Quantile nonlinear unit root test with covariates and an application to the PPP hypothesis

In this article, we employ the methods initiated by Hansen (1995) to develop new quantile nonlinear unit root tests with covariates. The limiting distributions of our proposed tests are derived, which are dependent on nuisance parameter reflecting the correlation between the equation error and the covariates. To deal with this inferential difficulty, two alternative procedures based on either consistent estimate of the nuisance parameter or bootstrap implementation of the test are proposed. Monte Carlo simulations show that the proposed tests perform very well in finite samples and large power gains can be achieved by including correlated covariates in the testing equation. The proposed tests are applied to the PPP hypothesis. The empirical results indicate that the real exchange rates are not constant unit root processes.     

Asymptotic behaviour of tests for a unit root against an explosive alternative

We compare the asymptotic local power of upper-tail unit root tests against an explosive alternative based on ordinary least squares (OLS) and quasi-differenced (QD) demeaning/detrending. We find that under an asymptotically negligible initialisation, the QD-based tests are near asymptotically efficient and generally offer superior power to OLS-based approaches; however, the power gains are much more modest than in the lower-tail testing context. We also find that asymptotically non-negligible initial conditions do not affect the power ranking in the same way as they do for lower-tail tests, with the QD-based tests retaining a power advantage in such cases.     

Markov-switching models and the unit root hypothesis in real US GDP

I find that real US GDP is better characterized as a trend stationary Markov-switching process than as having a (regime-dependent) unit root. I examine the effects of both assumptions on the analysis of business cycle features and their implications for the persistence of the dynamic response of output to a random disturbance.     

Per capita output convergence across Asian countries: Evidence from covariate unit root test with an endogenous structural break

This study investigates long-run convergence of per capita output across ten Asian countries over 1960 to 2014 by taking advantage of possible economic growth determinants, which may be responsible for setting Asian countries on a long-term steady-state growth path. We simultaneously examine the presence of output convergence in the region, as well as the statistical significance of these economic growth determinants, by using a unit root test with a stationary covariate. In addition, the study allows for the presence of endogenous structural changes in the time series under investigation in order to capture sharp drops in per capita outputs, which may be brought about by influential economic events, such as serious economic slumps in domestic economies or the global financial crises in 1997–98 and 2008–09. The limiting distribution of the covariate unit root test that permits structural breaks is also derived. The results show significant evidence to support the convergence hypothesis. In particular, asymptotically absolute convergence holds among Hong Kong, Korea, Singapore, and Taiwan. In addition, Thailand shows a convergence tendency in terms of asymptotically relative convergence toward Singapore. Malaysia, Indonesia, and India also turn out to converge toward Hong Kong in an asymptotically relative sense. Certain potential growth determinants, such as the trade/GDP ratio, inflation rate, government expenditure/GDP ratio, and quality of human capital, may help these countries achieve and maintain the long-run convergence process toward the reference countries in the region.     

A fractionally integrated exponential STAR model applied to the US real effective exchange rate

The aim of this paper is to study the dynamics of the US real effective exchange rate by capturing non-linearity and long-memory features. In this context, we use the family of fractionally integrated STAR (FISTAR) models proposed by van Dijk et al. (van Dijk, D., Franses, P.H., and Paap, R., 2002. A non-linear longmemory model with an application to US unemployment. Journal of Econometrics 110, 135–165.) in the case when the transition function is an exponential function and we develop an estimation procedure. Indeed, these models can take into account processes characterized by several distinct dynamic regimes and persistence phenomena.     

On testing for nonlinearity in multivariate time series

This paper considers a multivariate extension of the test for neglected nonlinearity proposed by Tsay (1986) that uses principal components to overcome the problem of dimensionality that is common with tests of this type. Monte Carlo experiments reveal that the modified multivariate test provides a significant dimensional reduction without suffering from any systematic level distortion or power loss, and is more powerful than univariate nonlinearity tests.     

A Pearson's test for symmetry with an application to the Spanish business cycle

In this paper, we look for asymmetries in the Spanish business cycle. To that end, we firstly propose an easy nonparametric testing procedure to test for symmetry based on a Pearson's chi-squared statistic, which we call P-test. Then, we test for two popular forms of asymmetry, deepness and steepness, using a battery of nonparametric tests. In addition, we analyse possible complementarities between the tests used in this paper, and we compute p-value adjustments for multiple tests.     

