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The excursions of a stationary Gaussian process outside a large two-dimensional region

Published online by Cambridge University Press:  01 July 2016

Robert Illsley*
Affiliation:
London Guildhall University
*
Current address: 2 Marble Hill Gardens, Twickenham, Middlesex, TW1 3AX, UK. Email address: robert@illsleys.freeserve.co.uk

Abstract

Let X(t) be a continuous two-dimensional stationary Gaussian process with mean zero, having a marginal density function p[x] and covariance matrix R(t). Let Δ = {∂L; L > 0} be a family of piecewise smooth boundaries of similar two-dimensional star-shaped regions ΓL. We show that, under two conditions on R(t), the asymptotic distribution of the duration of an excursion of X(t) outside ΓL, for large L, depends on the position of the maximum of p[x] on ∂L and on whether R′(0) is zero or not, should the maximum occur at a vertex. We obtain the asymptotic distributions of the duration of an excursion for each of the three cases that arise. We also generalise some results of Breitung (1994) on the asymptotic crossing rates of vector Gaussian processes.

Type
General Applied Probability
Copyright
Copyright © Applied Probability Trust 2001 

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References

Anderson, T. W. (1958). An Introduction to Multivariate Statistical Analysis. John Wiley, New York.Google Scholar
Aronowich, M. and Adler, R. J. (1986). Extrema and level crossings of χ2 processes. Adv. Appl. Prob. 18, 901920.Google Scholar
Belyaev, Yu. K. and Nosko, V. P. (1969). Characteristics of excursions above a high level for a Gaussian process and its envelope. Theory Prob. Appl. 14, 296309.Google Scholar
Berman, S. M. (1984). Sojourns of vector Gaussian processes inside and outside spheres. Z. Wahrscheinlichkeitsth. 66, 529542.Google Scholar
Breitung, K. W. (1994). Asymptotic Approximations for Probability Integrals (Lecture Notes Math. 1592). Springer, Berlin.Google Scholar
Cramér, H. and Leadbetter, M. R. (1967). Stationary and Related Stochastic Processes. John Wiley, New York.Google Scholar
Illsley, R. G. (1992). The crossings of boundaries by vector Gaussian processes with applications to problems in reliability. , City University, London.Google Scholar
Illsley, R. G. (1998). The moments of the number of exits from a simply connected region. Adv. Appl. Prob. 30, 167180.CrossRefGoogle Scholar
Kac, M. and Slepian, D. (1959). Large excursions of Gaussian processes. Ann. Math. Statist. 30, 12151228.Google Scholar
Lindgren, G. (1980a). Extreme values and crossings for the χ2-process and other functions of multidimensional Gaussian processes, with reliability applications. Adv. Appl. Prob. 12, 746774.Google Scholar
Lindgren, G. (1980b). Point processes of exits by bivariate Gaussian processes and extremal theory for the χ2-process and its concomitants. J. Multivar. Anal. 10, 181206.CrossRefGoogle Scholar
Rice, S. O. (1958). Distribution of the duration of fades in radio transmission. Bell System Tech. J. 37, 581635.CrossRefGoogle Scholar
Sharpe, K. (1978). Some properties of the crossings process generated by a stationary χ2-process. Adv. Appl. Prob. 10, 373391.Google Scholar
Volkonskii, V. A. and Rozanov, Yu. A. (1961). Some limit theorems for random functions, II. Theory Prob. Appl. 6, 186198.Google Scholar
Wong, R. (1989). Asymptotic Approximations of Integrals. Academic Press, San Diego.Google Scholar