Scale of variance, unit of data and the power of unit root tests under structural changes - a strategy for analysing Nelson-Plosser data
Lee and Strazicich (LS) designed a state-of-the-art statistic for testing for a unit root under structural changes. Using Monte Carlo experiments on the Nelson and Plosser data, this present study analyses the effects of scale of variance and data unit on the size-adjusted power of the LS unit root test. It is found that under the null and the alternative hypotheses of unit root shifts from right to left, the goodness of fit of the statistic worsens, and the power increases systematically when the scale of variance increases from 0.01 w to w and from w to 100 w (w being a weighting factor). The power increases when the data unit is reduced to one tenth and per cent (i.e. one hundredth) except for the Industrial Production Index, Total Unemployment Rate and Nominal Wages. To achieve the goal of higher power and better goodness of fit in the LS test, results suggest using the original variance rather than the best goodness-of-fit variance, changing the data unit to per cent, or using a mixed strategy selecting the data unit corresponding to a higher power for each data series.
Volume (Year): 13 (2006)
Issue (Month): 1 ()
|Contact details of provider:|| Web page: http://www.tandfonline.com/RAEL20|
|Order Information:||Web: http://www.tandfonline.com/pricing/journal/RAEL20|
References listed on IDEAS
Please report citation or reference errors to , or , if you are the registered author of the cited work, log in to your RePEc Author Service profile, click on "citations" and make appropriate adjustments.:
- Zivot, Eric & Andrews, Donald W K, 1992.
"Further Evidence on the Great Crash, the Oil-Price Shock, and the Unit-Root Hypothesis,"
Journal of Business & Economic Statistics,
American Statistical Association, vol. 10(3), pages 251-270, July.
- Zivot, Eric & Andrews, Donald W K, 2002. "Further Evidence on the Great Crash, the Oil-Price Shock, and the Unit-Root Hypothesis," Journal of Business & Economic Statistics, American Statistical Association, vol. 20(1), pages 25-44, January.
- Tom Doan, "undated". "ZIVOT: RATS procedure to perform Zivot-Andrews Unit Root Test," Statistical Software Components RTS00236, Boston College Department of Economics.
- Eric Zivot & Donald W.K. Andrews, 1990. "Further Evidence on the Great Crash, the Oil Price Shock, and the Unit Root Hypothesis," Cowles Foundation Discussion Papers 944, Cowles Foundation for Research in Economics, Yale University.
- Amsler, Christine & Lee, Junsoo, 1995. "An LM Test for a Unit Root in the Presence of a Structural Change," Econometric Theory, Cambridge University Press, vol. 11(02), pages 359-368, February.
- Junsoo Lee & Mark C. Strazicich, 2003. "Minimum Lagrange Multiplier Unit Root Test with Two Structural Breaks," The Review of Economics and Statistics, MIT Press, vol. 85(4), pages 1082-1089, November.
- Nelson, Charles R. & Plosser, Charles I., 1982. "Trends and random walks in macroeconmic time series : Some evidence and implications," Journal of Monetary Economics, Elsevier, vol. 10(2), pages 139-162.
- Lee, Junsoo & Strazicich, Mark C, 2001. " Break Point Estimation and Spurious Rejections with Endogenous Unit Root Tests," Oxford Bulletin of Economics and Statistics, Department of Economics, University of Oxford, vol. 63(5), pages 535-558, December.
When requesting a correction, please mention this item's handle: RePEc:taf:apeclt:v:13:y:2006:i:1:p:51-56. See general information about how to correct material in RePEc.
For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: (Michael McNulty)
If references are entirely missing, you can add them using this form.