A simple spatial dependence test robust to local and distributional misspecifications

In this paper, we derive a class of modified score tests robust to local and distributional misspecifications for testing spatial error autocorrelation and spatial lag dependence. The proposed tests are general enough to include several popular tests for the spatial dependence as special cases. Moreover, we show that the popular test statistics proposed by Burridge (1980) and Anselin et al. (1996) are robust to distributional misspecification although they are derived under normality assumption.     

A simple and effective misspecification test for the double-hurdle model

The commonly-used version of the double-hurdle model rests on a rather restrictive set of statistical assumptions, which are very seldom tested by practitioners, mainly because of the lack of a standard procedure for doing so, although violation of such assumptions can lead to serious modelling flaws. We propose here a bootstrap-corrected conditional moment portmanteau test which is simple to implement and has good size and power properties.     

Monetary shocks,exchange rates and trade balances: Evidence from inflation targeting countries

This paper investigates the relationship among monetary policy shocks, exchange rates and trade balances in five Inflation Targeting Countries (ITCs). The investigation is based on Structural Vector Error Correction Models (SVECMs) with long run and short run restrictions. The findings reveal that a contractionary monetary policy shock leads to a decrease in price level, a decrease in output, an appreciation in exchange rate, and an improvement in trade balance in the very short run. Our findings contradict the findings of price, output, exchange rate and trade puzzles that have been found in many empirical studies. Furthermore they are consistent with the theoretical expectations regarding the effect of a contractionary policy. The only long run restriction that we imposed on our models is that money does not affect real macroeconomic variables in the long run, which is consistent with both Keynesian and monetarist approaches.     

Accounting for human capital externalities with an application to the Nordic countries

Externalities caused by human capital accumulation have taken up considerable space in theoretical work on economic growth. However, less attention has been paid to this externality in traditional growth accounting exercises. This paper takes up the issue of growth accounting, suggesting a framework for quantifying human-capital externalities and illustrating it empirically using data from the five Nordic countries. Four sources of growth are identified, i.e. capital accumulation, labor force growth, and total factor productivity growth (TFP), where the traditional TFP measure is split into a part explained by human-capital formation and an unexplained part. By doing this I am able to attribute between 12 per cent and 33 per cent of growth in the Nordic countries to human capital investment.     

A simple panel stationarity test in the presence of serial correlation and a common factor

This paper develops a simple test à la Pesaran (2007) for the null hypothesis of stationarity in heterogeneous panel data with cross-sectional dependence in the form of a common factor in the disturbance. We also allow for serial correlation.     

Nonlinearity in real exchange rates: an approach with disaggregated data and a new linearity test

Employing disaggregated real exchange rates from nine European counties in 16 goods categories, we assess in this study the nonlinearity in the real exchange rates. Surprisingly, we find evidence for nonlinearity in only four (10) out of 143 series with the linearity test proposed by Harvey et al. (2008 Harvey, D. I., Leybourne, S. J. and Xiao, B. 2008. A powerful test for linearity when the order of integration is unknown. Studies in Nonlinear Dynamics and Econometrics, 12 Art 8[Web of Science ®] , [Google Scholar]) at the 5% (10%) significance level. This result differs greatly from those of Juvenal and Taylor (2008 Juvenal, L. and Taylor, M. P. 2008. Threshold adjustment of deviations from the law of one price. Studies in Nonlinear Dynamics and Econometrics, 12 Art 8[Web of Science ®] , [Google Scholar]), Imbs et al. (2003 Imbs, J., Mumtaz, H., Raven, M. O. and Rey, H. 2003. Nonlinearities and real exchange rate dynamics. Journal of the European Economic Association, 1: 639–49. [Crossref] , [Google Scholar]), Sarno et al. (2004 Sarno, L., Taylor, M. P. and Chowdhury, I. 2004. Nonlinear dynamics in deviations from the law of one price: a broad-based empirical study. Journal of International Money and Finance, 23: 1–25. [Crossref], [Web of Science ®] , [Google Scholar]) and Berka (2009 Berka, M. 2009. “Non-linear adjustment in law of one price deviations and physical characteristic of good”. In Review of International Economics Vol. 17, 51–73.  [Google Scholar]), who report ample evidence for nonlinearity for the same or similarly disaggregated real exchange rate datasets.     

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.     

