TY JOUR TI THE USE OF MATRIX METHODS AND DUMMY VARIABLES FOR FORECASTING IN ECONOMETRIC MODELS KW econometrics KW linear regression KW least squares method KW matrix approach KW forecasting KW dummy variable KW Salkever method JO MOSCOW ECONOMIC JOURNAL AU Gorshunova, T.A. AU Bagautdinov, A.E. AU Mel'nikov, A.A. AU Stepanenko, A.I. PY 2026 IS 11 PB Electronic science