We develop a numerical procedure that facilitates efficient likelihood evaluation in applications involving non-linear and non-Gaussian state-space models. The procedure employs continuous approximations of filtering densities, and delivers unconditionally optimal global approximations of...

We use population data from the U.S. Census to track regional patterns of growth from 1790 through 1990. At the county level, we find that an initial general tendency towards population convergence lasting roughly through the 1800s becomes dramatically reversed: particularly in the post-WWII...

We develop a forecasting model of GDP growth that features regime-switching behavior and an error-correction mechanism (ECM). Regime changes are manifested in the behavior of a stochastic regime drift component that moves between expansionary and contractionary phases, thus generating cycles in...