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Time Series Regression with Mixtures of Integrated Processes

Published online by Cambridge University Press:  11 February 2009

Yoosoon Chang
Affiliation:
Rice University
Peter C.B. Phillips
Affiliation:
Cowles Foundation for Research in Economics Yale University

Abstract

The paper develops a statistical theory for regressions with integrated regressors of unknown order and unknown cointegrating dimension. In practice, we are often unsure whether unit roots or cointegration is present in time series data, and we are also uncertain about the order of integration in some cases. This paper addresses issues of estimation and inference in cases of such uncertainty. Phillips (1995, Econometrica 63, 1023–1078) developed a theory for time series regressions with an unknown mixture of 1(0) and 1(1) variables and established that the method of fully modified ordinary least squares (FM-OLS) is applicable to models (including vector autoregressions) with some unit roots and unknown cointegrating rank. This paper extends these results to models that contain some I(0), I(1), and I(2) regressors. The theory and methods here are applicable to cointegrating regressions that include unknown numbers of I(0), I(1), and I(2) variables and an unknown degree of cointegration. Such models require a somewhat different approach than that of Phillips (1995). The paper proposes a residual-based fully modified ordinary least-squares (RBFMOLS) procedure, which employs residuals from a first-order autoregression of the first differences of the entire regressor set in the construction of the FMOLS estimator. The asymptotic theory for the RBFM-OLS estimator is developed and is shown to be normal for all the stationary coefficients and mixed normal for all the nonstationary coefficients. Under Gaussian assumptions, estimation of the cointegration space by RBFM-OLS is optimal even though the dimension of the space is unknown.

Type
Articles
Copyright
Copyright © Cambridge University Press 1995

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References

REFERENCES

Andrews, D.W.K. (1991) Heteroskedasticity and autocorrelation consistent covariance matrix estimation. Econometrica 59, 817858.CrossRefGoogle Scholar
Chang, Y. (1993) Fully Modified Estimation of Cointegrated Systems with 1(2) Processes. Mimeo, Yale University.Google Scholar
Chang, Y. & Phillips, P.C.B. (1994) Fully Modified Regressions with an Unknown Mixture of I(0) and I(2) Regressors. Mimeo, Yale University.Google Scholar
Engle, R.F. & Granger, C.W.J. (1987) Co-integration and error correction: Representation, estimation and testing. Econometrica 55, 251276.CrossRefGoogle Scholar
Engle, R.F. & Yoo, B.S. (1991) Cointegrated economic time series: A survey with new results. In Granger, C.W.J. & Engle, R.F. (eds.), Long-Run Economic Relations: Readings in Cointegration, pp. 237266. Oxford: Oxford University Press.CrossRefGoogle Scholar
Granger, C.W.J. (1981) Some properties of time series data and their use in econometric model specification. Journal of Econometrics 2.Google Scholar
Hannan, E.J. (1970) Multiple Time Series. New York: John Wiley & Sons.CrossRefGoogle Scholar
Hansen, B.E. & Phillips, P.C.B. (1991) Estimation and inference in models of cointegration: A simulation study. Advances in Econometrics 8, 225248.Google Scholar
Hargreaves, C.H. (1993) A review of methods of estimating cointegrating relationships. In Hargreaves, C. (ed.), Nonstationary Time Series and Cointegration, pp. 87132. Oxford: Oxford University Press.Google Scholar
Hendry, D.F. (1987) Econometric methodology: A personal perspective. In Bewley, T. (ed.), Advances in Econometrics, vol. 2, pp. 2948. Cambridge: Cambridge University Press.CrossRefGoogle Scholar
Johansen, S. (1988) Statistical analysis of cointegration vectors. Journal of Economic Dynamics and Control 12, 231254.CrossRefGoogle Scholar
Johansen, S. (1991) Estimation and hypothesis testing of cointegration vectors in Gaussian vector autoregressive models. Econometrica 59, 15511580.CrossRefGoogle Scholar
Johansen, S. (1992) A representation of vector autoregressive processes integrated of order 2. Econometric Theory 8, 188202.CrossRefGoogle Scholar
Johansen, S. (1995) A statistical analysis of cointegration for I(2) variables. Econometric Theory 11, 2559.CrossRefGoogle Scholar
King, R.G., Plosser, C.I., Stock, J.H., & Watson, M.W. (1991) Stochastic trends and economic fluctuations. American Economic Review 81, 819840.Google Scholar
Kitamura, Y. (1995) Estimation of cointegrated systems with 1(2) processes. Econometric Theory 11, 124.CrossRefGoogle Scholar
Kitamura, Y. & Phillips, P.C.B. (1992) Fully Modified IV, GIVE, and GMM Estimation with Possibly Nonstationary Regressors and Instruments. Mimeo, Yale University.Google Scholar
Park, J.Y. (1992) Canonical cointegrating regressions. Econometrica 60, 119143.CrossRefGoogle Scholar
Park, J.Y. & Phillips, P.C.B. (1988) Statistical inference in regressions with integrated processes: Part 1. Econometric Theory 4, 468497.CrossRefGoogle Scholar
Park, J.Y. & Phillips, P.C.B. (1989) Statistical inference in regressions with integrated processes: Part 2. Econometric Theory 5, 95131.CrossRefGoogle Scholar
Parzen, E. (1957) On consistent estimates of the spectrum of a stationary time series. Annals of Mathematical Statistics 28, 329348.CrossRefGoogle Scholar
Phillips, P.C.B. (1986) Understanding spurious regressions in econometrics. Journal of Econometrics 33, 322340.CrossRefGoogle Scholar
Phillips, P.C.B. (1991a) Optimal inference in cointegrated systems. Econometrica 59, 283306.CrossRefGoogle Scholar
Phillips, P.C.B. (1991b) Spectral regression for cointegrated time series. In Barnett, W., Powell, J., & Tauchen, G. (eds.), Nonparametric and Semiparameteric Methods in Econometrics and Statistics, pp. 413436. Cambridge: Cambridge University Press.Google Scholar
Phillips, P.C.B. (1995) Fully modified least squares and vector autoregression. Econometrica 63, 10231078.CrossRefGoogle Scholar
Phillips, P.C.B. & Chang, Y. (1994) Fully modified least squares in I(2) regression. Econometric Theory 10, 967.Google Scholar
Phillips, P.C.B. & Durlauf, S.N. (1986) Multiple time series with integrated variables. Review of Economic Studies 53, 473496.CrossRefGoogle Scholar
Phillips, P.C.B. & Hansen, B.E. (1990) Statistical inference in instrumental variables regressions with I(1) processes. Review of Economic Studies 57, 99125.CrossRefGoogle Scholar
Phillips, P.C.B. & Loretan, M. (1991) Estimating long-run equilibria. Review of Economic Studies 59, 407436.CrossRefGoogle Scholar
Phillips, P.C.B. & Solo, V. (1992) Asymptotics for linear processes. Annals of Statistics 20, 9711001.CrossRefGoogle Scholar
Priestley, M.B. (1981) Spectral Analysis and Time Series, vols. I and II. New York: Academic Press.Google Scholar
Saikkonen, P. (1992) Estimation of Cointegration Vectors with Linear Restrictions. Mimeo, University of Helsinki.Google Scholar
Stock, J.H. & Watson, M.W. (1993) A simple estimator of cointegrating vectors in higher order integrated systems. Econometrica 61, 783820.CrossRefGoogle Scholar