Minimum spanning tree: ordering edges to identify clustering structure

Abstract Ordering edges to identify clustering structure (OETICS), the clustering algorithm presented here, is based on the minimum spanning tree connecting the objects. The edges of the tree are ordered, beginning from the longest edge, to form groups of objects separated by large edges. The plot of ordered edges is the main result of the algorithm. In some aspects OETICS is similar to OPTICS, a known clustering technique that orders the objects with reference to the local density, but the solution is unique, because it does not select the value of some parameters, as the generating distance in OPTICS. OETICS is applied to many simulated and real data sets, with very different number of objects and variables, and the results are compared with those obtained by OPTICS.