Testing of unit roots and other fractionally integrated hypotheses in the presence of structural breaks

Tests of unit roots and other nonstationary hypotheses that were proposed by Robinson (1994) are applied in this article to the Nelson and Plosser's (1982) series. The tests can be expressed in a way allowing for structural breaks under both the null and the alternative hypotheses. When applying the tests to the same dataset as in Perron (1989), we observe that our results might be consistent with those in Perron (1989) when testing the nulls of trend-stationarity or a unit-root. However, we also observe that fractionally integrated hypotheses may be plausible alternatives in the context of structural breaks at a known period of time. Final version received: August 2000/Final version accepted: August 2001 RID="*" ID="*"  The author gratefully acknowledges the financial support from the European TMR grant No. ERBFMRX-CT-98-0213. Comments of two anonymous referees are also acknowledged.     

Testing for panel unit roots in the presence of spatial dependency

In this article, the size and power properties of the Common-factor Im, Pesaran and Shin (CIPS), Wald (W), Likelihood Ratio (LR) and Lagrange Multiplier (LM) tests are investigated when the error term follows a spatial error model. In this study, the results from the Monte Carlo simulations, first, show that the CIPS test over-estimates the nominal size. Second, the simulation results show that the empirical size of the W test approaches the nominal size quickly, while the LR and LM tests underestimate the null hypothesis in both small and moderate sample sizes. Finally, the results also show that even though the LM and LR tests under-reject the true-null hypothesis they have higher power than the W test.     

The Polish exchange rate system: A unit root and cointegration analysis

In October 1991 Poland has established a crawling peg regime in which the zloty is tied to a currency basket and devalued with a monthly rate of crawl. If the monetary authorities are successful in defending the crawling peg the basket rate measured in Polish zloty is supposed to be stationary. Furthermore, a stable long-run relationship between the zloty-U.S. dollar rate and the basket's value expressed in U.S. dollar is expected to exist. The results of the unit root and cointegration analysis indicate that the monetary authorities have been able to defend the crawling peg for the sample periods under study, although it seems that not all requirements of the exchange rate regime have been met. The foreign exchange markets, however, have not supported the relationships derived from the crawling peg system after the introduction of the free floating system in April 2000.The final version of this paper has been prepared while I was a Jean Monnet Fellow at the European University Institute. I would like to thank the EUI for the award of the Fellowship and its hospitality. Moreover, I am grateful to Helmut Lütkepohl, Anja Schulz, Ralf Brüggemann, and two anonymous referees for many helpful comments and suggestions. I also thank the Deutsche Forschungsgemeinschaft, SFB 373, for financial support.     

A wavelet-based panel unit-root test in the presence of an unknown structural break and cross-sectional dependency,with an application of purchasing power parity theory in developing countries

This article introduces two different non-parametric wavelet-based panel unit-root tests in the presence of unknown structural breaks and cross-sectional dependencies in the data. These tests are compared with a previously suggested non-parametric wavelet test, the parameteric Im-Pesaran and Shin (IPS) test and a Wald type of test. The results from the Monte Carlo simulations clearly show that the new wavelet-ratio tests are superior to the traditional tests both in terms of size and power in panel unit-root tests because of its robustness to cross-section dependency and structural breaks. Based on an empirical Central American panel application, we can, in contrast to previous research (where bias due to structural breaks is simply disregarded), find strong, clear-cut support for purchasing power parity (PPP) in this developing region.     

Understanding the cell phone effect on vehicle fatalities: a Bayesian view

This article examines the potential effect of various factors on motor vehicle fatality rates using a rich set of panel data and classical regression analysis combined with Bayesian Extreme Bounds Analysis (EBA), Bayesian Model Averaging (BMA) and Stochastic Search Variable Selection (SSVS) procedures. The variables examined in the models include traditional motor vehicle and socioeconomic factors. In addition, the models address the effects of cell phone usage on such accidents. The use of both classical and Bayesian techniques diminish the model and parameter uncertainties which afflict more conventional modelling methods which rely on only one of the two methods.     

Examining the link between crime and unemployment: a time-series analysis for Canada

We use national and regional Canadian data to analyse the relationship between economic activity (as reflected by the unemployment rate) and crime rates. Given potential aggregation bias, we disaggregate the crime data and look at the relationship between six different types of crimes rates and unemployment rate; we also disaggregate the data by region. We employ an error correction model in our analysis to test for short-run and long-run dynamics. We find no evidence of long-run relationship between crime and unemployment, when we look at both disaggregation by type of crime and disaggregation by region. Lack of evidence of a long-run relationship indicates we have no evidence of the motivation hypothesis. For selected types of property crimes, we find some evidence of a significant negative short-run relationship between crime and unemployment, lending support to the opportunity hypothesis. Inclusion of control variables in the panel analysis does not alter the findings, qualitatively or quantitatively.     

