Identifiablility for Non-Stationary Spatial Structure
نویسندگان
چکیده
For modelling non-stationary spatial random fields Z = {Z(x) : x ∈ Rn, n ≥ 2} a recent method has been proposed to deform bijectively the index space so that the spatial dispersion D(x, y) = var[Z(x) − Z(y)], (x, y) ∈ Rn × Rn, depends only on the Euclidean distance in the deformed space through a stationary and isotropic variogram γ. We prove uniqueness of this model in two different cases: (i) γ is strictly increasing; (ii) γ(u) is differentiable for u > 0. BIJECTIVE SPACE DEFORMATION; DISPERSION FUNCTION; ISOTROPY; STATIONARITY; UNIQUENESS; VARIOGRAM AMS 1991 SUBJECT CLASSIFICATION: PRIMARY 60G60 SECONDARY 60G12
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