Long memory and mean reversion in real exchange rates in Latin America

This article examines the long-run Purchasing Power Parity (PPP) hypothesis for 12 Latin American Real Effective Exchange Rates (REERs) using fractional integration techniques. The empirical results, applying parametric approaches, provide evidence of mean reversion in the REERs in the cases of Nicaragua, Belize, Costa Rica, Guyana and Paraguay and lack of it for the remaining seven countries. Employing semiparametric methods, the evidence of mean reversion covers the following countries: Belize, the Dominican Republic, Ecuador and Mexico. Thus, only for Belize and Guyana do we obtain consistent evidence of mean reversion in the real exchange rates. At the other extreme, lack of mean reversion, and thus, lack of PPP, is obtained with both methods in Bolivia, Brazil, Colombia and Venezuela. For the remaining six countries, the results are ambiguous. The results for the PPP theory in Belize and Guyana may show the importance of promoting policies based on exchange rate flexibility and economic liberalization to reach a long-run stability scenario that leads to greater international competitiveness and lower external vulnerability.     

Fractional Integration of Nominal Exchange Rates: Evidence from CEECs in the Light of EMU Enlargement

This paper uses fractional integration models to describe the long‐run dependence of nominal exchange rates in Central and Eastern European countries (CEECs). The analysis is validated using nonparametric, semiparametric and parametric techniques. From comparing the results across the three approaches, it was clear that mean reversion takes places only for the euro exchange rates in Bulgaria, Estonia, and Slovenia. Other exchange rates based on the euro also display mean reversion with the parametric methods. For the US dollar rates, the unit‐root null hypothesis cannot be rejected in any single country, indicating that shocks affecting the exchange rates against the US dollar are of a permanent nature, while those directed against the euro are less persistent, and tend sometimes to disappear in the long run. Policy implications are derived.     

Threshold,smooth transition and mean reversion in inflation: New evidence from European countries

Knowing the absence or presence of a unit root in inflation is helpful not only in distinguishing between different economic hypotheses but is also important to monetary authorities in implementing the policies of disinflation. Using data for fourteen European countries, this study investigates the issue of nonstationarity in inflation by considering the possibility of nonlinearity. In particular, we consider the properties of a threshold, smooth transition and structural break in testing for a unit root in the inflation rates. By and large, the results support the view that the inflation rates of the European countries are characterized by a unit root process based on the conventional linear unit root tests. However, the results of the nonlinear unit root tests show that the inflation rates are characterized by nonlinear mean reversion after considering the nonlinear properties of the threshold, smooth transition and structural break. The mean reversion in inflation favors the hypothesis of, for example, the natural rate of inflation and the sticky-price model and implies that shocks only have transitory effects.     

ARE LABOUR FORCE PARTICIPATION RATES NON‐STATIONARY? EVIDENCE FROM 130 YEARS FOR G7 COUNTRIES*

This paper applies a unit root test with a non‐linear threshold to examine whether labour force participation rates are mean reverting for G7 countries using annual data over a 130 year period. We find some evidence of mean reversion for just over half the sample; however, this result is sensitive to regime shifts. We also examine whether the labour force participation rate is trend reverting through employing a lagrange multiplier (LM) unit root test with one and two structural breaks in the intercept and slope. The LM unit root test provides no additional evidence in support of stationarity. On the basis of the unit root tests for mean reversion we conclude that there is at best mixed evidence that long‐term changes in unemployment rates translate into long‐term changes in employment rates and that the unemployment rate is a useful indicator of joblessness.     

The purchasing power parity puzzle is worse than you think

The ‘‘purchasing power parity puzzle’’ is the difficulty of reconciling very high short-term volatility of real exchange rates with very slow rates of mean reversion. The strongest evidence of slow mean reversion comes from least squares estimates of first-order autoregressive models of the long-horizon dollar-sterling real exchange rate. Using median-unbiased estimation methods, we show that these methods underestimate the half-lives of PPP deviations, and thus overestimate the speed of mean reversion. When the specification is amended to allow for serial correlation, the speed of mean reversion falls even further. This makes resolution of the purchasing power parity puzzle more problematic.First version received: May 2003/Final version received: July 2004We thank Lutz Kilian, James Lothian, Mark Taylor, and two anonymous referees for helpful comments and suggestions.     

ICT Use in the Developing World: An Analysis of Differences in Computer and Internet Penetration

Using panel data for 161 countries, we explore the determinants of cross-country disparities in personal computer and Internet penetration. We find evidence indicating that income, human capital, the youth dependency ratio, telephone density, legal quality, and banking sector development are associated with technology penetration rates. Estimates from Blinder–Oaxaca decompositions comparing rates in the developed-country total to developing countries (Total, Brazil, China, Indonesia, India, Mexico, and Nigeria) reveal that the main factors responsible for low rates of technology penetration rates in developing countries are disparities in income, telephone density, legal quality, and human capital. In terms of dynamics, our results indicate fairly rapid reversion to long-run equilibrium for Internet use, and somewhat slower reversion for computer use.     

