We propose a nonlinear heterogeneous panel unit root test for testing the null hypothesis of unit-root processes against the alternative that allows a proportion of units to be generated by globally stationary ESTAR processes and a remaining non-zero proportion to be generated by unit root processes. The proposed test is simple to apply and accommodates cross section dependence. Monte Carlo sim...

This paper re-assesses the panel (unit root test) evidence for PPP on four monthly data sets. We discuss and illustrate that commonly-used first generation panel unit root tests are inappropriate for PPP analysis since they are constructed for cross-sectionally uncorrelated panels. Given that real exchange rate panel data sets are – almost by construction – highly cross-sectionally correlated, ...

This paper investigates Gibrat’s law by using a panel unit root test, as a panel unit root can increase power in contrast to a conventional individual ADF test. At first this paper uses the panel unit root test to testify Gibrat’s law under independent and identical distribution, with the test results rejecting the null hypothesis of Gibrat’s law. Independent and identical distributions are not...

This paper proposes a new panel unit root test based on Simes’ [Biometrika 1986, “An Improved Bonferroni Procedure for Multiple Tests of Significance”] classical intersection test. The test is robust to general patterns of cross-sectional dependence and yet straightforward to implement, only requiring p-values of time series unit root tests of the series in the panel, and no resampling. Monte C...

This paper proposes a new panel unit root test based on Simes’ [Biometrika 1986, “An Improved Bonferroni Procedure for Multiple Tests of Significance”] classical intersection test. The test is robust to general patterns of cross-sectional dependence and yet straightforward to implement, only requiring p-values of time series unit root tests of the series in the panel, and no resampling. Monte C...

This paper proposes a new panel unit root test based on Simes’ [Biometrika 1986, “An Improved Bonferroni Procedure for Multiple Tests of Significance”] classical intersection test. The test is robust to general patterns of cross-sectional dependence and yet straightforward to implement, only requiring p-values of time series unit root tests of the series in the panel, and no resampling. Monte C...

We propose a unit root test for panels with cross-sectional dependency. We allow general dependency structure among the innovations that generate data for each of the cross-sectional units. Each unit may have di®erent sample size, and therefore unbalanced panels are also permitted in our framework. Yet, the test is asymptotically normal, and does not require any tabulation of the critical value...

This article proposes a simple estimator that is consistent for the fraction of a panel that has an autoregressive unit root. Given such an estimate, θ̂ , we can test the null hypothesis that θ = θ0 for any value of θ0 ∈ (0,1]. The test is asymptotically standard normal and is valid whether or not the panel is crosssectionally correlated. The main insight is that in a panel in which some units a...