Gencay, Ramazan and Fan, Yanqin (2007): Unit Root Tests with Wavelets.
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Abstract
This paper develops a wavelet (spectral) approach to test the presence of a unit root in a stochastic process. The wavelet approach is appealing, since it is based directly on the different behavior of the spectra of a unit root process and that of a short memory stationary process. By decomposing the variance (energy) of the underlying process into the variance of its low frequency components and that of its high frequency components via the discrete wavelet transformation (DWT), we design unit root tests against near unit root alternatives. Since DWT is an energy preserving transformation and able to disbalance energy across high and low frequency components of a series, it is possible to isolate the most persistent component of a series in a small number of scaling coefficients. We demonstrate the size and power properties of our tests through Monte Carlo simulations.
Item Type:  MPRA Paper 

Original Title:  Unit Root Tests with Wavelets 
Language:  English 
Keywords:  Unit root tests, discrete wavelet transformation, maximum overlap wavelet transformation, energy decomposition 
Subjects:  C  Mathematical and Quantitative Methods > C3  Multiple or Simultaneous Equation Models; Multiple Variables C  Mathematical and Quantitative Methods > C5  Econometric Modeling C  Mathematical and Quantitative Methods > C2  Single Equation Models; Single Variables C  Mathematical and Quantitative Methods > C1  Econometric and Statistical Methods and Methodology: General C  Mathematical and Quantitative Methods > C4  Econometric and Statistical Methods: Special Topics 
Item ID:  9832 
Depositing User:  Ramazan Gencay 
Date Deposited:  09. Sep 2008 06:25 
Last Modified:  02. Mar 2013 15:40 
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URI:  http://mpra.ub.unimuenchen.de/id/eprint/9832 
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