Deviations and mean reversion to purchasing power parity in the Asian currency crisis of 1997

This study analyses the process of mean reversion towards purchasing power parity (PPP) for a sample of Asian countries around the 1997 crisis. It is found that appreciation relative to PPP is evident prior to the 1997 crash period. Correction occurs from 1997 onwards, a period marked by extreme movements in exchange rates with both appreciation and depreciation relative to the PPP rate over relatively short periods. The key result of this paper is that although reversion towards PPP is apparent for mean, though not statistically significant, it is clear that there is a substantial, statistically significant change in variance from 1997 onwards. This result has implications both for economic modelling of crash periods and for appropriate choice of statistical tests.     

THE REAL INTEREST RATE DIFFERENTIAL: INTERNATIONAL EVIDENCE BASED ON NON-LINEAR UNIT ROOT TESTS

This paper aims at testing international parity conditions by using non-linear unit root tests advocated by Kapetanios et al . (2003, KSS). Results from the KSS tests based on 17 countries (G7 and 10 Asian countries) overwhelmingly show that the adjustment of real interest rates towards real interest rate parity (RIP) follows a non-linear process except for the Taiwan, Hong Kong and Philippines relationships with both the USA and Japan. Overall, the empirical results are in favour of RIP using the USA and Japan as the centre countries but only if non-linearities are accounted for in the data-generating process. Our findings confirm that interest rate differentials, like the real exchange rates reported in recent literature, display a non-linear mean reversion process.     

Nominal and real convergence between the CEE countries and the EU: a fractional cointegration analysis

This paper examines the real and nominal convergence between the Central and Eastern European countries and the EU, using fractional cointegration analysis for the period 1980–2003. Fractional cointegration analysis is a flexible methodology, which allows for more subtle forms of mean reversion. The tests performed are those of Geweke and Porter-Hudak. The convergence processes are valid when macroeconomic time series used in the study are fractionally cointegrated. The results indicate that inflation and interest rates series of six sample countries are fractionally cointegrated with those of the EU. Therefore, nominal convergence has been achieved by some of the transition countries, but the equilibrium errors display long memory. Results also indicate that industrial outputs of most countries in the sample are not fractionally cointegrated with that of the EU. The results further indicate that both nominal and real convergence have been achieved only for Hungary.     

The impact of mean reversion model on portfolio investment strategies: Empirical evidence from emerging markets

Investors use mean reversion model to make decisions on which stocks should be taken in their portfolios according to their mean values. The first goal of the paper is to test the validity of the mean reversion model in emerging markets. Second, it aims to determine the best portfolio investment strategy on the validity of the mean reversion model. As a result of panel regression analysis, we find that the mean reversion model is valid in all of the emerging countries in the sample. This result implies that emerging markets are not efficient even in weak form. On the validity of the mean reversion model, we find that Max3–Min3 portfolio has recorded the best performance and contrarian portfolio is the best portfolio investment strategy. The paper makes contribution to the literature in terms of providing the information about which portfolio investment strategy has the best performance on the validity of the mean reversion model.     

Nonlinear adjustment to the mean reversion of consumption–income ratio

This study utilizes a flexible Fourier stationary test, proposed by Becker et al. (2006) to investigate the mean reversion of consumption–income ratio in 16 OECD countries from 1960 to 2010. Empirical results from our flexible nonlinear stationary test show that the mean reversion hypothesis is not rejected for 12 of the 16 OECD countries.     

Virtual and Composite Fundamentals in the ERM

A latent-variable approach is applied to identify the appropriate driving process for fundamental exchange rates in the ERM. From the time-series characteristics of so-called "virtual fundamentals" and "composite fundamentals", a significant degree of mean reversion can be asserted. The relative degree of mean reversion across countries closely corresponds to often assumed degrees of economic integration vis-a-vis Germany as well as documented degrees of credibility of the exchange rate policies pursued. Convergence in fundamentals appears to be larger under the "new" EMS than in the previous years, but has again diminished after German unification and the subsequent widening of the ERM bands in 1993.     

Revisiting the mean reversion of inflation rates for 22 OECD countries

This study applies a flexible Fourier stationary test, proposed by Becker et al. (2006) to investigate the mean reversion of inflation in 22 OECD countries over the period of 1961 to 2011. While traditional unit root tests give us mixed results, empirical results from our flexible Fourier stationary test indicate that mean reversion of inflation holds in all 22 OECD countries. Our results have important policy implications for the 22 OECD countries under study.     

Nonlinear adjustment in the forward premium: evidence from a threshold unit root test

This paper considers testing the mean reversion of the forward premium in a nonlinear framework. In contrast to previous studies, we consider a novel approach that allows for testing for a unit root in the forward premium while explicitly allowing for nonlinearity in the data. Within this approach, we employ bootstrap methods based on threshold autoregressive (TAR) models to investigate whether the 1- and 3-month forward premia for six industrialized countries are mean-reverting. Overall, we are able to reject the null hypotheses of linearity and nonstationarity indicating nonlinear mean reversion. Furthermore, large deviations of the forward premium from its equilibrium band are found to have faster speed of mean reversion than small deviations, which are strongly persistent. In all, the results support the view that the forward premium exhibits mean reversion, but in a special manner not captured by the usual linear tests. Finally, the results have important implications for foreign exchange market efficiency under risk aversion.     

