Testing for PPP in Australia: evidence from unit root tests against nonlinear trend stationarity alternatives

This paper tests for the empirical fulfilment of PPP in Australia (1977-2004). Previous research focuses on the presence of structural breaks and fails to find any support for PPP (Darne and Hoarau, 2008, Henry and Olekalns, 2002). In contrast, we find that the real exchange rate is stationary once we account for a more general specification of the nonlinear deterministic components based on a Chebishev polynomials approximation

Smooth transitions, asymmetric adjustment and unit roots

The aim of this paper is to develop a unit root test that takes into account two sources of nonlinearites in data, i.e. asymmetric speed of mean reversion and structural changes. The asymmetric speed of mean reversion is modeled by means of a exponential smooth transition autoregression (ESTAR) function for the autoregressive parameter, whereas structural changes are approximated by a smooth transition in the deterministic components. We find that the proposed test performs well in terms of size and power, in particular when the autoregressive parameter is close to one

Localization of the valence electron of endohedrally confined hydrogen, lithium and sodium in fullerene cages

The localization of the valence electron of $H$, $Li$ and $Na$ atoms enclosed by three different fullerene molecules is studied. The structure of the fullerene molecules is used to calculate the equilibrium position of the endohedrally atom as the minimum of the classical $(N+1)$-body Lennard-Jones potential. Once the position of the guest atom is determined, the fullerene cavity is modeled by a short range attractive shell according to molecule symmetry, and the enclosed atom is modeled by an effective one-electron potential. In order to examine whether the endohedral compound is formed by a neutral atom inside a neutral fullerene molecule $X@C_{N}$ or if the valence electron of the encapsulated atom localizes in the fullerene giving rise to a state with the form $X^{+}@C_{N}^{-}$, we analyze the electronic density, the projections onto free atomic states, and the weights of partial angular waves

PURCHASING POWER PARITY IN CENTRAL AND EASTERN EUROPEAN COUNTRIES: AN ANALYSIS OF UNIT ROOTS AND NONLINEARITIES

The aim of this paper is to analyse the empirical fulfilment of PPP in a number of Central and Eastern European countries. For this purpose we apply two different unit root tests in order to control for two sources of nonlinearities, i.e. Bierens (1997) and Kapetanios, Shin and Snell (2003). We find that PPP holds in most of these countries once account has been taken of nonlinear deterministic trends and smooth transitions.PPP, Real Exchange Rate, Unit Roots, nonlinearities, Central and East Europe

Unemployment hysteresis, structural changes, non-linearities and fractional integration in European transition economies

In this paper we aim to analyse the dynamics of unemployment in a group of Central and Eastern European Countries (CEECs). The CEECs are of special importance for the future of the European Union, given that most of them have recently become member states, and labour flows have been seen to rise with their accession. By means of unit root tests incorporating structural changes and nonlinearities, as well as fractional integration, we find that the unemployment rates for the CEECs are mean reverting processes, which is consistent with the NAIRU hypothesis, although shocks tend to be highly persistent

Nonlinear trend stationarity of real exchange rates: the case of the Mediterranean countries

The aim of this article is to provide additional evidence on the fulfilment of the Purchasing Power Parity hypothesis in the so-called Mediterranean countries. In order to test for the empirical validity of such hypothesis, we have applied two types of unit root tests. The first group is due to Bierens (1997) who generalizes the alternative hypothesis to nonlinear trend stationariry and, the second is the Leybourne, Newbold and Vougas (1998) approach that uses a nonlinear specification for the intercept and slope in order to detrend the series. The results suggest that the evidence in favour of the Purchasing Power Parity hypothesis increases when we allow for nonlinear alternatives

Fiscal shocks and budget balance persistence in the EU countries from Central and Eastern Europe

This paper analyses the time series properties of the fiscal balance in the 10 EU countries from Central and Eastern Europe. The persistence of shocks in the variable has been analysed by means of unit root tests that account for the possibility of non-linearities and structural changes. The results of the linear and non-linear unit root tests find only mild evidence in favour of the stationarity hypothesis, with asymmetric effects present in a few cases. After controlling for structural changes in the data generation process, the results point to stochastic stationarity of the series. Thus, in spite relatively steady headline figures, the public balance processes exhibit substantial instability in the EU countries from Central and Eastern Europe.Unit roots, structural breaks, budget balance, EU

Inflation persistence: Implication for a monetary union in the Caribbean

In this paper we aim to shed some light on the potential for creating a monetary union in the Caribbean. We analyse the inflation rates for twelve countries using various time series methods. The results show that the inflation rates are mean reverting processes and that there is evidence of a convergence club in inflation rates within the area, which contradicts previous studies. Our contribution implies good news for the creation of a common central bank in the Caribbean.Caribbean, inflation persistence, monetary union and unit roots

Further evidence on the Real Interest Rate Parity hypothesis in Central and Eastern European Countries: unit roots and nonlinearities

This paper analyses the empirical fulfilment of the Real Interest Rate Parity (RIRP) theory for a pool of Central and Eastern European Countries. To do so, we apply the recently developed Ng and Perron (2001) unit root tests, that are corrected versions of existing unit root tests and the Kapetanios et al. (2003) unit root test which generalises the alternative hypothesis to the globally stationary smooth transition autoregression model. Our results point to the existence of evidence in favour of the empirical fulfilment of the RIRP, in particular, when taking into account the possibility of nonlinearities in the real interest rate differential.Real Interest Rate parity, Unit Roots, nonlinearities, Central and East Europe.

Inflation persistence and asymmetries: evidence for African countries

In this paper we aim at testing the inflation persistence hypothesis as well as modelling (using logistic smooth transition autoregressive, LSTAR, models) the long run behaviour of inflation rates in a pool of African countries. In order to do so, we rely on unit root tests applied to nonlinear models, i.e. Kapetanios et al. (2003). The results point to the non-persistence of inflation hypothesis for most of the countries. In addition, the estimated models are stable in the sense that the variable tends to remain in the regime (low inflation or high inflation) once reached and changes between regimes are only achieved after a shock.Inflation, Persistence, Unit Roots, Nonlinearities.