Inequality convergence revisited: Evidence from stationarity panel tests with breaks and cross correlation

This paper empirically examines whether there exists stochastic convergence of income inequality among 48 contiguous states within the US over the 1916–2005 period. For that purpose, we employ the recently developed panel stationarity test of Carrion-i-Silvestre, Del Barrio-Castro and López-Bazo (2005), which assumes a highly flexible trend function by incorporating an unknown number of structural breaks. In addition, the issues of cross-sectional dependence as well as control for finite-sample bias are accommodated through bootstrap methods. Overall, for the US case, our analysis provides strong evidence in support of the hypothesis of inter-state inequality convergence. Moreover, the results are robust to alternative inequality measures applied, different notions of stochastic convergence defined, and alternative panel stationary test employed.     

Are OECD consumption–income ratios stationary after all?

This paper investigates the stochastic properties of the consumption–income ratio for a sample of 23 OECD countries over the period 1960–2005. For that purpose, we employ a battery of recently developed panel unit root and stationarity tests. Our findings from panel unit root tests which do not control for structural breaks appear in line with those from previous studies since they are clearly supportive of the unit root hypothesis. In stark contrast stand the results obtained from the application of a panel stationarity test with multiple breaks, which support the existence of regime-wise stationarity in OECD consumption–income ratios once we control for cross-sectional dependence through bootstrap methods. These findings are reinforced by the median-unbiased estimates of half-lives obtained from impulse-response functions which are found to be finite for the 23 OECD countries.     

Convergence in Sub-Saharan Africa: a nonstationary panel data approach

Given the development of time series econometrics and nonstationary data analysis, St. Aubyn (Empirical Economics, 24, 23–44, 1999) demonstrates a new paradigm for testing income convergence, or better defined, income stability, namely testing the stationarity of pair-wise income differentials. In this paper, a panel data set of Sub-Saharan African countries is constructed and panel cointegration and unit root tests are used to investigate the convergence properties of incomes and standards of living within Africa. Overall, little evidence is found to substantiate claims of convergence across Africa, although in some cases, smaller convergence clubs within Africa may be found. In addition the use of nonstationary panel data techniques is proposed for the testing and establishing of coherent convergence clubs.     

Are EU budget deficits stationary?

In this paper, we test for the stationarity of European Union budget deficits over the period 1971–2006, using a panel of thirteen member countries. Our testing strategy addresses two key concerns with regard to unit root panel data testing, namely (1) the presence of cross-sectional dependence among the countries in the panel and (2) the identification of potential structural breaks that might have occurred at different points in time. To address these concerns, we employ an AR-based bootstrap approach that allows us to test the null hypothesis of joint stationarity with endogenously determined structural breaks. In contrast to the existing literature, we find that the EU countries considered are characterised by fiscal stationarity over the full sample period irrespective of us allowing for structural breaks. This conclusion also holds when analysing sub-periods based on before and after the Maastricht treaty.     

Is Asian per capita GDP panel stationary?

The goal of this paper is to examine whether per capita GDP for 15 Asian countries is panel stationary. We apply a panel test for stationarity that allows for multiple structural breaks developed by Carrion-i-Silvestre et al. (Econ J 8: 159–179, 2005). Our main findings are: (1) when we apply conventional tests, such as the ADF and KPSS univariate tests without structural breaks, we find little evidence for stationarity; (2) when we apply the KPSS univariate test with multiple structural breaks, we find evidence of stationarity for 10 out of 15 countries; and (3) when we apply the KPSS panel test with multiple structural breaks, we find overwhelming evidence of panel stationarity of per capita real GDP for different panels of Asian countries.      

HYSTERESIS HYPOTHESIS IN UNEMPLOYMENT AND LABOUR FORCE PARTICIPATION RATES: EVIDENCE FROM AUSTRALIAN STATES AND TERRITORIES *

This article simultaneously investigates the hysteresis hypothesis of unemployment and labour force participation using regional level data in Australia. The conventional univariate and panel unit root tests indicate that the hysteresis hypothesis cannot be rejected for most of the regions in Australia. To further confirm if the hysteresis finding in unemployment and labour force participation results from not considering structural breaks. We employ a panel stationarity test recently developed by Carrion‐i‐Silvestre et al. (2005 ), which considers multiple structural breaks and cross‐sectional dependence. The test results lend support for unemployment hysteresis and participation regime‐wise stationarity. Accordingly, the findings imply that a temporary shock may have permanent effects on the unemployment rate but not on labour force participation in Australia and thus call for policies aimed at improving the adjustment mechanism in unemployment.     

