In this article we model the log of the U.S. and the U.K. real oil prices in terms of fractionally integrated processes with a mean shift. We use different versions of the tests of Robinson (1994), which have standard null and local limit distributions. The results indicate that if we model the...

Since the 1960s hydrocarbons like crude oil and natural gas have been the most important energy source to fuel the world economy. Despite high recent growth rates for renewable energies, hydro- carbons are expected to be a dominant source of energy for several decades to come. In the last 20...

This article is concerned with the dynamic behaviour of UK unemployment. However, instead of using traditional approaches based on I(0) stationary or I(1) (integrated and/or cointegrated) models, we use the fractional integration framework. In doing so, we allow for a more careful study of the...