Investigation of the nonlinear behaviour in real exchange rates in developing regions

This article examines whether the purchasing power parity (PPP) theory holds or not for the economies in different developing regions located in Africa, Asia and Latin America. In order to investigate this issue, a nonlinear panel unit root test is used to determine if some or all of the real exchange rates in a panel follow a stationary exponential smooth transition autoregressive process. By applying the nonlinear panel unit root test, our results demonstrate an empirical support for the theory of PPP for the economies in developing regions.     

The behavior of Turkish exchange rates: A panel data perspective

This paper investigates the behavior of Turkish exchange rates within the context of purchasing power parity (PPP) hypothesis by means of recent developments in the panel unit root testing procedures for ten Turkish real exchange rates during January 2002–May 2012. The unit root test which accounts for nonlinearity, smooth structural shifts, and cross-section dependency supports that PPP hypothesis holds for Eurozone and European countries (Denmark, Norway, Sweden, Switzerland, and United Kingdom), while it does not hold for non-European trading partners (Canada, Japan, Saudi Arabia, and USA). From the empirical results, we can conclude that PPP hypothesis holds in the countries which have the free trade agreement, while it is violated in the countries in which there are trade barriers and greater distance. The findings therefore provide policy implications for Turkey in determining equilibrium exchange rates with her major trading partners.     

Panel asymmetric nonlinear unit root test and PPP in Africa

This study revisits purchasing power parity (PPP) theory for 20 African countries using panel asymmetric nonlinear unit root test proposed by Emirmahmutoglu and Omay (2014), through the sequential panel selection method of Chortareas and Kapetanios (2009). While standard panel unit root tests fail to support the PPP, the empirical results from panel asymmetric nonlinear unit root test do support the PPP. However, additional tests reveal that support in all 20 African countries is mostly due to stationarity of the real effective exchange rates of Ghana and Rwanda where the adjustment process towards equilibrium is nonlinear and asymmetric.     

Removal of farm subsidies in a regional economy: a computable general equilibrium analysis

There are a number of studies that examine the purchasing power parity (PPP) hypothesis. The empirical findings from the extant literature for the PPP hypothesis are mixed. This article applies univariate and panel Lagrange Multiplier (LM) unit root tests with one and two structural breaks to real exchange rates for 15 Asian countries. The univariate LM unit root tests find evidence of PPP for two-thirds of the sample. The results from the panel LM unit root test support long-run PPP for the Asian countries in the sample. The results from the LM panel unit root tests differ from those of existing panel unit root tests of PPP for Asian countries that have not allowed for the existence of structural breaks.     

Testing the theory of PPP for emerging market economies that practice flexible exchange rate regimes

This study aims to test the long-run validity of purchasing power parity by using Fourier quantile unit root and Fourier cointegration analyses for 12 emerging market economies that practice a flexible exchange rate regime. With the Fourier approach, structural breaks are modelled as a gradual and smooth process. Fourier quantile unit root test results show that real exchange rate series are stationary for Colombia, India, Philippines, Poland, South Africa, and Turkey. On the other hand, Fourier cointegration test results reveal that purchasing power parity is valid for Brazil, Colombia, India, Mexico, South Africa, Thailand, and Turkey.     

Purchasing power parity in transition countries: Sequential panel selection method

This study applies the Sequential Panel Selection Method (SPSM), proposed by Chortareas and Kapetanios (2009) to test the validity of long-run purchasing power parity (PPP) for a sample of 14 transition countries, using real effective exchange rates, from 1994 to 2012 (for both monthly and quarterly data). SPSM classifies the whole panel into a group of stationary series and a group of non-stationary series. In doing so, we can clearly identify how many and which series in the panel are stationary processes. Empirical results from the SPSM using the Panel KSS unit root test (Ucar and Omay, 2009) with a Fourier function indicate that PPP holds true for most of these transition countries studied. Our results have important policy implications for these transition countries under study.     

Purchasing power parity and country characteristics: Evidence from panel data tests

We examine long-run purchasing power parity (PPP) using panel data methods to test for unit roots in US dollar real exchange rates of 84 countries. We find stronger evidence of PPP in countries more open to trade, closer to the United States, with lower inflation and moderate nominal exchange rate volatility, and with similar economic growth rates as the United States. We also show that PPP holds for panels of European and Latin American countries, but not for African and Asian countries. Our findings demonstrate that country characteristics can help explain both adherence to and deviations from long-run PPP.     

