DO AFRICAN COUNTRIES MOVE ASYMMETRICALLY TOWARDS PURCHASING POWER PARITY?

This paper investigates the possibility that the adjustment towards long‐run relative purchasing power parity (PPP) is dependent upon the nature of deviations from PPP that are experienced. While existing studies involving developed and less developed countries often find against PPP having employed linear tests of non‐stationarity or non‐cointegration, we employ a new cointegration test, recently advocated by Enders and Siklos and Enders and Dibooglu, that tests for an asymmetric adjustment towards parity with respect to positive and negative deviations of the real exchange rate from its equilibrium value. Using a sample often African economies with data taken from the post‐Bretton Woods floating exchange rate era, long‐run PPP holds in eight of these cases if an explicit distinction is made between positive and negative deviations. Across the sample, we find variation in the type of asymmetry experienced and the roles played by price and nominal exchange rate adjustment.     

PPP: <Emphasis Type="Italic">Delusion</Emphasis> or <Emphasis Type="Italic">Reality</Emphasis>? Evidence from a Nonlinear Analysis

In this paper we analyze the validity of the purchasing power parity (PPP) in a nonlinear framework using data for 18 bilateral US dollar exchange rates. Following Enders and Ludlow (2002), we use unit root and cointegration tests that do not assume a specific nonlinear adjustment. We find evidence of non-linear mean reversion in deviations from the PPP equilibrium in 11 out of 18 currencies. Additionally, to disentangle the respective contribution of exchange rate and prices to the adjustment toward the long run equilibrium, we estimate a Vector Error Correction Model. According to our empirical analysis, there exists a nonlinear mechanism to correct for deviation from the PPP equilibrium that comes mainly from the exchange rates. This is consistent with theoretical arguments on international goods markets under transaction costs as well as with an emerging strand of empirical literature. These results highlight the importance of neglecting the possibility of nonlinearity in the debate about the PPP and provide empirical evidence that supports the scenario of the PPP hypothesis as a reality.     

PURCHASING POWER PARITY WITH RANK TESTS FOR NONLINEAR COINTEGRATION IN AFRICAN COUNTRIES

This study applies nonlinear cointegration to assess exchange rates with the corresponding relative prices and aggregate price levels for 20 African countries. We find that a nonparametric rank test has higher power than parametric testing procedures; a true data‐generating process of exchange rate is in fact a stationary nonlinear process. We examine the validity of purchasing power parity (PPP) from the nonparametric nonlinear point of view and provide robust evidence that clearly indicates PPP holds true for these countries. Hence, the long‐run African countries exchange rate adjustments are in equilibrium with the relevant fundamentals as suggested by the PPP hypothesis in a nonlinear way.     

Testing the Marshall–Lerner Condition in Kenya

In this paper we examine the Marshall–Lerner (ML) condition for the Kenyan economy. In particular, we use quarterly data on the log of real exchange rates, export/import ratio and relative (US) income for the time period 1996q1‐2011q4, and employ techniques based on the concept of long memory or long‐range dependence. Specifically, we use fractional integration and cointegration methods, which are more general than standard approaches based exclusively on integer degrees of differentiation. The results indicate that there exists a well‐defined, cointegrating relationship linking the balance of payments to the real exchange rate and relative income, and that the ML condition is satisfied in the long run, although the convergence process is relatively slow. They also imply that a moderate depreciation of the Kenyan shilling may have a stabilising influence on the balance of trade through the current account without the need for high interest rates.     

Prospects for a Monetary Union in the East Africa Community: Some Empirical Evidence

This paper examines generalised purchasing power parity (G-PPP) and business cycle synchronisation in the East Africa Community with the aim of assessing the prospects for a monetary union. The univariate fractional integration analysis shows that the individual series exhibit unit roots and are highly persistent. The fractional bivariate cointegration tests suggest that there exist bivariate fractional cointegrating relationships between the exchange rate of the Tanzanian shilling and those of the other EAC countries, and also between the exchange rates of the Rwandan franc, the Burundian franc and the Ugandan shilling. The Fractionally Cointegrated Vector AutoRegressive (FCVAR) results imply the existence of a single cointegrating relationship between the exchange rates of the EAC countries. On the whole, there is evidence in favour of G-PPP. In addition, there appears to be a high degree of business cycle synchronisation between these economies. On both grounds, one can argue that a monetary union should be feasible.     

