An efficient semiparametric maxima estimator of the extremal index

Abstract

The extremal index θ, a measure of the degree of local dependence in the extremes of a stationary process, plays an important role in extreme value analyses. We estimate θ semiparametrically, using the relationship between the distribution of block maxima and the marginal distribution of a process to define a semiparametric model. We show that these semiparametric estimators are simpler and substantially more efficient than their parametric counterparts. We seek to improve efficiency further using maxima over sliding blocks. A simulation study shows that the semiparametric estimators are competitive with the leading estimators. An application to sea-surge heights combines inferences about θ with a standard extreme value analysis of block maxima to estimate marginal quantiles.

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References

  1. Ancona-Navarrete, M.A., Tawn, J.A.: A comparison of methods for estimating the extremal index. Extremes 3(1), 5–38 (2000)

    MATH  MathSciNet  Article  Google Scholar 

  2. Beirlant, J., Goegebeur, Y., Segers, J., Teugels, J.: Statistics of Extremes: Theory and Applications. Wiley, Chichester (2004)

    Google Scholar 

  3. Canty, A., Ripley, B.D.: boot: Bootstrap R (S-Plus) functions, R package version 1. 3–11 (2014)

  4. Chandler, R.E., Bate, S.B.: Inference for clustered data using the independence loglikelihood. Biometrika 94(1), 167–183 (2007)

    MATH  MathSciNet  Article  Google Scholar 

  5. Chavez-Demoulin, V., Davison, A.C.: Modelling time series extremes. REVSTAT - Stat. J. 10(1), 109–133 (2012)

    MATH  MathSciNet  Google Scholar 

  6. Coles, S.G.: Modelling extreme multivariate events. PhD thesis, University of Sheffield, Sheffield, U.K. (1991)

  7. Dabrowska, D.M., Doksum, K.A., Miura, R.: Rank estimates in a class of semiparametric two-sample models. Ann. Inst. Statist. Math. 41(1), 63–79 (1989)

    MATH  MathSciNet  Google Scholar 

  8. Davis, R., Resnick, S.: Basic properties and prediction of max-ARMA processes. Adv. Appl. Prob. 21, 781–803 (1989)

    MATH  MathSciNet  Article  Google Scholar 

  9. Davison, A.C., Hinkley, D.V.: Bootstrap Methods and Their Application. Cambridge University Press, New York (1997)

    Google Scholar 

  10. Deheuvels, P.: Point processes and multivariate extreme values. J. Multivariate. Anal. 13(2), 257–272 (1983)

    MATH  MathSciNet  Article  Google Scholar 

  11. Fawcett, L., Walshaw, D.: Estimating return levels from serially dependent extremes. Environmetrics 23(3), 272–283 (2012)

    MathSciNet  Article  Google Scholar 

  12. Ferro, C.A.T., Segers, J.: Inference for clusters of extreme values. J. R. Statist. Soc. B 65(2), 545–556 (2003)

    MATH  MathSciNet  Article  Google Scholar 

  13. Ferro, C.A.T., Pezzulli, S.: Rao-Blackwellised estimators for parameters of extreme-value models http://empslocal.ex.ac.uk/people/staff/ferro/Publications/raoblackwell.pdf (2005)

  14. Gomes, M.I.: On the estimation of parameters of rare events in environmental time series. In: Barnett, V, Turkman, K (eds.) Statistics for the Environment 2: Water Related Issues, pp. 225–241. Wiley, New York (1993)

    Google Scholar 

  15. Hayfield, T., Racine, J.S.: Nonparametric econometrics: The np package. J. Stat. Softw. 27(5), 1–32 (2008)

    Article  Google Scholar 

  16. Laurini, F., Tawn, J.A.: New estimators for the extremal index and other cluster characteristics. Extremes 6, 189–211 (2003)

    MATH  MathSciNet  Article  Google Scholar 

  17. Leadbetter, M., Lindgren, G., Rootzén, H.: Extremes and related properties of random sequences and series. Springer Verlag, New York (1983)

    Google Scholar 

  18. Northrop, P.J.: Semiparametric estimation of the extremal index using block maxima. Tech. Rep. 259, University College London (2005)

  19. Patton, A., Politis, D., White, H.: Correction to Automatic block-length selection for the dependent bootstrap by D. Politis and H. White. Econ. Rev. 28(4), 372–375 (2009)

    MATH  MathSciNet  Article  Google Scholar 

  20. Politis, D., Romano, J.: The stationary bootstrap. J. Am. Statist. Ass. 89(428), 1303–1313 (1994)

    MATH  MathSciNet  Article  Google Scholar 

  21. Prescott, P., Walden, A.: Maximum likelihood estimation of the parameters of the generalized extreme value distribution. Biometrika 67(3), 723–724 (1980)

    MathSciNet  Article  Google Scholar 

  22. Robert, C.Y.: Inference for the limiting cluster size distribution of extreme values. Ann. Statist. 37(1), 271–310 (2009)

    MATH  MathSciNet  Article  Google Scholar 

  23. Robert, C.Y.: Automatic declustering of rare events. Biometrika 100(3), 587–606 (2013)

    MATH  MathSciNet  Article  Google Scholar 

  24. Robert, C.Y., Segers, J., Ferro, C.A.T.: A sliding blocks estimator for the extremal index. Electron. J. Stat. 3, 993–1020 (2009)

    MATH  MathSciNet  Article  Google Scholar 

  25. Smith, R.L.: Maximum likelihood estimation in a class of non-regular cases. Biometrika 72(1), 67–92 (1985)

    MATH  MathSciNet  Article  Google Scholar 

  26. Smith, R.L.: A theoretical comparison of the annual maximum and threshold approaches to extreme value analysis. Tech. Rep. 53, University of Surrey (1987)

  27. Smith, R.L.: The extremal index for a Markov Chain. J. App. Prob. 29(1), 37–45 (1992)

    MATH  Article  Google Scholar 

  28. Smith, R.L., Weissman, I.: Estimating the extremal index. J. R. Statist. Soc. B. 56(3), 515–528 (1994)

    MATH  MathSciNet  Google Scholar 

  29. Süveges, M.: Likelihood estimation of the extremal index. Extremes 10, 41–55 (2007)

    MATH  MathSciNet  Article  Google Scholar 

  30. Süveges, M., Davison, A.C.: Model misspecification in peaks over threshold analysis. Ann. Appl. Statist. 4(1), 203–221 (2010)

    MATH  Article  Google Scholar 

  31. White, H.: Maximum likelihood estimation of misspecified models. Econometrika 50(1), 1–25 (1982)

    MATH  Article  Google Scholar 

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Correspondence to Paul J. Northrop.

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Northrop, P.J. An efficient semiparametric maxima estimator of the extremal index. Extremes 18, 585–603 (2015). https://doi.org/10.1007/s10687-015-0221-5

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Keywords

  • Block maxima
  • Extremal index
  • Extreme value theory
  • Sea-surge heights
  • Semiparametric estimation

AMS 2000 Subject Classifications

  • 62G32
  • 62F03
  • 62F05
  • 62P12
  • 62P35