Non-linear quantile unit root test and PPP: more evidence from Africa

It is now a common practice to establish stationarity of the real exchange rate as a sign of purchasing power parity (PPP) hypothesis. In this article, we consider the real effective exchange rates of 29 African countries. When we apply conventional linear unit root tests, we find support for the PPP in eight countries. However, when we shift to the newly introduced non-linear quantile unit root test, support for the PPP increases to 15 countries.     

The real exchange rate,regime changes and volatility shifts

We make use of a data-set with both long span and high frequency to test for purchasing power parity (PPP) while allowing for a structural shift in the volatility of the Mexico–US bilateral real exchange rate (RER). The Kim, Leybourne and Newbold (2002) unit root test, robust to changes in the innovation variance, indicates mean stationarity of the monthly RER, and hence evidence of PPP, for the full sample, 1930–2012, and various subsamples. The persistence of deviations of the real rate from its PPP level as measured by half-lives ranges from 1.37 to 2.41 years.     

汇率非线性因素在部分亚洲货币汇率中的特征——检验购买力平价论的新方法

当真实汇率运动实际上是非线性过程,而假设它为线性时,那么检验购买力评价理论的标准单位根检验通常是低效力的。文章运用带有单位根的门限自回归模型模拟了包括中国在内的6个亚洲主要新兴市场国家货币兑美元的真实汇率,发现它们都具有较强的非线性,说明了传统的线性方法不再具备模拟真实汇率的能力,且除人民币以外的其他5种货币的真实汇率都表现出了平稳非线性特征,在异动时期具有均值回归的趋势。周期性的金融危机是导致中国以外的其他5个国家货币的真实汇率出现异动的主要因素。人民币真实汇率的非线性行为则表现出了与其他国家不同的特点,导致它出现异动的主要因素为人民币对内和对外价格的相互背离,人民币真实汇率没有表现出向均值调整的趋势,甚至在异动时期呈现了向均值偏离的趋势。     

An empirical test of purchasing power parity in selected developing countries: a panel data approach

Abstract

This paper examines the empirical validity of Purchasing Power Parity (PPP) for certain large developing economies by using a panel unit root methodology. The test results show that a long run real exchange rate depreciation trend exists in certain developing countries. Without considering this depreciation trend, it is hard to verify the stationarity and to explain the existence of the extremely long half-lives of the real exchange rates. When a linear time trend is included in the tests, the results tend to support the stationarity of the underlying real exchange rate processes, and the half-lives are significantly shorter and their range can be explained by transitory disturbances.     

Reexamining the PPP hypothesis: A nonlinear asymmetric heterogeneous panel unit root test

In this study, we re-examine the PPP hypothesis in the light of the new developments in the unit root testing literature. The recent theoretical findings have pointed out that the real exchange rate series exhibit asymmetric nonlinear behavior. A unit root test applied to analyze the PPP hypothesis therefore, should also take into account this asymmetry inherent in the real exchange rate. Different unit root tests that consider the presence of these data features have been developed in the time series literature. However, a true attempt to test the PPP hypothesis should take a panel data approach. To this end, we propose a nonlinear heterogeneous panel unit root test where the alternative hypothesis allows for symmetric or asymmetric exponential smooth transition autoregressive nonlinearity and provide its finite sample properties. We apply our test to the real exchange rates of the 15 European Union countries against the US dollar. While the results of the linear and symmetric nonlinear heterogeneous panel unit root tests are against the PPP hypothesis, the asymmetric nonlinear heterogeneous panel test that we propose gives support for the PPP hypothesis as expected. Therefore, the conclusions drawn from the linear panel unit root tests or the nonlinear panel unit root tests that do not take asymmetry into account might be misleading.     

Testing a theoretical model of mortgage demand on UK data

This study explores whether the long-run purchasing power parity (PPP) hypothesis holds for selected real exchange rates from Turkish economy during the period 1982M1–2003M12. In addition to conventional unit root tests, five different unit root test procedures have been applied including efficient point-optimal tests, extended M tests and GLS-detrended variants of DF tests, to four monthly real exchange rate series defined in terms of both producer and consumer price indices. The countries analysed are the USA, the UK, Germany and Italy which are major trade partners of Turkey. Mixed evidence is found for the long-run PPP hypothesis when real exchange rate is defined in terms of German DM and Italian Lira. However, the empirical analysis reveals that the PPP hypothesis holds strongly in the long-run for the UK£ and US$ based real exchange rates series using either PPI or CPI. In corroboration with other studies in the literature, the bias correlated half-life estimates suggest relatively faster speeds of adjustment supporting the view that the deviations from the PPP rate dissipate rather quickly for relatively high inflation countries.     

