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Saddlepoint approximation to the distribution of the total distance of the continuous time random walk

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Abstract

This article considers the random walk over Rp, with p ≥ 2, where a given particle starts at the origin and moves stepwise with uniformly distributed step directions and step lengths following a common distribution. Step directions and step lengths are independent. The case where the number of steps of the particle is fixed and the more general case where it follows an independent continuous time inhomogeneous counting process are considered. Saddlepoint approximations to the distribution of the distance from the position of the particle to the origin are provided. Despite the p-dimensional nature of the random walk, the computations of the saddlepoint approximations are one-dimensional and thus simple. Explicit formulae are derived with dimension p = 3: for uniformly and exponentially distributed step lengths, for fixed and for Poisson distributed number of steps. In these situations, the high accuracy of the saddlepoint approximations is illustrated by numerical comparisons with Monte Carlo simulation.

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References

  1. U. Shmueli, G.H. Weiss, in Introduction to crystallographic statistics, International Union of Crystallography book series (Oxford University Press, New York, 1995), Vol. 6

  2. K. Pearson, Nature 72, 294 (1905)

    Article  ADS  Google Scholar 

  3. R. Metzler, J. Klafter, Phys. Rep. 339, 1 (2000)

    Article  ADS  Google Scholar 

  4. J.B. Perrin, Ann. Chim. Phys. 18, 1 (1909)

    Google Scholar 

  5. J.C. Kluyver, Ned. Akad. Wet. Proc. Ser. A 8, 341 (1906)

    ADS  Google Scholar 

  6. L. Rayleigh, Philos. Mag. 37, 321 (1919)

    Article  Google Scholar 

  7. R. Barakat, J. Phys. A: Math. Nucl. Gen. 6, 796 (1973)

    Article  ADS  Google Scholar 

  8. E. Orsingher, A. De Gregorio, J. Theor. Probab. 20, 769 (2007)

    Article  Google Scholar 

  9. W. Stadje, J. Stat. Phys. 56, 415 (1989)

    Article  ADS  Google Scholar 

  10. M. Masoliver, J.M. Porrá, G.H. Weiss, Physica A 193, 469 (1993)

    Article  ADS  Google Scholar 

  11. J.L. Jensen, Saddlepoint approximations (Oxford University Press, New York, 1995)

  12. R. Gatto, Methodol. Comput. Appl. Probab. 19, 843 (2017)

    Article  MathSciNet  Google Scholar 

  13. G.H. Weiss, J.E. Kiefer, J. Phys. A: Math. Gen. 16, 489 (1983)

    Article  ADS  Google Scholar 

  14. R. Gatto, M. Mayer, Stat. Methodol. 2, 233 (2005)

    Article  MathSciNet  Google Scholar 

  15. R. Gatto, S.R. Jammalamadaka, Sankhyā A: Math. Stat. Probab. 65, 333 (2003)

    Google Scholar 

  16. R. Gatto, Math. Methods Stat. 26, 20 (2017)

    Article  Google Scholar 

  17. E.T. Copson, Asymptotic expansions (Cambridge University Press, Cambridge, 1965)

  18. N.G. De Bruijn, Asymptotic methods in analysis (Dover Publications, New York, 1982) (reprint)

  19. N. Bleistein, R.A. Handelsman, Asymptotic expansions of integrals (Dover Publications, New York, 1986) (reprint)

  20. H.E. Daniels, Ann. Math. Stat. 25, 631 (1954)

    Article  Google Scholar 

  21. O.E. Barndorff-Nielsen, D.R. Cox, Asymptotic techniques for use in statistics (Chapman & Hall, New York, 1989)

  22. G.H. Weiss, Aspects and applications of the random walk (North Holland Press, Amsterdam, 1994)

  23. R. Gatto, Saddlepoint approximations, in StatsRef: statistics reference online, edited by Balakrishnan et al. (Wiley and Sons, 2015), pp. 1–7 [Update based on original article by G.H. Weiss, doi:10.1002/9781118445112.stat01796.pub2]

  24. G. Watson, Statistics on spheres, University of Arkansas lecture notes in the mathematical sciences (Wiley and Sons, New York, 1983)

  25. K.V. Mardia, P.E. Jupp, Directional statistics (Wiley and Sons, Chichester, 2000)

  26. M. Abramowitz, I.E. Stegun, Handbook of mathematical functions with formulas, graphs, and mathematical tables (Dover Publications, New York, 1972) (reprint)

  27. C.A. Field, E. Ronchetti, in Small sample asymptotics, Institute of Mathematical Statistics lecturenotes – monograph series (Hayward, California, 1990), Vol. 13

  28. R. Lugannani, S. Rice, Adv. Appl. Probab. 12, 475 (1980)

    Article  Google Scholar 

  29. E.W. Montroll, G.H. Weiss, J. Math. Phys. 6, 167 (1965)

    Article  ADS  Google Scholar 

  30. J.-P. Bouchaud, A. Georges, Phys. Rep. 195, 127 (1990)

    Article  ADS  MathSciNet  Google Scholar 

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Correspondence to Riccardo Gatto.

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Contribution to the “Topical Issue: Continuous Time Random Walk Still Trendy: Fifty-year History, Current State and Outlook”, edited by Ryszard Kutner and Jaume Masoliver.

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Gatto, R. Saddlepoint approximation to the distribution of the total distance of the continuous time random walk. Eur. Phys. J. B 90, 238 (2017). https://doi.org/10.1140/epjb/e2017-80228-y

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  • DOI: https://doi.org/10.1140/epjb/e2017-80228-y

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