F. Giménez-Palomares1, J.A. Monsoriu-Serra1, J.Q. Cuador-Gil2

1Universitat Politècnica de Valencia (SPAIN)
2Universidad de Pinar del Rio (CUBA)
A experimental semivariogram allows to describe the spatial variability of a phenomenon of interest and analyzes the influence of data at different distances. Although it provides enough information about the behavior of a variable, it is necessary to make an adjustment to theoretical models to quantify the degree and scale of spatial variation. This setting provides a number of parameters such as range, nugget effect, sill, range, anisotropy angle, etc. that are indispensable in Geostatistics. Some of the most commonly used models are the nugget effect, spherical, exponential, Gaussian and power function. In this paper we show two computer applications, implemented as graphical user interfaces of Matlab, which can obtain the corresponding semivariogram to a spatial data set and its manual or automatic adjustment to any of the most used official models. In the case of automatic adjustment has been used the least squares method.