A managerial model of investment: overlooked alternatives

The long-run purchasing power parity (PPP) hypothesis is tested for nine bilateral sterling exchange rates, using recently developed techniques on cointegration and seasonal integration. The empirical findings show that none of the exchange rates and relative prices contain seasonal unit roots, but all have an autoregressive unit root. The cointegration tests overwhelmingly reject the PPP hypothesis as a long-run equilibrium condition for all countries concerned.     

Revisiting purchasing power parity in Latin America: sequential panel selection method

This study applies the Sequential Panel Selection Method (SPSM), proposed by Chortareas and Kapetanios (2009) to test the validity of long-run purchasing power parity (PPP) in a sample of 15 Latin American countries using monthly data spanning from December 1994 to February 2010. SPSM classifies the whole panel into a group of stationary and nonstationary series. In doing so, we can clearly identify how many and which series in the panel are stationary processes. Empirical results from the SPSM using the Panel KSS unit root test (Ucar and Omay, 2009) with a Fourier function which accounts for any structural break in the data indicate that PPP holds in many of the Latin American countries studied.     

Short-run exchange rate uncertainty in Latin America

This paper to obtain an ex ante measure of exchange rate uncertainty in 11 Latin American countries. As a preliminary issue, the purchasing power parity (PPP) condition is tested using Engle and Granger two-step procedure and Johansen method. The argument is that exchange rate uncertainty could be lower if PPP holds in the long run. The expected exchange rate uncertainty is estimated according to an extended version of the autoregressive, conditionally heteroscedastic (ARCH) model. The results show that the ARCH adjusment produces more efficient estimates in seven countries and that the acceptance of PPP has little effect on exchange rate uncertainty.     

Re-examining the real interest rate parity hypothesis (RIPH) using panel unit root tests with asymmetry and cross-section dependence

This paper investigates the validity of the real interest rate parity hypothesis (RIPH) using a panel unit root approach. For this purpose, first we estimate the possible nonlinear data-generating processes of the real interest rate differential series and using these estimates determine which panel unit root test is better for analyzing the RIPH. To this end, smooth transition autoregressive and threshold autoregressive (TAR) models are estimated for two different panels of countries: G7 and post-Soviet transition economies. The results show that the data displays both strong asymmetry and high transition speed. Therefore, secondly, we propose a new panel unit root test where the alternative is stationary with asymmetric TAR adjustment, and provide their empirical power properties. Finally, we demonstrate that our newly proposed test is able to provide conclusive evidence in favor of the RIPH in contrast to the other panel unit root tests considered.     

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.     

Parity reversion persistence in real exchange rates: middle income country case

This article investigates purchasing power parity (PPP) in the specific context of middle income countries. To circumvent the low power of traditional stationarity tests (Augmented Dickey-Fuller and Phillips-Perron tests), it performs variance ratio and fractional integration tests in addition to Perron's test that accounts for potential structural changes in real exchange rate processes. Beyond estimating half-life shocks to PPP, this article attempts to explain these estimates using a set of country specific variables as suggested by economic theory. The evidence suggests that reversion to parity tends to be faster in high inflation countries and that productivity improvement leads to a higher level of persistence. Openness to trade tends to reduce the extent of deviations from parity but this result does not appear to be statistically robust. Evidence shows also that deviations are less persistent under a fixed exchange rate regime and under unrestricted capital mobility.     

Purchasing power parity across Mexican cities: a panel data analysis

This article presents three different unit root tests for panel data, the main objective is to find the level of internal integration market through the purchasing power parity (PPP) evidence, based in the Balassa–Samuelson approach. Thus, eight kinds of markets, as tradable and nontradable goods for 16 main Mexican cities during a 21 year period have been contrasted. While two tests showed the PPP validity for seven markets, the other rejected it. The results obtained moreover feed the present controversy about which test is most appropriate to test the PPP, as soon as it is highlighted new elements emerge to explain the half-life analysis.