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Testing for nonlinear panel unit roots under cross-sectional dependency — With an application to the PPP hypothesis


  • Månsson, Kristofer
  • Sjölander, Pär


In this paper we propose a number of nonlinear panel unit root tests that are robust to cross-sectional dependency. These tests may be used to test the null hypothesis of non-stationarity against the alternative that some or all of the time series in the system of equations follow a stationary exponential smooth transition autoregressive (ESTAR) process. In contrast to previous research we relax the assumption that the cross-correlation structure is driven by a common-factor and consider an endogenous correlation structure. Based on the size and power results from the Monte Carlo simulations we recommend using the Wald version of our cross-sectional dependent robust nonlinear panel unit root (CDR-NPU) method.

Suggested Citation

  • Månsson, Kristofer & Sjölander, Pär, 2014. "Testing for nonlinear panel unit roots under cross-sectional dependency — With an application to the PPP hypothesis," Economic Modelling, Elsevier, vol. 38(C), pages 121-132.
  • Handle: RePEc:eee:ecmode:v:38:y:2014:i:c:p:121-132 DOI: 10.1016/j.econmod.2013.12.013

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    References listed on IDEAS

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    Cited by:

    1. Emirmahmutoglu, Furkan & Omay, Tolga, 2014. "Reexamining the PPP hypothesis: A nonlinear asymmetric heterogeneous panel unit root test," Economic Modelling, Elsevier, vol. 40(C), pages 184-190.

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    Panel data; Unit roots; Nonlinearity; ESTAR;


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