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On the Limit Theory of Mixed to Unity VARs: Panel Setting with Weakly Dependent Errors

Stauskas, Ovidijus LU (2020) In Journal of Time Series Analysis 41(6). p.892-898
Abstract
In this article, we re‐visit a recent idea of Phillips and Lee (2015. Econometric Reviews 34: 1035 ‐ 1056). They examine an empirically relevant situation when two time series exhibit different degrees of non‐stationarity and one need to learn whether their persistence properties are the same. By bridging the asymptotic theory of local to unity and mildly explosive processes, they construct a Wald test for the commonality of the long‐run behavior of the series. However, inference is complicated by the fact that their statistic does not converge in distribution under the null and diverges under the alternative. This is true if the parameters of the data generating process are known and a re‐normalizing function can be constructed. If the... (More)
In this article, we re‐visit a recent idea of Phillips and Lee (2015. Econometric Reviews 34: 1035 ‐ 1056). They examine an empirically relevant situation when two time series exhibit different degrees of non‐stationarity and one need to learn whether their persistence properties are the same. By bridging the asymptotic theory of local to unity and mildly explosive processes, they construct a Wald test for the commonality of the long‐run behavior of the series. However, inference is complicated by the fact that their statistic does not converge in distribution under the null and diverges under the alternative. This is true if the parameters of the data generating process are known and a re‐normalizing function can be constructed. If the parameters are unknown, which will be the case in practice, the test statistic may be divergent even under the null. We solve this problem by converting the original setting of vector time series into a panel setting with N individual vector series. We show that the proposed panel Wald test statistics converge to chi‐squared distribution which is free of nuisance parameters under the null hypothesis of common local to unity behavior. The result is an extreme example of simplified asymptotics brought about by panel data. (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Local to unity, Mildly explosive, Panel, Weak dependence, Wald test
in
Journal of Time Series Analysis
volume
41
issue
6
pages
7 pages
publisher
Wiley-Blackwell
external identifiers
  • scopus:85084522804
ISSN
0143-9782
DOI
10.1111/jtsa.12530
language
English
LU publication?
yes
id
b0fccff3-b7f6-46b4-af26-9d0d16a5aeed
date added to LUP
2020-05-15 09:07:02
date last changed
2022-04-18 22:27:51
@article{b0fccff3-b7f6-46b4-af26-9d0d16a5aeed,
  abstract     = {{In this article, we re‐visit a recent idea of Phillips and Lee (2015. Econometric Reviews 34: 1035 ‐ 1056). They examine an empirically relevant situation when two time series exhibit different degrees of non‐stationarity and one need to learn whether their persistence properties are the same. By bridging the asymptotic theory of local to unity and mildly explosive processes, they construct a Wald test for the commonality of the long‐run behavior of the series. However, inference is complicated by the fact that their statistic does not converge in distribution under the null and diverges under the alternative. This is true if the parameters of the data generating process are known and a re‐normalizing function can be constructed. If the parameters are unknown, which will be the case in practice, the test statistic may be divergent even under the null. We solve this problem by converting the original setting of vector time series into a panel setting with N individual vector series. We show that the proposed panel Wald test statistics converge to chi‐squared distribution which is free of nuisance parameters under the null hypothesis of common local to unity behavior. The result is an extreme example of simplified asymptotics brought about by panel data.}},
  author       = {{Stauskas, Ovidijus}},
  issn         = {{0143-9782}},
  keywords     = {{Local to unity; Mildly explosive; Panel; Weak dependence; Wald test}},
  language     = {{eng}},
  number       = {{6}},
  pages        = {{892--898}},
  publisher    = {{Wiley-Blackwell}},
  series       = {{Journal of Time Series Analysis}},
  title        = {{On the Limit Theory of Mixed to Unity VARs: Panel Setting with Weakly Dependent Errors}},
  url          = {{http://dx.doi.org/10.1111/jtsa.12530}},
  doi          = {{10.1111/jtsa.12530}},
  volume       = {{41}},
  year         = {{2020}},
}