeling.
- Multivariate dynamics with VAR: Model interactions across multiple correlated time series and analyze effects via Granger causality and impulse response functions.
- Volatility modeling with GARCH: Capture time-varying variance (volatility clustering) with GARCH(1,1) and produce conditional volatility forecasts.
- Forecast evaluation and comparison: Compute scale-free errors (e.g., MASE) and use Diebold-Mariano testing to compare competing forecasts.
Quick Start
Use the time-series-analysis skill to run stationarity checks, fit ARIMA/SARIMA, perform STL decomposition, and evaluate a 24-step forecast with MASE and (optionally) the Diebold-Mariano test.