Bootstrapping covariate stationarity tests for inflation rates

This paper investigates the stationarity properties of international inflation rates by bootstrapping two stationarity tests with covariates in Jansson (2004). When the asymptotic critical values are used, the two powerful tests are found to reject the null hypothesis less in the presence of a large negative moving-average (MA) error in inflation. To cope with this problem, a parametric bootstrap scheme is developed and then is investigated by a Monte Carlo study. The simulation results demonstrate that the bootstrap tests display a better control over the empirical rejection rates at finite samples. Furthermore, after applying these tests to the inflation in G-10 countries, we find that one of the two tests using bootstrap critical values yields inferences that differ from when using asymptotic ones, and as a whole, the bootstrap tests consistently provide strong evidence in support of mean reversion in inflation in most countries of the G-10.     

Nonlinearity and stationarity of inflation rates: evidence from the euro-zone countries

Earlier studies hardly reject the hypothesis of a unit root in inflation. Few studies have examined the possibility of nonlinearity in inflation and tested nonlinear stationarity of the inflation rates. This study thus intends to fill the gap. This study utilizes the tests for nonlinearity along with the unit root tests that allow for nonlinearity in the variables to examine the stationarity of inflation rates of 12 European countries that formed the Euro Zone (EZ) later in the sample period. The results suggest that the majority of these countries’ inflation rates can be characterized by mean reversion during the floating exchange rate period. Many of them appear to be nonlinear stationary. This finding is essential in conducting applied economic studies for these countries, when constructing models whose validity relies on whether or not inflation is stationary. The results of this study also imply that shocks to inflation have a transitory effect on inflation in the euro area. Therefore, it would be less costly in exercising the policies of disinflation for the monetary authorities of the euro area than for those of the countries with nonstationary inflation.     

A new approach to testing unemployment hysteresis

This paper proposes a novel approach to testing unemployment hysteresis. It examined the existence of hysteresis in the unemployment rates of four Nordic countries, namely Denmark, Finland, Norway and Sweden, for the period of 2000–2014. The study applied four alternative methods to analyse the data. The best estimation procedure was chosen in a simple and consistent way. As the findings indicated, the ADF test and FADF test failed to reject the null hypothesis of unemployment hysteresis in all four countries. The ADF–SB test produced mixed results: it rejected the null hypothesis of hysteresis for Denmark and Norway, but failed to reject the null hypothesis for Finland and Sweden. The FADF–SB test yielded more consistent findings: it rejected the null hypothesis for all four countries. Furthermore, findings from the F-tests clearly indicated that the FADF–SB test was the best method among the four proposed alternatives. Despite some discrepancies the findings of this study suggest that unemployment in the four Nordic countries had a mean reversion tendency.     

Long memory in the interest rates in some Asian countries

In this paper, the stochastic behavior of short run interest rates in some Asian development countries is examined by means of using fractionally integrated semiparametric techniques. In doing so, a much richer flexibility is allowed in the dynamic behavior of the series not achieved by the classical representations based on I(0) or I(1) processes. The author uses a quasi-maximum likelihood estimation procedure of Robinson [QMLE, 1995a], which has some advantages with respect to other methods. The results show that the orders of integration of the short run interest rates in Singapore and Thailand are strictly below 1, implying mean reversion. On the contrary, the results for Malaysia, South Korea, and Philippines are less conclusive, the values of d oscillating around the unit root case.     

Asymmetry dynamics in real exchange rates: New results on East Asian currencies

This paper provides new evidence on the purchasing power parity (PPP) hypothesis in six East Asian countries. Based on nonlinear unit root tests, we discovered that the results are broadly consistent with the fact that real exchange rates (RERs) follow a nonlinear mean reversion process. We presented new evidence that the adjustment towards the PPP parity is asymmetric (LSTAR process) above and below the equilibrium value in all but one case — the Malaysian ringgit (MYR). The empirical results suggest that it is important that the conventional tests of PPP be amended to take account of asymmetries in the adjustment process in RERs.     

Real interest rates: nonlinearity and structural breaks

Real interest rate is a crucial variable that determines the consumption, investment and saving behavior of individuals and thereby acts as a key policy tool that the central banks use to control the economy. Although many important theoretical models require the real interest rates to be stationary, the empirical evidence accumulated so far has not been able to provide conclusive evidence on the mean reverting dynamics of this variable. To resolve this puzzle we re-investigate the stochastic nature of the real interest rates by developing unit root tests for nonlinear heterogeneous panels where the alternative hypothesis allows for a smooth transition between deterministic linear trends around which stationary asymmetric adjustment may occur. When the newly developed panel unit root tests are applied to the real interest rates of the 17 OECD countries, we were able to uncover overwhelming empirical support in favor of mean reversion in the short-run and long-run real interest rates. Therefore, these results show that the conclusions drawn from a miss-specified test that ignores the presence of either nonlinearity, structural breaks or cross sectional dependence can give quite misleading results about the stochastic behavior of the real interest rates.