Some cautions on the use of nonlinear panel unit root tests: Evidence from a modified series-specific non-linear panel unit-root test

The purpose of this paper is to examine the relevance of applying nonlinear panel unit root test to examine the non-linear mean reversion behaviors of real exchange rates. We find that nonlinear panel unit root test may achieve lower power performance as compared to its alternative of linear panel unit test when the data generating process does not contain significant non-linear components. This finding post cautions to researchers in modeling and testing real exchanges behavior. We also develop a modified series-specific nonlinear panel unit root test and find evidence in favor of purchasing power parity hypothesis for China's four ASEAN trading partners in the period of February 1997 to August 2009.     

The persistence in real exchange rate: Evidence from East Asian countries

In this article, we examine the degree of persistence in monthly real exchange rate of six East Asian countries in relation to their two major trading partners, the United States and Japan, to study the validity of PPP for the 1976:01–2009:03 period. To investigate the persistency in real exchange rate series, we use sum of the autoregressive (AR) coefficients and the confidence interval for it using grid-bootstrap procedure recently developed by Hansen (1999). We have two findings: first, we find evidence for high persistency in real exchange rate in terms of the Japanese yen for five countries and for four countries in terms of the US dollar the for the full and pre-crisis sample periods. Second, for the post-crisis period, the presence of low persistency in real exchange rate supports PPP for three countries in terms of the Japanese yen and five countries in terms of the US dollar. These findings indicate that real exchange rate series of five East Asian countries are mean-revert based on their exchange rate policies and East Asian countries can form a currency union.     

A risk-driven approach to exchange rate modelling

The paper presents a new approach to exchange rate modelling that augments the CHEER model with a sovereign credit default risk as perceived by financial investors making their decisions. In the cointegrated VAR system with nine variables comprised of the short- and long-term interest rates in Poland and the euro area, inflation rates, CDS indices and the zloty/euro exchange rate, four long-run relationships were found. Two of them link term spreads with inflation rates, the third one describes the exchange rate and the fourth one explains the inflation rate in Poland. Transmission of shocks was analysed by common stochastic trends. The estimation results were used to calculate the zloty/euro equilibrium exchange rate.     

Panel LM unit root tests with level and trend shifts

This paper considers a Lagrange multiplier (LM) based panel unit root test that allows for heterogeneous structural breaks in both the intercepts and slopes of a series. We note that many popular time series variables are likely to exhibit changing means and/or trends over time. Given that the usual tests will depend on the nuisance parameters indicating the locations of the trend breaks, we adopt a transformation procedure that makes our new panel unit root tests invariant to the nuisance parameters. To illustrate the importance of the power gain provided by our test, we examine the convergence hypothesis using relative ratios of per capita health care expenditures in 20 OECD countries. Our results provide evidence that the convergence hypothesis is supported.     

Testing for efficiency in selected developing foreign exchange markets: An equilibrium-based approach

This paper proposes an alternative way of testing FOREX efficiency for developing countries. The FOREX market will be efficient if fully reflects all available information. If this holds, the actual exchange rate will not deviate significantly from its equilibrium rate. Moreover, the spot rate should deviate from its equilibrium rate by only transitory components (i.e. it should follow a white noise process). This test is applied to three Central and Eastern European Countries — members of the EU. Considering an LSTAR model we find no evidence of nonlinear adjustment in the misalignment series. So, linear unit root tests imply that the Poland/Euro FOREX market is efficient, the Czech/Euro FOREX market is not, while the Slovak/Euro FOREX market is quasi-efficient.     

Imputing rent in consumption measures,with an application to consumption poverty in Canada, 1997–2009

We consider two econometric problems in the measurement of poverty, both relating to rent imputation. First, we account for quality differences correlated with selection into owner‐occupied versus rental tenure. This correction increases estimated household consumption by 5% over uncorrected estimates and decreases estimated poverty rates quite dramatically. Second, we propose that measurement error induced by the imputation be corrected by imputing a consumption distribution, rather than a consumption level, for each household. This correction increases estimated poverty rates slightly. We use our methods to measure consumption poverty in Canada, and find that the imputation strategy used influences the patterns observed. For example, measured poverty among the elderly barely declines when one uses our methods, in contrast to the almost 6 percentage point reduction we find using traditional methods. In our assessment of the over‐time evolution of consumption poverty, we find that substantial progress has been made on overall poverty and on child poverty, but that poverty among the elderly hardly changed.