The results of estimating the areal average climatological rainfall mean in the Guadalhorce river basin in southern Spain are presented in this paper. The classical Thiessen method and three different geostatistical approaches (ordinary kriging, cokriging and kriging with an external drift) have been used as estimators and their results are compared and discussed. The first two methods use only...

Kriging is a powerful spatial interpolation technique, especially for irregularly spaced data points, and is widely used throughout the earth and environmental sciences. The estimation at an unsampled location is given as the weighted sum of the circumjacent observed points. The weighting factors depend on a model of spatial correlation. Calculation of the weighting factors is done by minimizin...

We consider the problem of the interpolation of irregularly spaced spatial data, applied to observation of Cosmic Microwave Background (CMB) anisotropies. The well-known interpolation methods and kriging are compared to the binning method which serves as a reference approach. We analyse kriging versus binning results for different resolutions and noise level in the original data. Most of the ti...

In recent years, much work was devoted to the study of theoretical foundations of Disjunctive Logic Programs and Disjunctive Deductive Databases. While the semantics of non-disjunctive programs is fairly well understood the declarative and computational foundations of disjunctive programming proved to be much more elusive and dif-cult. Recently, two new and very promising semantics have been pr...

Nonmonotonic reasoning has been explored as a form of abductive reasoning where default assumptions are treated as abductive hypotheses. While the semantics and proof theories under this approach have been studied extensively , the question of how disjunctive programs may be used to reason abductively has rarely been investigated. At the center of the question is how to embed disjunctive reason...

This paper presents the relationship between disjunctive logic programs and default theories. We rst show that Bidoit and Froidevaux's positivist default theory causes a problem in the presence of disjunctive information in a program. Then we present a correct transformation of disjunctive logic programs into default theories and show a one-to-one correspondence between the stable models of a p...

and Salas (1985) compared kriging with several other interpolation techniques, including inverse distance, for The choice of an optimal interpolation technique for estimating annual precipitation distributions and found kriging to soil properties at unsampled locations is an important issue in sitebe superior to inverse distance weighting. Warrick et specific management. The objective of this s...

We investigate the fundamental problem of when a ground atom in a disjunctive database is assumed false. There are basically two diierent approaches for inferring negative information for disjunctive databases; they are Minker's Generalized Closed World Assumption (GCWA) and Ross and Topor's Disjunctive Database Rule (DDR). A problem with the GCWA is that disjunctive clauses are sometimes inter...