The stock market and the ringgit exchange rate: a note

This paper presents and tests an augmented monetary model that includes the effect of stock prices on the bilateral exchange rates. The model is applied to the ringgit/US dollar (RM/US) and ringgit/Japanese yen (RM/JY) exchange rates. The empirical analysis is conducted by the Johansen method of cointegration. Using the data from the recent float that ends with 1996:Q4, the study is motivated, among others, by an interesting preliminary finding that although the augmented monetary model is cointegrated, it is subject to parameter instability and that the parameter time dependency can be attributed at least partly to a particular subset of the variables in the system including stock prices. We find that a restricted VAR model which imposes exogeneity restrictions on I(1) variables, such as stock prices, among others, exhibits both cointegration and parameter stability. In addition, we demonstrate that exchange rate adjusts to clear any disequilibrium in the long-run relationship. The empirical findings tend to suggest that the equity market is significant in affecting the exchange rate and in explaining at least in part the parameter instability evidenced in the cointegrating system. Hence, we conclude that models of equilibrium exchange rate should be extended to include equity markets in addition to bond markets.     

Purchasing Power Parity: Error Correction Models and Structural Breaks

This paper examines purchasing power parity (PPP) behavior using error correction models (ECM) and allowing for structural breaks. We distinguish four different objectives: first, this paper examines which variable or variables (the exchange rate and/or international relative prices) exhibit a significant error correction mechanism. Second, this paper presents empirical evidence about the adjustment velocity to the long-run equilibrium. Third, it examines the evidence regarding cointegration and the adjustment coefficients parameter instability, and finally, it analyzes whether traded and non-traded sectors exhibit different behavior. The most important results are: (1) the predominant adjustment is in the exchange rate with a larger velocity adjustment than in relative prices; (2) the evidence suggests that when there are strong depreciations or appreciations in the exchange rate, the international relative prices adjust (i.e., there is evidence of pass-through); (3) the dynamic adjustment to equilibrium is, in general, stable.     

Real exchange rates and unit root tests

Real Exchange Rates and Unit Root Tests. — This paper examines monthly OECD exchange rate data (1979–1997) using univariate and panel data unit root tests. Some of these tests support the hypothesis of a unit root. But tests of cointegration reveal the existence of weak purchasing power parity relationships between bilateral nominal exchange rates and relative prices. We suggest that researchers need not conduct unit root tests on real exchange rate data when a modified version of PPP is used; or if there is a long enough time series. Given the definition of real exchange rates, the indicator should be stationary and should have intrinsic mean reverting behaviour.     

Real Exchange Rate Dynamics in the Asian Economies: Can Regime Shifts Explain Purchasing Power Parity Puzzles?

Abstract

We show that the strong version of the purchasing power parity (PPP) hypothesis holds in most of the US dollar real exchange rates using cointegration method that accounts for breaks in the models. The break dates in seven of the Asian currencies coincide with the two rounds of currency depreciation recorded during the 1997–1998 financial crises. We obtain a mean half-life estimate of about 10 months for PPP to converge to its long-run equilibrium level. Our confidence intervals based on persistence profile approach for the half-lives is much narrower than previous evidence might indicate. Taken together, these results show that mean reversion is stronger than commonly thought.     

Testing for cointegration with threshold effect between stock prices and exchange rates in Japan and Taiwan

