The Target Zone Model, Non-Linearity and Mean Reversion: is the Honeymoon Really Over?

We estimate a target zone model for three ERM exchange rates for 1983–6 and 1987–91 by the method of simulated moments, taking account of the continuous time specification by using daily data with the interruptions of holidays and weekends. Specification tests are unable to reject the model. The estimates imply, however, an essentially linear relationship between the exchange rate and the fundamentals, with a very limited 'honeymoon effect'. Using Monte Carlo simulations, calibrated on the estimates, we find that standard tests for mean reversion of the exchange rate would largely reject the target zone model when, in fact, it held.     

Nonlinear adjustment in the real dollar–euro exchange rate: The role of the productivity differential as a fundamental

In this paper we analyze the influence of productivity differentials in the dynamics of the real dollar–euro exchange rate. Using nonlinear procedures for the estimation and testing of ESTAR models during the period 1970–2009 we find that the dollar–euro real exchange rate shows nonlinear mean reversion towards the fundamentals represented by the productivity differential. In addition, we provide evidence about the ability of this variable to capture the overvaluation and undervaluation of the dollar against the euro.     

Explaining ERM realignments: Insights from optimising models of currency crises

This paper attempts to provide empirical evidence on the determinants of the realignments throughout the European exchange rate mechanism (ERM). Motivated by the implications of optimising currency crisis models, we relate the probability of “crises” to a set of macroeconomic fundamentals. By using a conditional binominal logit model we show that regime switches are strongly influenced by movements in industrial production, foreign interest rates, competitiveness and imports as well as in foreign exchange reserves. These findings are consistent with the general propositions of recent currency crises models.     

Evidence on the contrarian trading in foreign exchange markets

This paper investigates the existence and price impacts of contrarian behavior in the foreign exchange markets. By utilizing a nonlinear behavioral model where the chartists and fundamentalists coexist, evidence obtained from two sample periods significantly supports the existence of contrarian trading in the British pound, the Japanese yen and the German mark markets. The contrarian trading can only partially offset the price impacts of trend-followers, therefore the price impact of the chartists as a whole is destabilizing. The ability that the contrarians can counterbalance the extrapolation of the trend-followers differs across markets. Traders in the BP market have the highest tendency to contrarian strategy, which in turn contributes to the least deviations of the BP exchange rates departing from its PPP fundamentals. The fundamentalists' confidence in trade fades during large misalignments, which make the mean reversion function of the fundamentalists weak under the circumstances. We find the magnitudes of interventions will be affected by the price impacts of contrarians and their abilities on market stabilization.     

A non-parametric analysis of ERM exchange rate fundamentals

In this paper we present evidence concerning the number of common stochastic trends in three major ERM exchange rates. The results indicate the presence of a single common trend driving these currencies and from this we suggest that the common trend can be considered as the non-parametric fundamentals for the three selected currencies. Using a non-parametric technique, the Alternating Conditional Expectations (ACE) algorithm, we obtain evidence for the existence of non-linearities for two out of three currencies with a functional form, related to the estimated non-parametric fundamentals, close to the S-shape given by the basic target zone model.      

FEER for the CFA franc

We investigate the behaviour of the real effective exchange rates (REER) of the two CFA franc zone monetary unions?–?CEMAC and WAEMU?–?vis-à-vis their long-run equilibrium paths. A reduced form of the Edwards’ (1989) fundamentals equilibrium exchange rate (FEER) model is estimated using the Johansen's (1995) cointegration methodology, and equilibrium paths and associated misalignments are derived for the period 1970 to 2005. Our results suggest that, for both CEMAC and WAEMU, the fundamentals account for most of the exchange rates’ fluctuation: increases in the terms-of-trade, government consumption and productivity tend to appreciate the exchange rate, while increases in investment and openness tend to depreciate it. At end of 2005, we find no evidence that either the CEMAC or WAEMU REERs were significantly over-valued, which suggests that no exchange rate action is currently needed. Our analysis also reveals significant differences in the fundamentals’ marginal impact, and speed of reversion to equilibrium following a shock, which may raise questions about the desirability of maintaining the same parity for both monetary unions.     

