Residual-Based Fully Modified Vector Autoregression // Implements the Residual-Based Fully Modified Vector Autoregression (RBFM- VAR) estimator of Chang (2000) doi:10.1017/S0266466600166071. The RBFM-VAR procedure extends Phillips (1995) FM-VAR to handle any unknown mixture of I(0), I(1), and I(2) components without prior knowledge of the number or location of unit roots. Provides automatic lag selection via information criteria (AIC, BIC, HQ), long-run variance estimation using Bartlett, Parzen, or Quadratic Spectral kernels with Andrews (1991) doi:10.2307/2938229 automatic bandwidth selection, Granger non- causality testing with asymptotically chi-squared Wald statistics, impulse response functions (IRF) with bootstrap confidence intervals, forecast error variance decomposition (FEVD), and out-of-sample forecasting.