This paper empirically investigates the exchange rate effects of the New Taiwan dollar against the Japanese Yen (NTD/JPY) on stock prices in Japan and Taiwan from January 1991 to Mach 2008. Our study employs the newly threshold error-correction model (TECM) elaborated by Enders and Granger [Enders, W., Granger, C.W.F., 1998. Unit-root tests and asymmetric adjustment with an example using the term structure of interest rates. Journal of Business Economics & Statistics 16, 304–311] and Enders and Siklos [Enders, W., Siklos, P.L., 2001. Cointegration and threshold adjustment. Journal of Business Economics & Statistics 19, 166–176], assuming the nature of the relationship between the variables is on the basis of non-linearity. The empirical evidence suggests that there is a long-run equilibrium relationship between NTD/JPY and the stock prices of Japan and Taiwan during the time period investigated. However, an asymmetric threshold cointegration relationship only exists in Taiwan’s financial market. Furthermore, we extend our research by taking into account the effect of the U.S. exchange rate specifically on Taiwan’s financial market. This research also finds a long-term equilibrium and asymmetric causal relationships between NTD/USD and the stock prices of Taiwan. In addition, the results of TECM Granger-Causality tests show that no short-run causal relationship exists between the two financial assets considered for both countries’ cases. However, in the long run a positive causal relationship running from either the Japan or U.S. exchange rate to the stock prices of Taiwan strongly argues for the traditional approach.     

Cointegration Tests of Purchasing Power Parity: the Case of the Thai Baht*

This paper will examine the validity of the purchasing power parity (PPP) hypothesis for the Thai baht vis-à-vis the currencies of Thailand's key trading partners under the new exchange rate regime using the cointegration technique. The major conclusions obtained from this empirical analysis may be broadly summarized as follows. First, the empirical evidence, based on the DF and ADF statistics, seems to suggest that the nominal exchange rates and relative prices are well characterized as non-stationary I(1) processes. Second, the cointegration analysis provides no evidence in support of a long-run equilibrium relationship between bilateral nominal exchange rates for the Thai baht vis-à-vis the currencies of Thailand's major trading partners and the corresponding relative price ratios. This implies rejection of PPP for these countries. If this is the case, considerable care should be taken in assessing the long-run implications for the real exchange rate, and thus competitiveness against Thailand's key trading partners, of shocks to the nominal exchange rate.     

Bayesian analysis of a Markov switching temporal cointegration model

This paper introduces a Bayesian approach to a Markov switching cointegration model that allows the cointegration relationships to be switched on and off depending on the regime. Unlike a classical method for nonlinear cointegration model that uses the cointegrating vector based on a linear cointegration model, the proposed Bayesian method allows for estimation of the cointegrating vector within a nonlinear framework conditional on the regime variables through the Gibbs sampling so that it generates more reliable estimation. The Bayes factors are applied to test for Markov switching and model specifications. The purchasing power parity (PPP) relationship between UK and US is investigated using the proposed model for illustration.     

Testing purchasing power parity for Japan and the US: A structural-break approach

In this work we empirically assess the weak and strong forms of purchasing power parity (PPP) hypothesis for the economies of Japan and US. Monthly data for the, traded-goods price indices and the JPY/USD exchange rate are employed for the, period from January 2000 to October 2012. This period includes large shocks, such as, the US subprime crisis and the 2011 Tsunami in Japan. We take into account possible, structural shifts and breaks by employing the class of Lee and Strazicich, 2003, Lee and Strazicich, 2004 unit, root tests. Empirical analysis suggests that a break corresponding to the start of the US subprime crisis is not rejected. Furthermore, utilizing the Gregory and Hansen (1996) and, Hatemi (2008) cointegration methodologies, the weak form of PPP is not rejected. We, also test the strong PPP hypothesis by using Dynamic Ordinary Least Squares, (DOLS). The empirical evidence rejects the strong form of PPP for the period, preceding the US subprime crisis in contrast to the period after.     

Forecasting the Euro exchange rate using vector error correction models

Forecasting the Euro Exchange Rate Using Vector Error Correction Models. — This paper presents an exchange rate model for the Euro exchange rates of four major currencies, namely the US dollar, the British pound, the Japanese yen and the Swiss franc. The model is based on the monetary approach of exchange rate theory which uses fundamental macroeconomic variables to explain the exchange rate. A crucial point when using such a model is its proper estimation through cointegration analysis. The euro exchange rate model is therefore estimated in the form of a Vector Autoregressive (VAR) model with cointegrating vectors (VECM). We find that when cointegration analysis is undertaken properly, the naive random walk prediction can be out-performed for the US dollar, the British pound and the Japanese yen, but not for the Swiss franc.     