Arbitrage costs and nonlinear adjustment in the G7 stock markets

This article aims to study stock price adjustments towards fundamentals due to the existence of arbitrage costs defined as the sum of transaction costs and a risky arbitrage premium associated with the uncertainty characterizing the fundamentals. Accordingly, it is shown that a two regime Smooth Transition Error Correction Model (STECM) is appropriate to reproduce the dynamics of stock price deviations from fundamentals in the G7 countries during the period 1969 to 2005. This model takes into account the interdependences or contagion effects between stock markets. Deviations appear to follow a quasi random walk in the central regime when prices are near fundamentals (i.e. when arbitrage costs are greater than expected arbitrage profits, the mean reversion mechanism is inactive), while they approach a white noise in the outer regimes (i.e. when arbitrage costs are lower than expected arbitrage profits, the mean reversion is active). Interestingly, as expected when arbitrage costs are heterogeneous, the estimated STECM shows that stock price adjustments are smooth and that the convergence speed depends on the size of the deviation. Finally, using two appropriate indicators proposed by Peel and Taylor (2000), both the magnitudes of under and overvaluation of stock price and the adjustment speed are calculated per date in the G7 countries. These indicators show that the dynamics of stock price adjustment are strongly dependent on both the date and the country under consideration.     

Viewpoint: Towards a solution to the puzzles in exchange rate economics: where do we stand?

Abstract.  This paper provides a selective overview of puzzles in exchange rate economics. We begin with the forward bias puzzle: high interest rate currencies appreciate when one might guess that investors would demand higher interest rates on currencies expected to fall in value. We then analyse the purchasing power parity puzzle: the real exchange rate displays no (strong) reversion to a stable long‐run equilibrium level. Finally, we cover the exchange rate disconnect puzzle: the lack of a link between the nominal exchange rate and economic fundamentals. For each puzzle, we critically review the literature and speculate on potential solutions. JEL classification: F31     

Nonlinear dynamics in exchange rate deviations from the monetary fundamentals: An empirical study

This paper reexamines empirical performance of the monetary exchange rate model with nonlinear dynamics of exchange rate deviation from the monetary fundamentals. First, we apply unit root test of Park and Shintani (2005) to post-Bretton Woods exchange rate data and able to reject the null of unit root deviation from monetary fundamentals against alternative hypothesis of nonlinear stationary process for deutschemark, pound, and Swiss franc. Our empirical results find that exchange rates show high degree of mean-reversion with larger deviation and long periods of overvaluation and undervaluation of dollar. We also find empirical evidence of predictability of the monetary fundamentals at longer horizons.     

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.     

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.     

Should monetary policy respond to asset price misalignments?

This paper analyses the relationship between monetary policy and asset prices using a structural rational expectations open economy model that allows for the effect of asset prices and exchange rates on aggregate demand. We assume that asset prices and exchange rates follow a partial adjustment mechanism whereas they are positively affected by past changes, thus allowing for ‘momentum trading’, while at the same time we allow for reversion towards fundamentals. We then conduct stochastic simulations using two alternative monetary policy rules, inflation-forecast targeting and the standard Taylor rule. The results indicate that, under both rules, interest rate setting that takes into account asset price misalignments leads to lower overall macroeconomic volatility, as measured by the postulated loss function of the central bank.     

Mean reversion in target zones: a re-examination of some ERM exchange rates

The theoretical literature on exchange rate behaviour in target zones predicts that the exchange rate would be mean reverting. This article empirically investigates this theoretical prediction in the case of the German mark bilateral exchange rates. Using a recently developed unit root test, this article provides evidence that is generally negative to the idea of mean reversion. It shows that all bilateral exchange rates under investigation appear to be unit root processes with the exception of the Dutch guilder/German mark rate.     

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.     

Excess volatility of real exchange rates in the EMS: some evidence from structural VARs

This paper argues that the effectiveness of the exchange rate mechanism (ERM) of the European Monetary System (EMS) should be gauged by its impact on the monetary component of real exchange rate variability. Nominal and real shocks are separated using a bivariate structural VAR applied to real exchange rate data of the six original member countries participating in the ERM and a control group consisting of Britain and the United States. The findings suggest that monetary shocks have been an important source of real exchange rate variability and that the ERM has been successful in reducing the incidence of monetary shocks across its member countries prior to the EMS currency crises of 1992–93, while being less successful thereafter.     

