Proposal of the spatial dependence evaluation from the power semivariogram model

In Geostatistics, the use of measurement to describe the spatial dependence of the attribute is of great importance, but only some models (which have second-order stationarity) are considered with such measurement. Thus, this paper aims to propose measurements to assess the degree of spatial depende...

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Detalles Bibliográficos
Autores: Barbosa, Ismael Canabarro, Appel Neto, Edemar, Seidel, Enio Júnior, Oliveira, Marcelo Silva de
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2017
País:Brasil
Institución:Universidade Federal de Lavras (UFLA)
Repositorio:Repositório Institucional da UFLA
Idioma:inglés
OAI Identifier:oai:repositorio.ufla.br:1/37002
Acceso en línea:https://repositorio.ufla.br/handle/1/37002
Access Level:acceso abierto
Palabra clave:Geostatistics
Variographic analysis
Semivariogram model
Spatial dependence indexes
Geoestatística
Análise variográfica
Modelo de semivariograma
Índices de dependência espacial
Descripción
Sumario:In Geostatistics, the use of measurement to describe the spatial dependence of the attribute is of great importance, but only some models (which have second-order stationarity) are considered with such measurement. Thus, this paper aims to propose measurements to assess the degree of spatial dependence in power model adjustment phenomena. From a premise that considers the equivalent sill as the estimated semivariance value that matches the point where the adjusted power model curves intersect, it is possible to build two indexes to evaluate such dependence. The first one, SPD * , is obtained from the relation between the equivalent contribution (α) and the equivalent sill (C * = C 0 + α), and varies from 0 to 100% (based on the calculation of spatial dependence areas). The second one, SDI * , beyond the previous relation, considers the equivalent factor of model (FM * ), which depends on the exponent β that describes the force of spatial dependence in the power model (based on spatial correlation areas). The SDI * ,for β close to 2, assumes its larger scale, varying from 0 to 66.67%. Both indexes have symmetrical distribution, and allow the classification of spatial dependence in weak, moderate and strong.