This paper examines lag selection problem in unit root tests which has become a major specification problem in empirical analysis of non-stationary time series data. It is known that the implementation of unit root tests requires the choice of optimal truncation lag for good power proper ties and it is equally unrealistic to assume that the true optimal truncation lag is known a prior to the practitioners and other applied researchers. Consequently, these users rely largely on the use of standard information criteria for selection of truncation lag in unit root tests. A number of previous studies have shown that these criteria have problem of over-specification of truncation lag-length leading to the well-known low power problem that is commonly associated with most unit root tests in the literature. This paper focuses on the problem of over-specification of truncation lag-length within the context of augmented Dickey-Fuller (ADF) and generalized least squares Dickey-Fuller (DF-GLS)unit root tests. In an attempt to address this lag selection problem, we propose a new criterion for the selection of truncation lag in unit root tests based on Koyck distributed lag model and we show that this new criterion avoids the problem of over-specification of truncationlag-length that is commonly associated with standard information criteria.
Published in | American Journal of Theoretical and Applied Statistics (Volume 2, Issue 6) |
DOI | 10.11648/j.ajtas.20130206.28 |
Page(s) | 293-298 |
Creative Commons |
This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited. |
Copyright |
Copyright © The Author(s), 2014. Published by Science Publishing Group |
Truncation Lag, Information Criteria, Koyck Distributed Lag Model, Unit Root Test, Low Power, Partial Correlation Coefficient
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APA Style
Agunloye, Oluokun Kasali, Arnab, Raghunath, Shangodoyin, et al. (2014). A New Criterion for Lag-Length Selection in Unit Root Tests. American Journal of Theoretical and Applied Statistics, 2(6), 293-298. https://doi.org/10.11648/j.ajtas.20130206.28
ACS Style
Agunloye; Oluokun Kasali; Arnab; Raghunath; Shangodoyin, et al. A New Criterion for Lag-Length Selection in Unit Root Tests. Am. J. Theor. Appl. Stat. 2014, 2(6), 293-298. doi: 10.11648/j.ajtas.20130206.28
AMA Style
Agunloye, Oluokun Kasali, Arnab, Raghunath, Shangodoyin, et al. A New Criterion for Lag-Length Selection in Unit Root Tests. Am J Theor Appl Stat. 2014;2(6):293-298. doi: 10.11648/j.ajtas.20130206.28
@article{10.11648/j.ajtas.20130206.28, author = {Agunloye and Oluokun Kasali and Arnab and Raghunath and Shangodoyin and Dahud Kehinde}, title = {A New Criterion for Lag-Length Selection in Unit Root Tests}, journal = {American Journal of Theoretical and Applied Statistics}, volume = {2}, number = {6}, pages = {293-298}, doi = {10.11648/j.ajtas.20130206.28}, url = {https://doi.org/10.11648/j.ajtas.20130206.28}, eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ajtas.20130206.28}, abstract = {This paper examines lag selection problem in unit root tests which has become a major specification problem in empirical analysis of non-stationary time series data. It is known that the implementation of unit root tests requires the choice of optimal truncation lag for good power proper ties and it is equally unrealistic to assume that the true optimal truncation lag is known a prior to the practitioners and other applied researchers. Consequently, these users rely largely on the use of standard information criteria for selection of truncation lag in unit root tests. A number of previous studies have shown that these criteria have problem of over-specification of truncation lag-length leading to the well-known low power problem that is commonly associated with most unit root tests in the literature. This paper focuses on the problem of over-specification of truncation lag-length within the context of augmented Dickey-Fuller (ADF) and generalized least squares Dickey-Fuller (DF-GLS)unit root tests. In an attempt to address this lag selection problem, we propose a new criterion for the selection of truncation lag in unit root tests based on Koyck distributed lag model and we show that this new criterion avoids the problem of over-specification of truncationlag-length that is commonly associated with standard information criteria.}, year = {2014} }
TY - JOUR T1 - A New Criterion for Lag-Length Selection in Unit Root Tests AU - Agunloye AU - Oluokun Kasali AU - Arnab AU - Raghunath AU - Shangodoyin AU - Dahud Kehinde Y1 - 2014/01/30 PY - 2014 N1 - https://doi.org/10.11648/j.ajtas.20130206.28 DO - 10.11648/j.ajtas.20130206.28 T2 - American Journal of Theoretical and Applied Statistics JF - American Journal of Theoretical and Applied Statistics JO - American Journal of Theoretical and Applied Statistics SP - 293 EP - 298 PB - Science Publishing Group SN - 2326-9006 UR - https://doi.org/10.11648/j.ajtas.20130206.28 AB - This paper examines lag selection problem in unit root tests which has become a major specification problem in empirical analysis of non-stationary time series data. It is known that the implementation of unit root tests requires the choice of optimal truncation lag for good power proper ties and it is equally unrealistic to assume that the true optimal truncation lag is known a prior to the practitioners and other applied researchers. Consequently, these users rely largely on the use of standard information criteria for selection of truncation lag in unit root tests. A number of previous studies have shown that these criteria have problem of over-specification of truncation lag-length leading to the well-known low power problem that is commonly associated with most unit root tests in the literature. This paper focuses on the problem of over-specification of truncation lag-length within the context of augmented Dickey-Fuller (ADF) and generalized least squares Dickey-Fuller (DF-GLS)unit root tests. In an attempt to address this lag selection problem, we propose a new criterion for the selection of truncation lag in unit root tests based on Koyck distributed lag model and we show that this new criterion avoids the problem of over-specification of truncationlag-length that is commonly associated with standard information criteria. VL - 2 IS - 6 ER -