Long-run determinants of pollution: A robustness analysis

This paper examines how robust economic, political, and demographic variables are related to water and air pollution. Employing Bayesian Averaging of Classical Estimates (BACE) for a cross section of 47 countries, 34 variables and 3 proxies for air and water pollution over a period from 1980 to 2000 we confirm the environmental Kuznets curve hypothesis and highlight the relevance of variables that are not directly related to production.     

Re-examination of convergence hypothesis among Indian states in panel stationarity testing framework with structural breaks

This article examines the conditional income convergence hypothesis for 17 major states in India for the period of 1960–2012. Univariate stationarity tests without structural breaks provide evidence against the convergence hypothesis. However, when two or more structural breaks are applied in per capita income series, the incomes of around 11–13 states are found to stochastically converge to the national average. This finding supports the convergence hypothesis for the panel as a whole after accounting for two data features, cross-sectional dependence and structural breaks in incomes, using a unified panel stationarity testing framework.     

The intertemporal relation between government revenue and expenditure in the United Kingdom, 1750 to 2004

We examine the intertemporal relation between government revenue and expenditure in the UK during 1750 to 2004. We pay particular attention to long run trends by applying a battery of unit root and cointegration techniques to the data, and we use a modified Granger causality test on data spans organized around structural breaks in the series. The results suggest that, allowing for structural breaks, UK real revenue and spending are I(1) series and cointegrated and that Granger causality runs from government spending to revenue. As such, the ‘spend-tax’ hypothesis appears to best characterize the long run intertemporal relation between government revenue and spending in the UK.     

An analysis of East Asian currency area: Bayesian dynamic factor model approach

There has recently been an increasing interest in the establishment of a common currency area in East Asia in the aftermath of the East Asian financial crisis. In this article I examine the desirability and feasibility of forming a currency area in the region by checking the symmetry of shocks as an important criterion of the theory of Optimum Currency Area. I employ a dynamic factor model to decompose aggregate output into world, regional and country‐specific components and estimate the model using a Gibbs sampling simulation. Persistent properties of those components are examined and variance decomposition analysis is performed to investigate the role of each component in output variance. The European Monetary Union, with the successful launch of the euro, is the natural benchmark for comparison. Based on variance analysis, it is found that East Asian countries, on average, are less plausible candidates for a currency area than European counterparts. However, a subgroup of countries in East Asia is as qualified as those in Europe. Given the ongoing integration in East Asia, it is not premature to prepare for such a currency area in this region.     

Modeling probabilities of patent oppositions in a Bayesian semiparametric regression framework

Previous econometric analyses of patent data rely on regression methods using purely parametric forms of the predictor for modeling the dependence of the response. These approaches lack the capability of identifying potential non-linear relationships between dependent and independent variables. In this paper, we present a Bayesian semiparametric approach making use of Markov Chain Monte Carlo (MCMC) simulation techniques which is able to capture these non-linearities. Using this methodology we reanalyze the determinants of patent oppositions in Europe for biotechnology/pharmaceutical and semiconductor/computer software patents. Our semiparametric specification clearly finds considerable non-linearities in the effect of various metrical covariates which has been not been discussed previously. Further, a formal model validation based on ROC-methodology which splits the data in a training and a validation data set shows a significant improvement of the explanatory and the predictive power of our approach compared to purely parametric specifications.

Comparing new Keynesian models in the Euro area: a Bayesian approach

This paper estimates and compares four versions of the sticky price New Keynesian model for the Euro area using a Bayesian approach. We find that the average duration of price contracts is between two and four quarters, while the average duration of wage contracts is estimated to be below two quarters. Both mechanisms of price and wage indexation are not important when autocorrelated price markup shocks are introduced in the model. These results are in stark contrast to Smets and Wouters (2003): when we use their priors, our estimated posterior distributions are similar to theirs, but the models’ fit to the data is worse. We are thankful to the Econometric Modelling Unit at the European Central Bank for providing us with the Euro area data. We also thank two anonymous referees for helpful suggestions. The views expressed in this paper are those of the authors and do not necessarily reflect the views of Caixa d’Estalvis i Pensions de Barcelona (“la Caixa”).     

