Quantile unit root test and the PPP in Africa

In this study, we apply the Quantile unit root test and revisit the Purchasing Power Parity (PPP) in 20 African countries using real effective exchange rates over the period 1971Q1 to 2012Q4. While traditional unit root tests fail to reject unit root hypothesis in most of the countries, results from Quantile unit root test reject unit root null hypothesis in Ghana, Mauritius, Niger, South Africa, and Togo, providing support for the PPP at least in these five countries. We further estimate the half-life based on Quantile autoregressive (QAR) model to be about 4.57–7.96 quarters (1–2 year).     

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.     

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.     

Testing the validity of PPP theory for African countries

This study examines the purchasing power parity theory for 14 African countries by applying a recent composite time series method that incorporates the Fourier approximation. The structural breaks are modelled as a gradual smooth process by means of a Fourier component. The Fourier unit root test failed to find any evidence showing that real exchange rates for these 14 countries have mean-reverting tendencies. However, both cointegration and Fourier cointegration tests detect a stable long-term relation between the nominal exchange rate and relative price levels for 8 out of 14 countries; moreover, for five countries Fourier component in cointegration analysis is found to suit quite well.     

Purchasing Power Parity and the European single currency: Some new evidence

The effect of the single currency on the Purchasing Power Parity (PPP) hypothesis is examined in this study for the 15 EU countries, vis a vis the US dollar, before and after the advent of the euro. Standard as well as nonlinear unit root tests are employed on the time series dimension. Unit root tests reject PPP and the highest half-lives are observed after the introduction of the single currency. Panel unit root (Pesaran, 2007) and stationarity tests (Hadri and Kurozumi, 2008) that take into account cross-sectional dependence are also estimated. The results remain inconclusive as panel stationarity tests fail to support PPP whereas panel unit root tests fail to reject PPP for the whole sample and for the period before the introduction of the single currency.     

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.     

The dynamics of the growth of firms: evidence from the services sector

Using a dynamic panel data model with serial correlation in the error term, the purpose of this paper is to examine if Gibrat’s Law can be rejected for the services sector as it has been for manufacturing. The aim of this paper is also to improve the understanding of the empirical determinants of firm growth by extending the literature to include a new variable related to foreign participation. In addition, and based on recent developments in the growth of firms, our analysis also includes the role of the financial structure. The sample used is an unbalanced panel data set that includes all size classes, including the smallest surviving firms, from the Portuguese service sector over the period from 1995 to 2001. Applying the GMM-system estimator our findings suggest that Gibrat’s Law is rejected for the services firms. In addition, the results also indicate that firm growth is mainly explained by firm size and age. These results have significant policy implications.

Capital-enhanced equilibrium exchange rate: evidence from India

This article examines the validity of the capital-enhanced equilibrium exchange rate (CHEER) approach using quarterly data ranging from 1993Q1 to 2016Q2. Using unit root break test and structural break cointegration technique, our overall results indicated that the CHEER is invalidated once a structural break is accounted for in the cointegration relationship. The rejection of the validity could be attributed to the asymmetry in the capital flows and exchange rates being not fully flexible.     

The inflation rates may accelerate after all: panel evidence from 19 OECD economies

The stationarity of inflation has many important economic implications. Most panel-based empirical studies do not handle cross-sectional dependence, which will result in power distortion. This paper applies a nonlinear IV estimator to calculate the test statistic of panel unit root (Chang in J Econom 110:261–292, 2002), which accounts for general cross-sectional correlation. Using monthly inflation rates, two statistics proposed by Im et al. (J Econom 115:53–74, 2003) reject the unit root; however, the nonlinear IV statistic accepts the unit root. That is, the ignored cross-sectional correlation may lead to over-rejection of the unit root null. In a nutshell, unlike current literature, the inflation rates may accelerate after all.     

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 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.     

