Clusters and Densities Do features cluster and at what distance? Ripley’s K (ArcMap) Plotting Sum of Squares ® Where are the clusters? K-Means clustering (R) Density surfaces Kernel Density Methods Hierarchical Methods Dendrograms
Spatial Cluster Analysis Wikipedia
Ripley’s K Measure of spatial homogeneity http://www.stat.iastate.edu/preprint/articles/2001-18.pdf
L(d) Expected: for random data Observed: k drives the model k = 1 when distance from i to j < d k = 0 when distance from i to j >=d
Ripley’s K Counts the number of points within a distance of each other
Cluster Analysis ArcGIS Help
Ripley’s K - ArcGIS ArcGIS Help
Ripley’s K Small circles have no points within distance
Ripley’s K At the right distance, we have more points within the distance than expected
Ripley’s K At large distances, we include the expected number of points.
Random Data
Multi-Distance Cluster Analysis