Different criteria exist to define long memory behavior. The two most used relate to the asymptotic decay of the autocovariance function of a process, and to the shape of its spectral density. In the case of a long memory process, the asymptotic decay of the autocovariance function is...

The aim of this paper is to identify permanent and transitory shocks. This identification is done according to the size of the shocks or the size of some other important economic variable. In order to be able to carry this identification scheme on, we introduce a new class of threshold models:...

There have been several instances over the past 40 years when large movements in the unemployment rate have elicited little response in the inflation rate. Such instances, while casting doubt on the tradeoff implied by the linear Phillips curve, are also associated with large inflation...