“…In these expansion formulas, six factors, including the own volatility11, 1 t h of the last period, the previous volatility 22, 1 t h of the opposing market, the covariance 12, 1 21, 1 , tt hh of the two different markets, the square of own former residual error the opposing market, and the interaction term of the two markets 1, 1 2, 1 tt…”