SOME EVIDENCE ON MEAN REVERSION IN EX ANTE REAL INTEREST RATES

Ex ante real interest rates and their differentials are tested for mean reversion using quarterly data on three-month treasury bill rates and consumer prices for 12 major industrial countries over the period 1972:l-1993:3. The results are strongly supportive of mean reversion, particularly when less conventional tests are employed. The conclusion that can be derived from the empirical evidence is that goods, capital and foreign exchange markets have become highly integrated in the countries under consideration.     

Generalized long memory and mean reversion of the real exchange rate

Definitive evidence regarding a rapid mean reversion of the real exchange rate is not present when using standard linear methodology, including unit root tests and fractional integration. To consider the robustness of these results, we use an encompassing model, the Gegenbauer AutoRegressive Moving Average (GARMA) model, which nests as special cases the existing linear methods. The GARMA model accommodates a complete notion of persistence and allows shocks to dissipate slowly in a cyclical manner. We find evidence supporting a weak version of purchasing power parity, where equilibrium errors are long memory with strongly persistent cycles. However, this new form of cyclical mean reversion is likely too slow to be economically meaningful. The inability to find a strong equilibrium attractor process, using a very general encompassing linear methodology provides support for the recent models that allow for a nonlinear attraction process and for shifting real exchange rate equilibria.     

Excess Volatility of Exchange Rates with Unobservable Fundamentals

The authors present tests of excess volatility of exchange rates which impose minimal structure on the data and do not commit to a choice of exchange rate "fundamentals." The method builds on existing volatility tests of asset prices, combining them with a procedure that extracts unobservable fundamentals from survey-based exchange rate expectations. The method is applied to data for the three major exchange rates since 1984, and broad evidence is given of excess volatility with respect to the predictions of the canonical asset-pricing model of the exchange rate with rational expectations.     

Modelling the FF/MM rate by threshold cointegration analysis

This paper investigates a sticky-price model of exchange rate determination: extension of Krugman's target zone model with price inertia applied to the French Franc. A novel theoretical argument is considered, Threshold Cointegration, such that the long-run relationship between the parity and its fundamentals is dormant within a certain range of disequilibria but is restored when the system crosses the boundaries. Over the period 1987–1993, nonlinearities in the FF/DM rate, consistent with the credibility of this target zone, were detected by pointing out a band-reversion mechanism. A shock persistence analysis which highlights a nonlinear reversion of the exchange-rate deviation is also implemented.     

Irreversible exit decisions under mean-reverting uncertainty

Although many economic variables of interest exhibit a tendency to revert to long-run levels, mean reverting processes are rarely used in investment and disinvestment models in the literature. Previous work by Sarkar (J Econ Dyn Control 28(2):377–396, 2003), that focuses on irreversible entry decisions, showed that mean reversion has three effects on investment: (a) the “variance effect” (mean reversion reduces the long-run uncertainty and thus brings closer the critical investment level), (b) the “realized price effect” (the lower variance resulting from mean reversion makes it less likely to reach extreme high or low price levels, thereby reducing the likelihood of reaching the investment trigger) and (c) the “risk discounting effect” (mean reversion lowers the required rate of return, which affects both the project value and the value of the real option to invest). Metcalf and Hassett (J Econ Dyn Control 19(8):1471–1488, 1995) and Sarkar (J Econ Dyn Control 28(2):377–396, 2003) showed that (a) and (b) work in opposite directions, essentially canceling each other out, however the effect of (c) depends on parameter values, making the overall effect (a–c) of mean reversion on entry decisions ambiguous and parameter-dependent. In this paper, we show that as far as irreversible exit decisions are concerned, the effect of mean reversion is negative: Mean reversion unambiguously lowers the rate of irreversible disinvestment/exit for reasonable parameter values, since the mean reversion in this case only affects the value of the real option to exit and not the value resulting from (real) option exercise.