The impact of the initial condition on covariate augmented unit root tests

We examine the behaviour of OLS-demeaned/detrended and GLS-demeaned/detrended unit root tests that employ stationary covariates, as proposed by Hansen (1995, “Rethinking the Univariate Approach to Unit Root Testing.” Econometric Theory 11:1148–71) and Elliott and Jansson (2003, “Testing for Unit Roo...

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Main Authors: Aristidou, Chrystalleni, Harvey, David I., Leybourne, Stephen J.
Format: Article
Published: De Gruyter 2016
Subjects:
Online Access:https://eprints.nottingham.ac.uk/32655/
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author Aristidou, Chrystalleni
Harvey, David I.
Leybourne, Stephen J.
author_facet Aristidou, Chrystalleni
Harvey, David I.
Leybourne, Stephen J.
author_sort Aristidou, Chrystalleni
building Nottingham Research Data Repository
collection Online Access
description We examine the behaviour of OLS-demeaned/detrended and GLS-demeaned/detrended unit root tests that employ stationary covariates, as proposed by Hansen (1995, “Rethinking the Univariate Approach to Unit Root Testing.” Econometric Theory 11:1148–71) and Elliott and Jansson (2003, “Testing for Unit Roots with Stationary Covariates.” Journal of Econometrics 115:75–89), respectively, in situations where the magnitude of the initial condition of the time series under consideration may be non-negligible. We show that the asymptotic power of such tests is very sensitive to the initial condition; OLS- and GLS-based tests achieve relatively high power for large and small magnitudes of the initial condition, respectively. Combining information from both types of test via a simple union of rejections strategy is shown to effectively capture the higher power available across all initial condition magnitudes.
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spelling nottingham-326552020-05-04T17:40:31Z https://eprints.nottingham.ac.uk/32655/ The impact of the initial condition on covariate augmented unit root tests Aristidou, Chrystalleni Harvey, David I. Leybourne, Stephen J. We examine the behaviour of OLS-demeaned/detrended and GLS-demeaned/detrended unit root tests that employ stationary covariates, as proposed by Hansen (1995, “Rethinking the Univariate Approach to Unit Root Testing.” Econometric Theory 11:1148–71) and Elliott and Jansson (2003, “Testing for Unit Roots with Stationary Covariates.” Journal of Econometrics 115:75–89), respectively, in situations where the magnitude of the initial condition of the time series under consideration may be non-negligible. We show that the asymptotic power of such tests is very sensitive to the initial condition; OLS- and GLS-based tests achieve relatively high power for large and small magnitudes of the initial condition, respectively. Combining information from both types of test via a simple union of rejections strategy is shown to effectively capture the higher power available across all initial condition magnitudes. De Gruyter 2016-03-25 Article PeerReviewed Aristidou, Chrystalleni, Harvey, David I. and Leybourne, Stephen J. (2016) The impact of the initial condition on covariate augmented unit root tests. Journal of Time Series Econometrics, 9 (1). ISSN 1941-1928 Unit root tests; stationary covariates; initial condition uncertainty; asymptotic power https://www.degruyter.com/view/j/jtse.2017.9.issue-1/jtse-2015-0013/jtse-2015-0013.xml doi:10.1515/jtse-2015-0013 doi:10.1515/jtse-2015-0013
spellingShingle Unit root tests; stationary covariates; initial condition uncertainty; asymptotic power
Aristidou, Chrystalleni
Harvey, David I.
Leybourne, Stephen J.
The impact of the initial condition on covariate augmented unit root tests
title The impact of the initial condition on covariate augmented unit root tests
title_full The impact of the initial condition on covariate augmented unit root tests
title_fullStr The impact of the initial condition on covariate augmented unit root tests
title_full_unstemmed The impact of the initial condition on covariate augmented unit root tests
title_short The impact of the initial condition on covariate augmented unit root tests
title_sort impact of the initial condition on covariate augmented unit root tests
topic Unit root tests; stationary covariates; initial condition uncertainty; asymptotic power
url https://eprints.nottingham.ac.uk/32655/
https://eprints.nottingham.ac.uk/32655/
https://eprints.nottingham.ac.uk/32655/