The cyclical response of employment to output changes: United States manufacturing industries, 1948 to 1983

This paper provides new evidence on the income elasticity of health care by combining stationarity and cointegration tests of health care expenditure and incomes with estimates of the cointegrating relationship between them. A recently updated dataset of health care expenditures and disposable personal income for the US states for the years 1966–1998 is used. The principal findings are that health care expenditures and incomes at the state level are non-stationary and cointegrated. Dynamic OLS cointegrating regressions of the pooled state time series estimate the income elasticity of health care at 0.817 to 0.844, well below unity, confirming that health care expenditure, even at the aggregate level, is a necessity good.     

Reexamining the income inequality in China: Evidence from sequential panel selection method

This study aims to understand whether incomes across different regions in China are converging or diverging. We propose a novel approach to panel unit root testing–sequential panel selection method (SPSM) by using panel Kapetanios et al. (KSS) test with a Fourier function, which is sufficiently efficient to control for structural breaks and nonlinearity as well as cross-sectional dependency. SPSM classifies the whole panel into a group of stationary and nonstationary series. The method also clearly determines how many and which series in the panel are stationary processes. Using the panel data obtained from 31 regions in China, we find out that the real gross domestic product per capita from 1979 to 2010 does not converge in 20 of the 31 regions in China. The evidence of income divergence has important policy implications for China.     

New evidence on the convergence of international income from a group of 29 countries

This paper updates and extends the time-series evidence on the convergence of international incomes using a set of 29 countries over the period 1900–2001. Time-series tests for stochastic convergence are supplemented with tests which provide evidence on the notion of “β-convergence” predicted by the Solow model. The evidence indicates that the relative income series of 21 countries are consistent with stochastic convergence, and that β-convergence has occurred in at least 16 countries at some point during the twentieth century. Further examination of the properties of the β-convergence test provides anecdotal evidence of conditional convergence in three additional countries for which the convergence hypothesis was initially rejected. Consideration of convergence clubs strengthens the evidence in favor of convergence. Analysis of the cross-country dispersion of incomes over time also suggests that convergence has occurred over the 1900–2001 period, particularly within certain clubs, with structural breaks associated with World War II in many countries causing a break in the convergence process.      

Convergence in income inequality? evidence from panel unit root tests with structural breaks

This paper empirically tests whether there is evidence of convergence in income inequality, as predicted by several versions of the neoclassical growth model, using a large panel of annual data for the 48 contiguous states in the US over the 1916?C2005 period. By implementing the panel LM unit root test developed by Im et?al. (Oxford Bull Econ Stat 67:393?C419, 2005, Panel LM unit-root tests with trend shifts, Mimeo, 2010) that allows for the presence of structural breaks and heterogeneity in the panel, we find overwhelming evidence in support of convergence in income inequality. In addition, the results are robust to alternative inequality indicators used, different notions of stochastic convergence defined, and additional cross-sectional correlation considered.     

Multimodality in the distribution of GDP and the absolute convergence hypothesis

This article shows that, contrary to common wisdom, the insurgence of a multiplicity of clusters in the distribution of income is not necessarily against the hypothesis of absolute convergence. Using data for the world economies, the US states, the EU regions, and the Italian regions, we find that despite the distribution of income per capita for both the world economies and for the Italian regions is multimodal, only in the former case absolute convergence can be rejected. Similarly, although the distributions for the EU regions and the US states are both unimodal, convergence is unambiguously taking place in the latter case only. We show that these results are consistent with the neoclassical model of growth in the presence of non-convexities in production. We conclude that polarization in the distribution of per capita incomes is neither a sufficient nor a necessary condition to reject the absolute convergence hypothesis.     

Club convergence and clustering of U.S. energy-related CO2 emissions

This study examines the convergence of energy-related carbon dioxide emissions among a panel of U.S. states between the period 1960–2010. This examination is carried out by means of a two-stage procedure. In the first stage, we conduct an endogenous grouping, regression-based convergence test. Unlike previous studies, this methodology endogenously identifies groups of states with emissions that are converging to a similar steady state growth path over time. In the second stage, we evaluate the conditional rate of convergence for the whole sample and for each club using panel data, fixed effects models that control for unobserved, time-invariant heterogeneous effects. More specifically, we examine the rates of convergence conditional on certain structural and non-structural characteristics of the state economy. Results from stage one and stage two suggest that one group of twenty-six states is converging to a unique steady-state equilibrium, and otherwise, the remaining states are diverging. Finally, we discuss different policy approaches to mitigating carbon dioxide emissions based on the club convergence hypothesis.     

