the emphasis of this paper is the role of volatility indices on improvement artificial neural networks (anns) forecasting models for the daily usd/eur and usd/gbp exchange rates two volatility indices are used. first; the realized volatility, which is based on intra-daily data, and second the garch volatility. they are applied into the model in two ways. firstly, the lagged volatility index is ...

The gravity map of Ouaddai in the eastern region Chad exhibits important anomalies that are often delimitated by high gradients, resulting from density contrasts between various anomaly sources. This presumes an tectonic activity zone. Because its arid and desert nature, is water-poor or even lacking water resources. main source made very deep aquifers. analysis this study helps to better under...

Over the past 15 years there has been remarkable progress in the specification and estimation of dynamic stochastic general equilibrium (DSGE) models. Central banks in developed and emerging market economies have become increasingly interested in their usefulness for policy analysis and forecasting. This paper reviews some issues and challenges surrounding the use of these models at central ban...

The problem of measuring the precision of signals generated by fundamental macroeconomic models is not trivial. In this paper, we suggest three different approaches for the estimation of the true and unknown distribution of the population signal. We apply the bootstrapping procedure described by Efron and Tibshirani (Stat. Sci. 1 (1986) 54) to estimate the empirical distribution of the signal a...

The non-stereospecific α-haloalkanoic acid dehalogenase E (DehE) degrades many halogenated compounds but is ineffective against β-halogenated compounds such as 3-chloropropionic acid (3CP). Using molecular dynamics (MD) simulations and site-directed mutagenesis we show here that introducing the mutation S188V into DehE improves substrate specificity towards 3CP. MD simulations showed that resid...

This paper provides a synthesis and further development of a global modelling approach introduced in Pesaran, Schuermann and Weiner (2004), where country specific models in the form of VARX* structures are estimated relating a vector of domestic variables, xit, to their foreign counterparts, x*it, and then consistently combined to form a Global VAR (GVAR). It is shown that the VARX* models can ...

In this paper, I develop a theoretical model to analyze the optimal choice between bank loans and bond finance for a sovereign debtor. The model describes a market that is subject to moral hazard and adverse selection. I model the choice between the two debt instruments allowing for debt renegotiation in the event of financial distress, with the possibility of default. The model incorporates pr...

Identification of New Keynesian Phillips Curves from a Global Perspective New Keynesian Phillips Curves (NKPC) have been extensively used in the analysis of monetary policy, but yet there are a number of issues of concern about how they are estimated and then related to the underlying macroeconomic theory. The first is whether such equations are identified. To check identification requires spec...

The recent financial turmoils in Latin America and Europe have led to a concatenation of several events from currency, banking and sovereign debt crises. This paper proposes a multivariate dynamic probit model that encompasses the three types of crises ’currency, banking and sovereign debt’ and allows us to investigate the potential causality between all three crises. To achieve this objective,...