This paper analyzes the impact of commodity price shocks and global supply chain disruptions on U.S. inflation. Since the inflationary effect of particular commodities is time-varying, our main contribution is to construct a Cost-Push Commodity factor through a genetic algorithm which...

In this paper we test for the presence of bubbles in the Nasdaq stock market index over the period 1994–2003 applying fractional integration techniques and allowing for structural breaks and non-linear adjustments of prices to dividends. The results show a significant structural break in 1998...

This paper examines the long-run dynamics and the cyclical structure of the US stock market using fractional integration techniques. We implement a version of the tests of Robinson (1994a), which enables one to consider unit (or fractional) roots both at the zero (long-run) and at the cyclical...

We analyse in this article the size and the power properties of differentgeneralizations of the KPSS-tests proposed by Hobjin et al. (1998) for testingthe null hypothesis of stationarity in univariate time series when thealternatives are of a fractional form. We show that the test based on the...