A crossinggram for random fields on lattices

Helena Ferreira; Marta Ferreira; Luís A. Alexandre

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arXiv · 1906.10923

A crossinggram for random fields on lattices

Helena Ferreira·Marta Ferreira·Luís A. Alexandre

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Abstract

The modeling of risk situations that occur in a space-time framework can be done using max-stable random fields on lattices. Although the summary coefficients for the spatial and temporal behaviour do not characterize the finite-dimensional distributions of the random field, they have the advantage of being immediate to interpret and easier to estimate. The coefficients that we propose give us information about the tendency of a random field for local oscillations of its values in relation to real valued high levels. It is not the magnitude of the oscillations that is being evaluated, but rather the greater or lesser number of oscillations, that is, the tendency of the trajectories to oscillate. We can observe surface trajectories more smooth over a region according to higher crossinggram value. It takes value in $[0,1]$ and increases with the concordance of the variables of the random field.

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Helena Ferreira, Marta Ferreira, Luís A. Alexandre. 2019-06-26. A crossinggram for random fields on lattices. https://arxiv.org/abs/1906.10923

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