The development of multivariate generalized autoregressive conditionally heteroscedastic (MGARCH) models from the original univariate specifications represented a major step forward in the modelling of time series. MGARCH models permit time-varying conditional covariances as well as variances,...

The emergence, from the 1960s on, of a new spatial division of labor – with the old task-based division of labor within a firm taking on a spatial dimension, and comparative advantage increasingly shaping patterns of specialization by function/process as well as by sector/product – reflected...