It is useful in the case of heteroscedacity - anomalies in variability. This helps to discover trends in mean and variance. 3Plot software includes a moving window statistics algorithm for different choices of local areas. Considering overlapped windows is a good compromise to have representative statistics with enough samples and to keep small window for local details. Structural Analysis Structural analysis is an essential step in geostatistical approach.
Structural analysis includes trend analysis and variography.
Most of environmental data contains spatial trend due to large scale physical process. The is discovered trend in CS137 and SR90 distribution in some directions. Second-order moments describe spatial continuity and characterise spatial correlation between samples. A huge variety of second-order moments is presented in this section. Variography results in building a valid variogram model for further use in geostatistical predictors.