I\'m looking for the fastest algorithm for grouping points on a map into equally sized groups, by distance. The k-means clustering algorithm looks straightforward and promis
May I humbly suggest that you try this project ekmeans.
A Java K-means Clustering implementation with an optional special equal option that apply an equal cardinality constraint on the clusters while remaining as spatially cohesive as possible.
It is yet experimental, so just be aware of the known bugs.