The current population in the World has grown beyond the Break-even level of the food supplies, water, clothing and shelter. Techno- commercial systems are also within the utility of developed nations, but beyond the infrastructure and mental orientation of the Developing and Under Developed...

The episodes of stock market crises in Europe and the U.S.A.since the year 2000,and the fragility of the international stock markets,have sparked the interest of researchers in understanding and in modeling the markets’ rising volatilities in order to prevent against crises.Portfolio managers...

In this paper we give the theoretical basis of a possible explanation for two stylized facts observed in long log-return series: the long range dependence (LRD) in volatility and the integrated GARCH (IGARCH). Both these effects can be theoretically explained if one assumes that the data is...

The Asymmetry or counter-cycle nature and its influence on the persistence of the registered unemployment rate is a traditional topic of the economics theory’s analysis. However, studies of the Spanish unemployment done up to now have not dealt with asymmetry. General studies about Spanish...

We argue that the current framework for predictive ability testing (e.g., West, 1996) is not necessarily useful for real-time forecast selection, i.e., for assessing which of two competing forecasting methods will perform better in the future. We propose an alternative framework for...

In this paper we develop tests of functional form that are consistent against a class of nonlinear "smooth transition" models of the conditional mean. Our method is an extension of the consistent model specification tests developed by Bierens (1990), de Jong (1996) and Bierens and Ploberger...

Our study supports the hypothesis of global non-stationarity of the return time series. We bring forth both theoretical and empirical evidence that the long range dependence (LRD) type behavior of the sample ACF and the periodogram of absolute return series and the IGARCH effect documented in...

This article uses models with changes in regime and conditional variance to show the presence of co-movement between the American and the French New Technology indexes, the NASDAQ-100 and the IT.CAC respectively. For the past two years, American and French New Technology stock markets have been...

The paper examines the relationship between UK wholesale gas prices and the Brent oil price over the period 1996-2003. Tests for Unit Roots and Cointegration are carried out and it is discovered that a long run equilibrium relationship between UK gas and oil prices predates the opening of the...

In this paper we propose a goodness of fit test that checks the resemblance of the spectral density of a GARCH process to that of the log-returns. The asymptotic behavior of the test statistics are given by a functional central limit theorem for the integrated periodogram of the data. A...