Before revision:  The approach exhibits clear forecasting gains over a wide range of alternativesand successfully predicts the drastic 2008  rise in unemployment .
After revision:  Its main output, Generalized Time-Varying Parameters (GTVPs), is a versatile device nesting many popular nonlinearities (threshold/switching, smooth transition, structural breaks/change) and allowing for sophisticated new ones. The approach delivers clear forecasting gains over a wide range of alternativesand successfully predicts the drastic 2008 rise in unemployment .