Hostname: page-component-8448b6f56d-t5pn6 Total loading time: 0 Render date: 2024-04-19T19:59:08.561Z Has data issue: false hasContentIssue false

MODELING NONSTATIONARY AND LEPTOKURTIC FINANCIAL TIME SERIES

Published online by Cambridge University Press:  14 October 2014

Ying Chen*
Affiliation:
National University of Singapore
Vladimir Spokoiny
Affiliation:
Weierstrass-Institute and Moscow Institute of Physics and Technology
*
*Address correspondence to Ying Chen. Department of Statistics & Applied Probability. National University of Singapore; e-mail: stacheny@nus.edu.sg.

Abstract

Financial time series is often assumed to be stationary and has a normal distribution in the literature. Both assumptions are however unrealistic. This paper proposes a new methodology with a focus on volatility estimation that is able to account for nonstationarity and heavy tails simultaneously. In particular, a local exponential smoothing (LES) approach is developed, in which weak estimates with different memory parameters are aggregated in a locally adaptive way. The procedure is fully automatic and the parameters are tuned by a new propagation approach. The extensive and practically oriented numerical results confirm the desired properties of the constructed estimate: it performs stable in a nearly time homogeneous situation and is sensitive to structural shifts. Our main theoretical “oracle” result claims that the aggregated estimate performs as good as the best estimate in the considered family. The results are stated under realistic and unrestrictive assumptions on the model.

Type
ARTICLES
Copyright
Copyright © Cambridge University Press 2014 

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.)

Footnotes

This research was supported by the NUS FRC grant R-155-000-117-112. Vladimir Spokoiny is partially supported by Laboratory for Structural Methods of Data Analysis in Predictive Modeling, MIPT, RF government grant, ag. 11.G34.31.0073. Financial support by the German Research Foundation (DFG) through the Collaborative Research Center 649 “Economic Risk” is gratefully acknowledged.

References

REFERENCES

Andreou, E. & Ghysels, E. (2002) Detecting multiple breaks in financial market volatility dynamics. Journal of Applied Econometrics 17, 579600.CrossRefGoogle Scholar
Baillie, R.T., Bollerslev, T., & Mikkelsen, H.Q. (1996) Fractionally integrated generalized autoregressive conditional heteroskedasticity. Journal of Econometrics 74, 330.CrossRefGoogle Scholar
Barndorff-Nielsen, O. (1997) Normal inverse Gaussian distributions and stochastic volatility modelling. Scandinavian Journal of Statistics 24, 113.CrossRefGoogle Scholar
Belomestny, D. & Spokoiny, V. (2007) Spatial aggregation of local likelihood estimates with applications to classification. Annals of Statistics 35, 22872311.Google Scholar
Bollerslev, T. (1986) Generalized autoregressive conditional heteroskedasticity. Journal of Econometrics 31, 307327.Google Scholar
Box, G. & Cox, D. (1964) An analysis of transformations. Journal of the Royal Statistical Society, Series B 26, 211252.Google Scholar
Cai, Z., Fan, J., & Li, R. (2000) Efficient estimation and inference for varying coefficients models. Journal of the American Statistical Association 95, 888902.Google Scholar
Chen, Y., Härdle, W., & Jeong, S.-O. (2008) Nonparametric risk management with generalized hyperbolic distributions. Journal of the American Statistical Association 103(483), 910923.CrossRefGoogle Scholar
Čížek, P., Härdle, W., & Spokoiny, V. (2009) Statistical inference for time-inhomogeneous volatility models. Econometrics Journal 12, 248271.Google Scholar
Dahlhaus, R. & Rao, S.S. (2006) Statistical inference for time-varying ARCH processes. Annals of Statistics 34, 10751114.CrossRefGoogle Scholar
Diebold, F.X. & Inoue, A. (2001) Long memory and regime switching. Journal of Econometrics 105, 131159.CrossRefGoogle Scholar
Elliott, G. & Timmermann, A. (2005) Optimal forecast combination under regime switching. International Economic Review 46, 10811102.CrossRefGoogle Scholar
Engle, R. (1982) Autoregressive conditional heteroscedasticity with estimates of the variance of UK inflation. Econometrica 50, 9871008.CrossRefGoogle Scholar
Engle, R.F. & Rangel, J.G. (2008) The spline-GARCH model for low-frequency volatility and its global macroeconomic causes. Review of Financial Studies 21, 11871222.CrossRefGoogle Scholar
Fan, J. & Zhang, W. (2008) Statistical methods with varying coefficient models. Statistics and Its Interface 1, 179195.Google ScholarPubMed
Francq, C., Lepage, G., & Zakoïan, J.-M. (2011) Two-stage non Gaussian QML estimation of GARCH models and testing the efficiency of the Gaussian QMLE. Journal of Econometrics 165, 246257.CrossRefGoogle Scholar
Granger, C.W.J. (1980) Long memory relationships and the aggregation of dynamic models. Journal of Econometrics 14, 227238.CrossRefGoogle Scholar
Granger, C.W.J. & Hyung, N. (2004) Occasional structural breaks and long memory with an application to the S&P 500 absolute stock returns. Journal of Empirical Finance 11, 399421.Google Scholar
Granger, C.W. & Joyeux, R. (1980) An introduction to long memory time series models and fractional differencing. Journal of Time Series Analysis 1, 539.Google Scholar
Hastie, T. & Tibshirani, R. (1993) Varying-coefficient models (with discussion). Journal of the Royal Statistical Society, Series B 55, 757796.Google Scholar
Hosking, J.R.M. (1981) Fractional differencing. Biometrika 68, 165176.CrossRefGoogle Scholar
Mercurio, D. & Spokoiny, V. (2004) Statistical inference for time inhomogeneous volatility models. Annals of Statistics 32, 577602.Google Scholar
Mikosch, T. & Stărică, C. (2004) Non-stationarities in financial time series, the long range dependence and the IGARCH effects. Review of Economics and Statistics 86, 378390.Google Scholar
Polzehl, J. & Spokoiny, V. (2006) Propagation-separation approach for local likelihood estimation. Probability Theory and Related Fields 135, 335362.CrossRefGoogle Scholar
Spokoiny, V. (2009) Multiscale local change point detection with applications to value-at-risk. Annals of Statistics 37(3), 14051436.CrossRefGoogle Scholar