Real interest rate parity in Asian countries: evidence from the quantile unit root test

This article studies the real interest rate parity (RIP) for several Asian countries. This is done by examining the stationarity in the real interest rate differentials (rids) with respect to the US using the quantile unit root test. Our results show that rids exhibits unit-root behaviours in the lower quantile levels, and mean reversion in the upper quantile levels. Furthermore, large positive shocks tend to induce strong mean reversion and the adjustment towards the long-run equilibrium level is faster as rids gets larger, with shorter half-lives in the extreme quantile levels.     

Mean reverting financial leverage: theory and evidence from Pakistan

Grounding concepts of the two competing theories of capital structure (trade-off theory, pecking order theory) are quite opposite to each other. Trade-off theory claims that there is an optimal (target) capital structure and firms try to achieve that optimal (target) point. Whereas pecking order theory argues that there is no optimal (target) capital structure but the firms follow a specific pattern of financing. Using the two competing theoretic frameworks, this study applies Fisher-type panel unit root test to an unbalanced panel data of 13 115 firm-year observations of nonfinancial firms listed on Karachi Stock Exchange Pakistan spread over 38 years (1973–2010). Overall panel test results, for short-term, long-term, as well as total leverage support trade-off financing behaviour while individual firm results do not. Individual firm results show that only 16% of the firms have short-term target, 25% of the firms have long-term target and 12% of the firms have total target leverage ratio. Further, industry results explain that most of the industries do have target leverage ratios and classification of data into profitable and lossmaking firm-year observations explains that profitable firms clearly follow trade-off financing behaviour while the results for lossmaking firms do not support trade-off financing behaviour. Our study indicates that it is important for the government to ensure policies to develop well-balanced financial markets and to improve accountability systems.     

PPP test for Asian countries and regions: new evidence from a wild bootstrap AESTAR test

This article investigates the effects of time-varying variance on the asymmetric exponential smooth transition autoregressive (AESTAR) unit root test. We propose a wild bootstrap-based implementation of the test, which is asymptotically valid under time-varying variance. We apply our proposed method to test the Purchasing Power Parity (PPP) hypothesis for Asian countries and regions, and find that our proposed test provides stronger evidence against the PPP hypothesis than the conventional AESTAR test.     

PPP in the 34 OECD countries: evidence from quantile-based unit root tests with both smooth and sharp breaks

Conventional unit root tests have mostly failed to validate the PPP. Quantile-based unit root tests by previous research have provided some support for the PPP. In this article, we take an additional step and incorporate sharp shifts and smooth breaks into the quantile-based unit root test and re-examine the PPP in each of the 34 OECD countries over the period 1994:01–2016:03. We find support for the PPP in 18 countries of Austria, Chile, Estonia, Finland, France, Germany, Italy, Korea, Mexico, Netherlands, New Zealand, Poland, Portugal, Slovenia, Sweden, Switzerland, Turkey and the United Kingdom.     

Inflation-targeting and real interest rate parity: A bias correction approach

This paper investigates whether inflation-targeting influences real interest rate parity (RIP) by a bias correction approach under cross-sectional dependence. The recursive mean adjustment (RMA) method proposed by So and Shin (1999) and Shin and So (2001) is employed to correct the downward bias in the panel unit root tests and in the half-life estimates of real interest rate differentials for traded and non-traded goods. The empirical findings differ depending on whether we apply the RMA. More importantly, the empirical results show that as more homogeneous economies become involved in terms of inflation-targeting regime, stronger mean reversion and much a tighter confidence interval are present. Thus, inflation-targeting plays an important role in providing favorable evidence for long-run RIP.     

Unemployment persistence in EU countries: new evidence using bounded unit root tests

We apply a series of bounded unit root tests to revisit the unemployment persistence in eight European Union (EU) countries. We find strong evidence in favour of the hysteresis hypothesis in all the cases. This result can be explained by a reduced labour mobility, a decreasing wage inflation and a high uncertainty regarding the future level of unemployment in the EU countries.     

The effect of the Internet on economic growth: Evidence from cross-country panel data

Using cross-country panel data, we found evidence that the Internet plays a positive and significant role in economic growth after investment ratio, government consumption ratio, and inflation were used as control variables in the growth equation.