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.     

DO REAL INTEREST RATES REALLY CONTAIN A UNIT ROOT? MORE EVIDENCE FROM A BOOTSTRAP COVARIATE UNIT ROOT TEST

This paper re‐examines the empirical finding that international real interest rates usually have a unit root. This conclusion is put forth in Rapach and Weber (2004 ), using the Ng and Perron (2001 ) tests. We use Rudebusch's (1993 ) approach to construct the small sample distributions of the Ng and Perron tests, and calculate their asymptotic sizes, size‐adjusted powers and rejection rates. These numbers show that the lack of power in the Ng and Perron tests might account for the findings of Rapach and Weber (2004 ): that the unit root null cannot be rejected for most OECD countries. Size distortions are mild in the case of Ng and Perron tests for two series, but are serious for the Phillips and Perron Z‐test on inflation rates. We then apply a powerful covariate augmented Dickey–Fuller unit root test to examine the series for which stationarity cannot be determined with the Ng and Perron tests. The bootstrap technique is also used to control possible size distortions. In contrast to the results of Rapach and Weber (2004 ), the bootstrap covariate augmented Dickey–Fuller test yields striking evidence that real interest rates are stationary for 14 of 16 OECD countries, because nominal interest rates are stationary for the 14 countries, while inflation rates are stationary for all countries.     

Reconsidering Real Interest Parity for Traded and Nontraded Goods

The goal of this paper is to examine the hypothesis of real interest rate parity by contrasting real interest rates across traded and nontraded goods under flexible exchange rates. We employ panel unit root tests to investigate the stationarity of real interest rate differentials. In particular, empirical results support the mean‐reverting property of real interest rate differentials for interest rates measured in terms of traded goods.     

Mean-reversion in international real interest rates

This paper examines the mean-reversion property of real interest rates. Many past studies have reported puzzling outcomes of the mean-aversion of real interest rates for a number of countries. In the article, we employ panel unit root tests and carry out half-life estimation based on the bias-corrected bootstrap. These findings of the paper provide strong evidence that, in both major Western and East Asian capital markets (including several emerging ones), real interest rates are mean-reverting. In addition, we find evidence that the degree of mean-reversion of the real interest rates is positively correlated with that of output growth, which is consistent with the implications of standard intertemporal behavior.     

Unit roots and persistence in the nominal interest rate: a confirmatory analysis applied to the OECD

Abstract.  This paper investigates the stochastic properties of long-term and short-term nominal interest rates for the OECD over the post-war era. For that purpose, we employ univariate unit root tests as well as panel unit root and stationarity tests that explicitly allow for cross-sectional dependence. Overall, we find overwhelming evidence that the nominal interest rate contains a unit root, which may be driven by a stochastic common factor. The computation of half-lives through impulse-response functions also points to a high degree of persistence. This has important implications for the cointegration analysis of the Fisher equation, the uncovered interest parity, and the term structure.     

A REVISIT TO THE STATIONARITY OF OECD INFLATION: EVIDENCE FROM PANEL UNIT‐ROOT TESTS AND THE COVARIATE POINT OPTIMAL TEST*

This paper re‐examines the stationarity of inflation rates in 19 Organisation for Economic Cooperation and Development countries with the use of cross‐sectional information. We employ the panel unit‐root tests that allow for cross‐sectional dependency and the covariate point optimal test. These tests have high power in common due to the exploitation of cross‐sectional information, and they can assist mutually to draw a concrete conclusion on inflation dynamics for all series in the panel. Our empirical results show that allowing for cross‐sectional dependency rejects the null hypothesis that all series in the panel have a unit root, implying that there is at least one stationary series in the panel. With the help of the results of the covariate test, we can distinguish the panel into a group of stationary and a group of non‐stationary series. For robustness, the two groups of series are re‐confirmed by the panel tests. Our results reveal evidence of mean reversion in inflation for 15 of 19 countries, which is significantly stronger as compared to that obtained by the state‐of‐the‐art univariate unit‐root tests.     

New tests for stationarity and parity reversion: Evidence on New Zealand real exchange rates

The present paper discusses the stochastic stationarity of New Zealand exchange rates in light of new time series methods and new tests. The question of whether the real exchange rates have a unit root or are mean reverting is set in the general framework of fractionally integrated models. The estimates sustain the claim that New Zealand real exchange series are not stationary. However, it is shown that nonstationarity is compatible with parity reversion in the framework of fractional unit-root models.     

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.     

Testing for a unit root with covariates against nonlinear alternatives

This paper proposes a new procedure for testing the unit root null against stationary but nonlinear alternatives. This test can be viewed as a generalization of the one developed by Kapetanios et al. (2003) (the KSS test) by incorporating stationary covariates. The asymptotic distribution of the test is derived and the asymptotic critical values are tabulated. A set of Monte Carlo simulations show that our test generally achieves large power improvements over the KSS test. An illustrated empirical application indicates that our proposed test is able to unveil more evidence than the KSS test in favor of no unit root of real exchange rates in 15 Asian countries.     

