Model order — ARIMA(p,d,q)

Data generation

Forecast

Stationarity check

Var(original y)—
Var(d-differenced)—
Variance ratio—
ADF t-stat (raw y)—
ADF t-stat (differenced)—
—

Fitted coefficients

φ: —
θ: —
Residual σ²—
AIC (approx.)—
Coefficients are estimated live from the generated data: the AR part via Yule-Walker/Levinson-Durbin on the differenced series, then AR+MA jointly refined with the Hannan-Rissanen conditional-least-squares method. Nothing here is hand-tuned — change p, d or q and the numbers above recompute from scratch.