GeoOutlier: Spatio (temporal) outliers detection

In GeoModels: Procedures for Gaussian and Non Gaussian Geostatistical (Large) Data Analysis

Spatio (temporal) outliers detection

Description

Given a set of spatio (temporal) locations and data, the procedure select the spatial or spatiotemporal ouliers using a specific algorithm.

Usage

GeoOutlier(data, coordx, coordy=NULL,coordz=NULL, coordt=NULL, coordx_dyn=NULL, 
 distance="Eucl", grid=FALSE, neighb=10,alpha=0.001,
 method="Z-Median", radius=1, bivariate=FALSE,X=NULL)

Arguments

data	An optional d-dimensional vector (a single spatial realisation) or a (d \times d)-matrix (a single spatial realisation on regular grid) or a (t \times d)-matrix (a single spatio-temporal realisation) or an (d \times d \times t \times n )-array (a single spatio-temporal realisation on regular grid).
coordx	A numeric (d \times 2)-matrix or (d \times 3)-matrix Coordinates on a sphere for a fixed radius radius are passed in lon/lat format expressed in decimal degrees.
coordy	A numeric vector giving 1-dimension of spatial coordinates; Optional argument, the default is NULL.
coordz	A numeric vector giving 1-dimension of spatial coordinates; Optional argument, the default is NULL.
coordt	A numeric vector giving 1-dimension of temporal coordinates. Optional argument, the default is NULL then a spatial RF is expected.
coordx_dyn	A list of m numeric (d_t \times 2)-matrices containing dynamical (in time) spatial coordinates. Optional argument, the default is NULL
distance	String; the name of the spatial distance. The default is Eucl, the Euclidean distance. See GeoFit for details.
grid	Logical; if FALSE (the default) the data are interpreted as spatial or spatio-temporal realisations on a set of non-equispaced spatial sites (irregular grid).
neighb	Numeric; an optional positive integer indicating the order of neighborhoodused for Z-Median algorithm.
alpha	Numeric; a numeric value between 0 and 1 used for Z-Median algorithm.
method	String; The name of the algorithm for detecting spatial ouliers. Default is Z-median proposed in Chen et al. (2008)
radius	Numeric; a value indicating the radius of the sphere when using the great circle distance. Default value is 1.
bivariate	If TRUE then data is considered as spatial bivariate data.
X	Numeric; an optional Matrix of spatio (temporal) covariates.

Value

Return a matrix or a list containing the dected spatial or spatio-temporal outliers

Author(s)

Moreno Bevilacqua, [e-mail],https://sites.google.com/view/moreno-bevilacqua/home, Víctor Morales Oñate, [e-mail], https://sites.google.com/site/moralesonatevictor/, Christian Caamaño-Carrillo, [e-mail],https://www.researchgate.net/profile/Christian-Caamano

References

Chen D, Lu C, Kou Y, Chen F (2008) On detecting spatial outliers. Geoinformatica 12:455–475

Bevilacqua M., Caamaño C., Arellano-Valle R. B., Camilo Gomez C. (2022) A class of random fields with two-piece marginal distributions for modeling point-referenced data with spatial outliers. Test 10.1007/s11749-021-00797-5

GeoModels documentation built on July 29, 2026, 5:06 p.m.