A GIS-Based Spatial-Multivariate Statistical Analysis of Water Quality Data in the Porsuk River, Turkey

ed through use from the particular to the general class or type. Hierarchical agglomerative clustering is the most common approach, which provides intuitive similarity relationships between any one sample and the entire dataset, and is typically illustrated by a dendrogram (tree diagram) (Einax et al. 1998; McKenna 2003). The dendrogram provides a visual summary of the clustering processes, presenting a picture of the groups and their proximity, with a dramatic reduction in dimensionality of the original data. The Euclidean distance usually gives the similarity between two samples, and a distance can be represented by the difference between analytical values from the samples (Otto 1998). The Ward’s method uses an analysis of variance approach to evaluate the distances between clusters in an attempt to minimize the sum of squares of any two clusters that can be formed at