人民币均衡实际汇率研究:1978—2009

文章在总结了国内已有的关于人民币均衡汇率水平研究的基础上,以均衡实际汇率理论为依据,考虑中国实际国情和已有相关文献研究的结论,对均衡实际汇率模型进行了部分修正,筛选出人民币实际有效汇率的最优解释变量,并采用协整方法和H-P滤波技术,实证测算人民币均衡汇率水平,在此基础上,对改革开放以来尤其是2005年汇改之后人民币汇率失调情况进行深入分析,并对2005年汇改后央行出台的人民币汇率政策进行简单评估。     

The Chinese economies in global context: The integration process and its determinants

The linkages between the People's Republic of China and the other Chinese economies of Hong Kong and Taiwan are assessed, and compared against those with Japan and the US. We first characterize the time series behavior of three criteria of integration, namely real interest parity, uncovered interest parity, and relative purchasing power parity. There is evidence that these parity conditions tend to hold over longer periods between the People's Republic of China and all other economies, although they do not hold instantaneously. Overall, the magnitude of deviations from the parity conditions is shrinking over time. Amongst all, however, Hong Kong exhibits indications of a more advanced level of integration with the mainland. We also find that evidence is surprisingly positive for integration with the US. We then turn to examining the determinants of the degree of integration. Regression results suggest that the degree of financial and real integration depend upon the extent of capital controls, foreign direct investment linkages as well as exchange rate volatility. J. Japanese Int. Economies 20 (1) (2006) 128–153.     

PURCHASING POWER PARITY IN AFRICAN COUNTRIES: EVIDENCE FROM PANEL SURADF TEST

This study reexamines the validity of long-run purchasing power parity (PPP) hypothesis using a battery of panel unit root tests for 11 developing countries in Africa over the period 1980-2007. Based on the conventional panel unit root tests, we found evidence that the monthly real exchange rates in these countries were mean reverting. By contrast, the series-specific unit root test proposed by Breuer et al. (SURADF) reveals that only six of the 11 RERs series were stationary using the US dollar as reference currency. Additionally, our results reveal that there is stronger evidence of the parity condition with the Rand-based rates than in the other currency-based rates like the US dollar or Euro. We conclude that PPP holds in some, but not all, of the African countries according to the SURADF tests.     

人民币汇率对进出口贸易的影响研究——基于汇改前后的比较分析

本文运用Johansen协整方法对不同汇率制度环境下人民币汇率对我国进出口贸易的影响效应进行了比较分析,发现汇改前,无论是进口额还是出口额,均与人民币汇率不存在长期均衡关系,而汇改后的出口额却与人民币汇率存在显著的长期协整关系,且人民币汇率升值对出口的抑制效应非常显著。这意味着在研究人民币汇率对进出口贸易的影响效应时尤其不能忽略不同汇率制度环境的影响,所反映的政策含义表明政府当局在制定汇率制度时要保持审慎的态度,以避免人民币升值过快引起对我国出口的抑制效应。     

Long-Run Purchasing Power Parity with Asymmetric Adjustment

Tests of purchasing power parity (PPP) that use panel data are more supportive of the theory than are bilateral tests. The article uses threshold cointegration to explore long-run PPP. Using data from the post-Bretton Woods period, we show that cointegration with threshold adjustment holds for a number of European countries on a bilateral basis. Focusing on France and Germany as base countries, we show that the error-correction model has important nonlinear characteristics in that prices and the exchange rate have markedly different adjustment patterns for positive gaps from PPP than negative gaps.     

台湾地区教育投资的经济增长效应实证研究

从财政性教育投资占GDP的比重、教育投资的层级结构分析和政府教育经费占政府支出比率等角度考察了台湾地区教育经费投资的现状。同时,根据时间序列动态均衡关系分析方法,运用协整理论、误差修正模型等计量分析工具,对1981—2011年台湾地区教育投资与经济增长的关系进行实证研究。结果表明:台湾地区教育投资与经济增长之间具有长期正向的动态均衡关系,教育投资对经济增长具有较强的拉动作用。