我国结构性失业原因与对策研究

针对当前全球性金融危机带来的巨大劳动力市场冲击,分析了传统结构性失业的基本概念、典型特征以及在我国的突出表现、一般和特殊原因,提出政府现今及未来较长一段时间实现扩大内需、促进发展、扶持民生、确保就业的目标,提出重点加强职业技术培训,着力提高劳动力整体素质,积极改善宏观经济环境,稳定社会和人民群众生活,避免金融危机向经济危机演化,尽快解决结构性失业等一整套对策、建议。     

Comparisons of robust tests for shifts in trend with an application to trend deviations of real exchange rates in the long run

We study the finite sample properties of tests for structural changes in the trend function of a time series that do not require knowledge of the degree of persistence in the noise component. The tests of interest are the quasi-Feasible Generalized Least Squares (FGLS) procedure by Perron and Yabu (2009b Perron, P and Yabu, T. 2009b. Testing for shifts in trend with an integrated or stationary noise component. Journal of Business and Economic Statistics, 27: 369–96. [Taylor &; Francis Online], [Web of Science ®] , [Google Scholar]) and the weighted average of the regression t-statistics by Harvey et al. (2009 Harvey, DI, Leybourne, SJ and Taylor, AMR. 2009. Simple, robust, and powerful tests of the breaking trend hypothesis. Econometric Theory, 25: 995–1029. [Crossref], [Web of Science ®] , [Google Scholar]), both of which have the same limit distribution whether the noise component is stationary or has a unit-root. We analyse the finite sample size and power properties of these tests under a variety of Data-Generating Processes (DGPs). The results show that the Perron–Yabu test has greater power overall. With respect to the size, the Harvey–Leybourne–Taylor test exhibits larger size distortions unless a moving-average component is present. Using the Perron and Yabu procedure to test for structural changes in the trend function of long-run real exchange rates with respect to the US dollar indicates that for 17 out of 19 countries, the series have experienced a shift in trend since the late nineteenth century.     

Assessing the predictive power of financial spreads in the euro area: does parameters instability matter?

In the empirical literature there is wide consensus that financial spreads cannot constitute a broadly based assessment on future output growth and inflation because the bivariate estimated regressions are not stable over time and lead to relatively poor out-of-sample forecasting performance (e.g. J Econ Liter 41:788–829, 2003). This conclusion arised for the USA, as well as for several European countries. In this paper we check whether the marginal predictive content of some financial spreads (the slope of the yield curve, the reverse yield gap and the credit spread) for macroeconomic forecasting in the euro area can be recovered using techniques taking into account potential parameters instability. We set up a quarterly Bayesian vector autoregression model with time-varying coefficients, comprising both target variables, as well as other monetary policy indicators, to serve as a benchmark. Then, the properties of the spreads as leading indicators are assessed by augmenting this benchmark BVAR with the spreads, one at a time. We find time variation of the coefficients to be a relevant issue in our model, especially for forecasting output growth, but financial spreads continue to have no or negligible marginal predictive content for both output growth and inflation. Overall, our results confirm that there is no ready-to-use financial spread that can replace an encompassing multivariate model for the prediction of target variables in the euro area.      

事业单位会计信息失真的研究

事业单位会计工作可以定义为,反映事业单位的发展情况和提供公共产品、服务的成本效益情况,向社会提供事业单位的财务状况,向资金捐赠者履行受托责任的情况以及提供其他有用信息。从事业单位和事业单位会计的概念入手,深入探讨了目前我国事业单位会计信息失真的问题,提出了解决问题的方法和建议。     

中国参与ICP的理论基础与实证检验——基于人民币购买力平价理论的协整分析

我国将于2012年通过购买力平价换算GDP参与国际比较项目(ICP),人民币购买力平价在长期内是否成立是我国能否顺利参与这一项目的关键。在中外购买力平价(PPP)实证研究的基础上,选择三变量模型,对1950～2009年间人民币汇率及其中美CPI年度数据进行实证检验。旨在为我国参与ICP提供理论上的支持。     

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.     

On the pooling of cross-sectional and time-series data in the presence of heteroskedasticity

We analyze the effect of heteroskedasticity on log-linear aggregation, and its implications for the pooling of cross-section and aggregate time series data. An empirical analysis of food consumption, based on US family budget survey and aggregate time series data, illustrates.     

Drift in the relative price of primary commodities: a case where we care about unit roots

The evidence for the Prebisch-Singer hypothesis, of a downward drift over time in the relative price of primary commodities, is considered. The apparent strength of that evidence appears to depend, to a substantial degree, on whether the time series of relative prices is assumed to be trend stationary or integrated of order one. Moreover, the usual econometric tests are relatively uninformative on this question. These conclusions emerge whether or not a structural break in the series is permitted.