A revisit on real interest rate parity hypothesis – simulation evidence from efficient unit root tests

A set of unit root tests are applied to test the existence of long-run real interest rate parity among the G-10 countries over the period 1971M1 to 2007M2. Rather than trusting the asymptotic distributions, this article uses simulation techniques to establish the small sample distributions of these tests, conditional on the stationary and nonstationary processes. The empirical results indicate that the tests have stable finite-sample sizes and higher size-adjusted powers such that the two estimated processes can be distinguished from each other. Thus, for six of the nine countries, their series are more likely to come from the estimated Autoregressive (AR) stationary process than from the nonstationary process. Noticeably, the testing results are rather different from those using the asymptotic distributions, in which only three countries support the real interest rate parity.     

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.     

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.     

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.     

Testing for unemployment hysteresis in nonlinear heterogeneous panels: International evidence

Nonlinear behavior of unemployment is well documented in the literature, and thus linear unit root tests may not be appropriate in this case. This paper tests for hysteresis of unemployment for 29 OECD countries through the use of a new nonlinear panel unit root test developed by Ucar and Omay (2009). The test examines the joint null hypothesis of linearity and a unit root against the alternative hypothesis of nonlinear stationarity. Large power gains are achieved by both combining cross-sectional information with nonlinearities in the data. In addition, after the unit root null being rejected, we use a sequential panel selection method suggested by Chortareas and Kapetanios (2009) to classify the whole panel into a group of stationary countries and a group of non-stationary countries. The empirical findings show that the nonlinear panel test gives strong evidence in favor of the natural rate hypothesis of unemployment for 23 of 29 OECD countries, in contrast to those obtained by Chang's (2002) linear panel test that 17 countries display evidence of stationary unemployment.     

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.     

Budget deficits,short-term real interest rates and the specification of expected inflation: an empirical investigation

The purpose of this paper is to illustrate whether empirical estimates of the effects of budget deficits on short-term real interest rates are sensitive to the choice of the expected inflation variable. Survey data on expected inflation and the rational expectations method described by Mishkin (1981) are used to construct two measures of the short-term real interest rate. Results for two previous studies on this deficit-interest rate relationship are re-estimated using these measures of expected inflation and the interest rate variables. Additional results reported in this paper further indicate that empirical estimates of the interest rate effects of budget deficits are sensitive to the choice of the expected inflation variable. In addition to the choice of the inflation variable, a number of other robustness tests are included. We are able to conclude that (1) increases in budget deficits do not generally raise short-term real interest rates and (2) short-term real interest rates are not independent of the expected inflation variable.

The rate of interest is always based upon expectation, however little this may be justified by realization. Man makes his guess of the future and stakes his action upon it … Our present acts must be controlled by the future, not as it actually is, but as it appears to us through the veil of chance (Fisher, 1907, p. 213).     

Smooth transition trends and labor force participation rates in the United States

This paper employs smooth transition trend models to investigate the long-run time series behavior of quarterly US labor force participation rates. In particular, we examine whether long-run growth in labor force participation rates can be modeled by smooth transitions between states rather than as abrupt mean level changes or as a stochastic trend. Smooth transitions permit for non-instantaneous adjustment of individual workers to changes associated with economic events or general labor market conditions. We employ unit root testing procedures with alternatives characterized by stationary fluctuations around one or two smooth transitions in linear trend. We examine labor force participation rates by gender- and age-specific groups. The results indicate that all female and most male participation series are better characterized as stationary processes that undergo transitional deterministics.     

Nonlinear Mean-Reversion in Real Exchange Rates: Toward a Solution To the Purchasing Power Parity Puzzles

We fit nonlinearly mean-reverting models to real dollar exchange rates over the post-Bretton Woods period, consistent with a theoretical literature on transactions costs in international arbitrage. The half lives of real exchange rate shocks, calculated through Monte Carlo integration, imply faster adjustment speeds than hitherto recorded. Monte Carlo simulations reconcile our results with the large empirical literature on unit roots in real exchange rates by showing that when the real exchange rate is nonlinearly mean reverting, standard univariate unit root tests have low power, while multivariate tests have much higher power to reject a false null hypothesis.     

FURTHER EVIDENCE ON REAL INTEREST RATE EQUALIZATION: PANEL INFORMATION,NON‐LINEARITIES AND STRUCTURAL CHANGES

Previous studies applying traditional unit root tests generally have difficulty providing widespread evidence supporting the real interest rate parity hypothesis (RIPH). This paper aims to analyse the empirical fulfilment of RIPH for 17 OECD countries by employing many recently developed unit root tests. Power of the tests is raised by taking different approaches, such as using cross‐sectional information, accounting for non‐linear adjustment towards the equilibrium and allowing for structural changes. The combined results of the tests using panel information show that broad evidence in favour of RIPH prevails for 13 of the 17 countries. By contrast, univariate tests fail to make widespread rejections of the unit‐root hypothesis. Our evidence reveals a high degree of market integration for developed countries, and the effect of monetary policies as a stabilization tool might be limited at least in the long run.     

Mean Reversion of Short‐run Interest Rates in Emerging Countries*

In this paper we examine the stochastic behavior of short‐run interest rates in several emerging countries using fractional integration techniques. We allow for a much richer flexibility in the dynamic behavior of the series than the classical representations based on I(0) or I(1) processes. It appears that for Singapore and Thailand nominal interest rates are mean‐reverting, whereas for Mexico, Malaysia, the Philippines, and Korea, the presence of a unit‐root test depends on the assumptions regarding the residuals’ autocorrelation. The results also suggest that uncovered interest parity (UIP) can only hold for two emerging countries. For the other countries, the stabilization policies in the aftermath of the currency crises have led to the rejection of the UIP hypothesis.