Spatially weighted principal component analysis (PCA) method for water quality analysis

Incorporating spatial information data into the principal component analysis is of importance. Some proposed methods of spatial weighting schemes to be applied to the ordinary PCA are reviewed and a new version of the method is proposed in the context of spatial analysis for geospatial multivariate analysis. In view of spatial variations in the hydrochemistry of rivers such combined version of the technique might be useful for reliable estimates.