Heterogeneous technology and the technological catching-up hypothesis: Theory and assessment in the case of MENA countries

Long run convergence implies that the convergence hypothesis will be rejected if the income differential is not stationary. However, this definition is valid only if the catching-up process between the two countries is already over. If we take into account catching-up dynamics, then poorest countries should obtain a faster growth than developed countries. Thus, income gaps should integrate decreasing time trends. We formalise this hypothesis theoretically using a stochastic neoclassical growth model with heterogeneous technology. We then apply this model to the issue of per-capita GDP catching-up of eight MENA countries towards the level of income in Europe. We approximate the nonlinear deterministic trend by a linear function with breaks and apply panel unit root tests with breaks. The analysis reveals firstly that the periods of divergence outnumber the periods of convergence. Secondly, since the year 2000 all countries but Syria have been converging toward the European per-capita income level.     

Stochastic convergence of the catch-up rate and multiple structural breaks in Asian countries

Allowing for multiple structural breaks and cross-section dependence, we re-investigate the hypothesis that the catch-up rates stochastically converge for 13 Asian countries from 1960 to 2007. Non-rejection of stationarity provides evidence for stochastic convergence, implying that following shocks to the catch-up rate, it will eventually revert to its long-run level.     

A pair-wise approach to output convergence between European regions

We apply the Pesaran (2007) pair-wise approach of convergence to the per capita outputs of 195 European regions for the period 1980-2006. Pesaran's approach is based on the computation of the percentage ratio of output gaps which fulfil a given convergence criterion. A high ratio will be interpreted in favour of convergence. In a first step, we define stochastic convergence between two regions as level stationarity of their output gap. Deviations from its equilibrium value will only have a temporary effect. Results from several usual unit root or stationarity tests show us that the percentage ratio of level stationary output gaps is low, which stands against this definition of convergence. However, this convergence criterion excludes the possibility of changes in output gap equilibrium value or catching up between regions. To fit these cases, we combine the pair-wise approach with unit root or stationarity tests with structural breaks. Structural breaks are modelled by dummies (Zivot and Andrews, 1992; Kurozumi,2002) or as smooth structural breaks (Christopoulos and León-Ledesma, 2009). Overall results are not changed as convergence is not accepted more often. Finally, we consider the autocorrelation function approach of Caggiano and Leonida (2009). Autocorrelations and their confidence intervals are estimated for each output gap. Convergence between two regions is accepted if their per capita output gap autocorrelations become nonsignificantly different from zero after some lag. Results show that a high percentage of regions satisfy this convergence criterion. Contrary to the conclusions which could be made from previous results, shocks to output gaps seem to disappear as time passes.     

The term structure of interest rates,the expectations hypothesis and international financial integration: Evidence from Asian economies

The validity of the expectations hypothesis of the term structure is examined for a sample of Asian countries. A panel stationarity testing procedure is employed that addresses both structural breaks and cross-sectional dependence. Asian term structures are found to be stationary and supportive of the expectations hypothesis. Further analysis suggests that international financial integration is associated with interdependencies between domestic and foreign term structures insofar as cross-term structures based on differentials between domestic (foreign) short- and foreign (domestic) long-rates are also stationary.     

Is fiscal policy stationary in China? A regional study by local government

In this study, we apply a stationarity test with a flexible Fourier function proposed by Enders and Lee (2012) to test the stationarity of the deficit–GDP ratio in China. We find that our approximation has a higher power to detect U-shaped breaks and to smooth breaks than the linear method if the true data-generating process of the deficit–GDP ratio convergence is, in fact, a stationary non-linear process. The results show that the stationarity for fiscal policy varies across different regions and that the deficit–GDP ratio of half of the regions is stationary. The results related to the budget structural balance and the fiscal deficit indicate no expansion in the Eastern and Central regions. We find that China's provinces in these two regions meet the stability theory of fiscal policy in the current stage of development. The deficit–GDP ratio is not stationary in the Western and Northeastern regions. These results indicate that the fiscal deficits in these regions are expanding and cannot be controlled by automatic market adjustment, and the government should therefore avoid deficit expansion in favor of a balanced budget policy.     

HYSTERESIS IN UNEMPLOYMENT REVISITED: EVIDENCE FROM PANEL LM UNIT ROOT TESTS WITH HETEROGENEOUS STRUCTURAL BREAKS

This paper applies the panel LM unit root tests with heterogeneous structural breaks in level by Im  et al. ( Oxford Bulletin of Economics and Statistics , 67 (2005), pp. 393–419) to re-examine the validity of hysteresis in the unemployment rates of 19 OECD countries. Our empirical findings are favourable to the stationarity of the unemployment rates, i.e., the unemployment hysteresis hypothesis is strongly rejected. Our results suggest that shocks to unemployment rates are temporary and soon converge when we control for breaks. A major policy implication of the study is that a fiscal or monetary stabilization policy would not have permanent effects on the unemployment rates of the 19 OECD countries.