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.     

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.     

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.     

Spurious regression: A higher-order problem

This paper investigates solving the spurious regression problem using an autocorrelation correction. It is shown that if the relevant data generation processes contain higher-order terms, this solution is not as effective as in the first-order case.     

Hysteresis in unemployment for 17 OECD countries: Stationary test with a Fourier function

In this empirical study, we apply stationary test with a Fourier function proposed by Becker et al. (2006) to re-examine the hysteresis hypothesis in unemployment for 17 OECD countries over the 1960 to 2009 period. The hysteresis in unemployment is confirmed for most of these 17 OECD countries, with the exception of Australia, Canada, Finland, France, Sweden and the USA, when Becker et al.'s (2006) stationary test with a Fourier function is conducted.     

The FMLS-based CUSUM statistic for testing the null of smooth time-varying cointegration in the presence of a structural break

In this paper we extend the FMLS-based CUSUM cointegration test (Xiao and Phillips, 2002) for testing the smooth time-varying cointegration null hypothesis. For this purpose we use Chebyshev time polynomials to specify time-varying coefficients under the null. We derive the limiting distribution of the statistic, which is pivotal with the order of the Chebyshev time polynomials, and we provide the critical values to conduct the proposed test.     

Fourier nonlinear quantile unit root test and PPP in Africa

We test the PPP hypothesis in 29 African countries using a newly developed nonlinear Quantile unit root test with a Fourier function which accounts for smooth breaks. Simulation indicates that the proposed new test has higher power than the conventional Quantile unit root test as proposed by Koneker and Xiao (2004). Our empirical results provide support for the PPP hypothesis in 21 out of 29 African countries, a unique discovery using their real effective exchange rates. It appears that incorporating Fourier function to nonlinear Quantile unit root test gets us closer and closer to solving the PPP puzzle in Africa.     

Flexible Fourier unit root test of unemployment for PIIGS countries

In this empirical study, we apply the flexible Fourier unit root test proposed by Enders and Lee (2012) to re-examine the hysteresis hypothesis of unemployment for PIIGS (Portugal, Ireland, Italy, Greece, and Spain) countries over the period from 1960 to 2011. We find that the Fourier unit root test has greater power than a linear method if the true data generating process of unemployment is a stationarity, non-linear process of an unknown form with structural change. The hysteresis in unemployment is confirmed for all PIIGS countries, with the exception of Portugal and Spain, when the Fourier unit root test is conducted.     

Exchange rate regime verification: An alternative method of testing for regime changes

This work proposes a change in persistence test for identifying de facto exchange rate regime changes. The results from 25 African countries show that this approach is able to identify some regime changes not captured by existing methods.     

To Go or Not to Go: Emigration from Germany

Abstract. This study analyses the qualitative aspects of emigration from Germany, taking account of economic and non-economic reasons. The reported willingness to emigrate from Germany in the German Socio-Economic Panel (GSOEP) is explained for men and women by three groups of variables: individual characteristics, household characteristics and regional characteristics. It transpires that the educational background and West German residency positively affect the willingness to emigrate, whereas German nationality, age and the family situation are mostly negatively correlated with it.     

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.     

Dynamic Costs of the Draft

Abstract. We propose a dynamic general‐equilibrium model with human capital accumulation to evaluate the economic consequences of compulsory services (such as military draft or social work). Our analysis identifies a so far ignored dynamic cost arising from distortions in time allocation over the life cycle. We provide conservative estimates for the excess burden that arises when the government relies on forced labor rather than on income taxation to finance public expenditures. Our results suggest that eliminating the draft could produce considerable dynamic gains, both in terms of GDP and lifetime utility.     

Does seasonality change over the business cycle? An investigation using monthly industrial production series

This paper examines the proposition that the business cycle affects seasonality in industrial production, with output being switched to the traditionally low production summer months when recent (annual) growth has been strong. This is investigated through the use of a restricted threshold autoregressive model for the monthly growth rate in a total of 74 industries in 16 OECD countries. Approximately one-third of the series exhibit significant nonlinearity, with this nonlinearity predominantly associated with changes in the seasonal pattern. Estimates show that the summer slowdown in many European countries is substantially reduced in the regime of higher recent growth.     

Multi-horizon inflation forecasts using disaggregated data

In this paper we use multi-horizon evaluation techniques to produce monthly inflation forecasts for up to twelve months ahead. The forecasts are based on individual seasonal time series models that consider both, deterministic and stochastic seasonality, and on disaggregated Consumer Price Index (CPI) data. After selecting the best forecasting model for each index, we compare the individual forecasts to forecasts produced using two methods that aggregate hierarchical time series, the bottom-up method and an optimal combination approach. Applying these techniques to 16 indices of the Mexican CPI, we find that the best forecasts for headline inflation are able to compete with those taken from surveys of experts.     

Inflation targeting in Latin America: Empirical analysis using GARCH models

This paper studies inflation dynamics in eight Latin American countries, some of which have adopted formal inflation targets (IT) as their monetary policy frameworks. We analyze the possible benefits associated with IT, not only in terms of inflation level and volatility, but also regarding other nonlinear characteristics of these series, such as volatility persistence or the fulfillment of the Friedman hypothesis. To describe inflation dynamics we use an unobserved components model, where each component can follow a GARCH type process. Once we estimate the model, the main findings of the empirical exercise confirm the favorable performance of IT.     

Estimates of a labour supply function using alternative measures of hours of work

Depending on data source, estimates of hours of work give widely different results both as to level and change. In this paper three alternative measures of hours worked are used to estimate a simple labour supply function to investigate if the estimated wage rate and income effects are data dependent as well. The measures used include those from time-use surveys and those from regular surveys. The latter are based on the responses to a question about normal weekly hours of market work. The results suggest that the estimates of the wage rate effects become much smaller when measures of normal hours are used compared to data collected for a well-defined time period close to the date of interview, such as time-use data. The income effects appear less sensitive to the choice of data.     

Testing the unit root hypothesis against TAR nonlinearity using STAR-based tests

This paper investigates the finite-sample power of STAR-based unit root tests when the data generation process is a globally stationary three-regime TAR model. Unit root tests are proposed derived from STAR models that nest TAR models.     

Estimating GARCH volatility in the presence of outliers

GARCH volatilities depend on the unconditional variance, which is a non-linear function of the parameters. Consequently, they can have larger biases than estimated parameters. Using robust methods to estimate both parameters and volatilities is shown to outperform Maximum Likelihood procedures.