Source: Ann. Statist. Volume 32, Number 2
(2004), 656-692.
Asymptotic properties of the local Whittle estimator in the nonstationary case (d>½) are explored. For ½<d≤1, the estimator is shown to be consistent, and its limit distribution and the rate of convergence depend on the value of d. For d=1, the limit distribution is mixed normal. For d>1 and when the process has a polynomial trend of order α>½, the estimator is shown to be inconsistent and to converge in probability to unity.
References
Andrews, D. W. K. and Sun, Y. (2001). Local polynomial Whittle estimation of long-range dependence. Discussion Paper 1293, Cowles Foundation, Yale Univ. Available at cowles.econ.yale.edu.
Corbae, D., Ouliaris, S. and Phillips, P. C. B. (2002). Band spectral regression with trending data. Econometrica 70 1067--1109.
Erdélyi, A., ed. (1953). Higher Transcendental Functions 1. Krieger, Malabar, FL.
Gray, H. L., Zhang, N.-F. and Woodward, W. A. (1989). On generalized fractional processes. J. Time Ser. Anal. 10 233--257.
Hall, P. and Heyde, C. C. (1980). Martingale Limit Theory and Its Application. Academic Press, New York.
Mathematical Reviews (MathSciNet):
MR624435
Hurvich, C. M. and Chen, W. W. (2000). An efficient taper for potentially overdifferenced long-memory time series. J. Time Ser. Anal. 21 155--180.
Kim, C. S. and Phillips, P. C. B. (1999). Log periodogram regression: The nonstationary case. Mimeograph, Cowles Foundation, Yale Univ.
Künsch, H. (1987). Statistical aspects of self-similar processes. In Proc. First World Congress of the Bernoulli Society (Yu. Prokhorov and V. V. Sazanov, eds.) 1 67--74. VNU Science Press, Utrecht.
Marinucci, D. and Robinson, P. M. (2000). Weak convergence of multivariate fractional processes. Stochastic Process. Appl. 86 103--120.
Nelson, C. R. and Plosser, C. I. (1982). Trends and random walks in macroeconomic time series: Some evidence and implications. J. Monetary Economics 10 139--162.
Phillips, P. C. B. (1999a). Discrete Fourier transforms of fractional processes. Discussion Paper 1243, Cowles Foundation, Yale Univ. Available at cowles.econ.yale.edu.
Phillips, P. C. B. (1999b). Unit root log periodogram regression. Discussion Paper 1244, Cowles Foundation, Yale University. Available at cowles.econ.yale.edu.
Robinson, P. M. (1995). Gaussian semiparametric estimation of long range dependence. Ann. Statist. 23 1630--1661.
Robinson, P. M. and Marinucci, D. (2001). Narrow-band analysis of nonstationary processes. Ann. Statist. 29 947--986.
Schotman, P. and van Dijk, H. K. (1991). On Bayesian routes to unit roots. J. Appl. Econometrics 6 387--401.
Shimotsu, K. and Phillips, P. C. B. (2002). Exact local Whittle estimation of fractional integration. Discussion Paper 1367, Cowles Foundation, Yale Univ. Available at cowles.econ.yale.edu.
Velasco, C. (1999). Gaussian semiparametric estimation of non-stationary time series. J. Time Ser. Anal. 20 87--127.
Zygmund, A. (1959). Trigonometric Series, 2nd ed. Cambridge Univ. Press.
Mathematical Reviews (MathSciNet):
MR107776