×

VARIOWIN. Software for spatial data analysis in 2D. (English) Zbl 0855.65149

Statistics and Computing (Cham). New York, NY: Springer. ix, 91 p. (1996).
VARIOWIN is a collection of four Windows programs – Prevar2D, Vario2D with PCF, Model and Grid Display – that are used for spatial data analysis and variogram modelling of irregularly spaced data in two dimensions. Prevar2D builds a pair comparison file (PCF), that is, a binary file containing pairs of data sorted in terms of increasing distance. Pair comparison files can be built from subsets in order to reduce memory requirements. Vario2D with PCF is used for spatial data analysis of 2D data. It uses an ASCII file and a binary pair comparison file produced by Prevar2D. Features implemented in Vario2D with PCF include:
– the possibility to characterize the spatial continuity of one variable or the joined spatial continuity of two variables;
– variogram surfaces for identifying directions of anisotropies;
– directional variograms calculated along any direction;
– several measures of spatial continuity (Not only the variogram but also the standardized variogram, the covariance, the correlogram, and the madogram are used to measure spatial continuity.)
– \(h\)-scatterplots to assess the meaning of measures;
– the identification and localization of pairs of data adversely affecting the measure of spatial continuity (Once identified, these pairs can be masked from the calculation interactively.);
– variogram clouds for identifying pairs of data values having the most influence on the measure of spatial continuity (Those pairs can also be located on the sample map.);
– the ability to save directional variograms in an ASCII file that can be used for subsequent modelling by the Model program.
The Model program is used to produce a 2D nested model of spatial continuity in an interactive way. Several directional variograms read from a variogram file produced by Vario2D with PCF are adjusted simultaneously by a 2D nested model. The adjustment is done with scroll bars. Each time a parameter of the 2D model is changed, cross sections through the 2D model are recalculated and redrawn on the experimental variograms used for the fitting procedure. The 2D nested model can be saved in a model file that is used to store the various parameters required for geostatical estimation – kriging – or simulation.
Grid display is used for producing pixel maps of experimental and modeled variogram surfaces that have previously been saved into grid files. Experimental and modeled variogram surfaces can now be compared on-screen. Aside, that, the program offers:
– the capacity to copy to the clipboard all plots produced by Vario2D with PCF, Model, and Grid Display ( (Those plots can be copied as bitmaps or as a collection of objects using the Windows metafile format.);
– Install and Uninstall utilities that make it very easy to install/uninstall VARIOWIN under Windows 3.x, 95 and NT;
– a completely revised user guide that replaces the on-line help.
The book is developed for teaching purposes. The fundamentals of spatial data analysis and of geostatics are recalled and some suggestions on what to do and what to avoid when using the software for a geostatistical study are given.
Reviewer: J.Antoch (Praha)

MSC:

65C99 Probabilistic methods, stochastic differential equations
62-07 Data analysis (statistics) (MSC2010)
65-02 Research exposition (monographs, survey articles) pertaining to numerical analysis
62-04 Software, source code, etc. for problems pertaining to statistics

Software:

VARIOWIN
PDFBibTeX XMLCite