Hostname: page-component-77c89778f8-swr86 Total loading time: 0 Render date: 2024-07-21T02:08:36.958Z Has data issue: false hasContentIssue false

UNIT ROOT TEST IN A THRESHOLD AUTOREGRESSION: ASYMPTOTIC THEORY AND RESIDUAL-BASED BLOCK BOOTSTRAP

Published online by Cambridge University Press:  17 July 2008

Myung Hwan Seo*
Affiliation:
London School of Economics
*
Address correspondence to Myung Hwan Seo, Department of Economics, London School of Economics, Houghton Street, London, WC2A 2AE, United Kingdom; e-mail: m.seo@lse.ac.uk

Abstract

This paper develops a test of the unit root null hypothesis against a stationary threshold process. This testing problem is nonstandard and complicated because a parameter is unidentified and the process is nonstationary under the null hypothesis. We derive an asymptotic distribution for the test, which is not pivotal without simplifying assumptions. A residual-based block bootstrap is proposed to calculate the asymptotic p-values. The asymptotic validity of the bootstrap is established, and a set of Monte Carlo simulations demonstrates its finite-sample performance. In particular, the test exhibits considerable power gains over the augmented Dickey–Fuller (ADF) test, which neglects threshold effects.

Type
Research Article
Copyright
Copyright © Cambridge University Press 2008

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Balke, N. & Fomby, T. (1997) Threshold cointegration. International Economic Review 38, 627645.CrossRefGoogle Scholar
Basawa, I.V., Mallik, A.K., McCormick, W.P., Reeves, J.H., & Taylor, R.L. (1991) Bootstrapping unstable first-order autoregressive processes. Annals of Statistics 19, 10981101.CrossRefGoogle Scholar
Bec, F., Guay, A., & Guerre, E. (2008) Adaptive consistent unit root tests based on autoregressive threshold model. Journal of Econometrics 142, 94133.CrossRefGoogle Scholar
Bec, F. & Rahbek, A. (2004) Vector equilibrium correction models with non-linear discontinuous adjustments. Econometrics Journal 7, 628651.CrossRefGoogle Scholar
Caner, M. & Hansen, B.E. (2001) Threshold autoregression with a unit root. Econometrica 69, 15551596.CrossRefGoogle Scholar
Chan, K.S., Petruccelli, J.D., Tong, H., & Woolford, S.W. (1985) A multiple-threshold AR(1) model. Journal of Applied Probability 22, 267279.CrossRefGoogle Scholar
Davies, R. (1987) Hypothesis testing when a nuisance parameter is present only under the alternative. Biometrika 74, 3343.Google Scholar
Enders, W. & Granger, C. (1998) Unit root tests and asymmetric adjustment with an example using the term structure of interest rates. Journal of Business & Economic Statistics 16, 304311.Google Scholar
Hall, P., Horowitz, J.L., & Jing, B.-Y. (1995) On blocking rules for the bootstrap with dependent data. Biometrika 82, 561574.CrossRefGoogle Scholar
Hansen, B. (1992) Convergence to stochastic integrals for dependent heterogeneous processes. Econometric Theory 8, 489500.CrossRefGoogle Scholar
Hansen, B. (1999) Testing for linearity. Journal of Economic Surveys 13, 551576.CrossRefGoogle Scholar
Kapetanios, G. & Shin, Y. (2006) Unit root tests in three-regime SETAR models. Econometrics Journal 9, 252278.CrossRefGoogle Scholar
Künsch, H.R. (1989) The jackknife and the bootstrap for general stationary observations. Annals of Statistics 17, 12171241.CrossRefGoogle Scholar
Kurtz, T. & Protter, P. (1991) Weak limit theorems for stochastic integrals and stochastic differential equations. Annals of Probability 19, 10351070.CrossRefGoogle Scholar
Lo, M. & Zivot, E. (2001) Threshold cointegration and nonlinear adjustment to the law of one price. Macroeconomic Dynamics 5, 533576.CrossRefGoogle Scholar
Ng, S. & Perron, P. (1995) Unit root tests in ARMA models with data-dependent methods for the selection of the truncation lag. Journal of the American Statistical Association 90, 268281.CrossRefGoogle Scholar
Paparoditis, E. & Politis, D.N. (2003) Residual-based block bootstrap for unit root testing. Econometrica 71, 813855.CrossRefGoogle Scholar
Park, J. (2002) On invariance principle for sieve bootstrap in time series. Econometric Theory 18, 469490.CrossRefGoogle Scholar
Park, J. & Phillips, P. (2001) Nonlinear regressions with integrated time series. Econometrica 69, 117161.CrossRefGoogle Scholar
Park, J. & Shintani, M. (2005) Testing for a Unit Root against Transitional Autoregressive Models. Mimeo, Vanderbilt University.Google Scholar
Perron, P. (1989) The great crash, the oil price shock and the unit root hypothesis. Econometrica 57, 13611401.CrossRefGoogle Scholar
Phillips, P.C.B. & Perron, P. (1988) Testing for a unit root in time series regression. Biometrika 75, 335346.CrossRefGoogle Scholar
Said, S.E. & Dickey, D.A. (1984) Testing for unit roots in autoregressive-moving average models of unknown order. Biometrika 71, 599607.CrossRefGoogle Scholar
Seo, M. (2005) Unit Root Test in a Threshold Autoregression: Asymptotic Theory and Residual-Based Block Bootstrap. Mimeo, London School of Economics, http://sticerd.lse.ac.uk/dps/em/em484.pdf.Google Scholar
Seo, M. (2006) Bootstrap testing for the null of no cointegration in a threshold vector error correction model. Journal of Econometrics 134, 129150.CrossRefGoogle Scholar
Tong, H. (1990) Nonlinear Time Series. Oxford University Press.Google Scholar
Wooldridge, J.M. & White, H. (1988) Some invariance principles and central limit theorems for dependent heterogeneous processes. Econometric Theory 4, 210230.CrossRefGoogle Scholar