Title: Fuzzy two-mode clustering: How to determine the optimal number of clusters Authors:  Maria Brigida Ferraro - Sapienza University of Rome (Italy) [presenting]
Paolo Giordani - Sapienza University of Rome (Italy)
Maurizio Vichi - University La Sapienza, Rome (Italy)
Abstract: Two-mode clustering consists of simultaneously grouping rows and columns of an observed data matrix. In this context, one of the open problems is determining the optimal number of clusters of both partitions. The choice must take into account the overall compactness and separation of the two-mode partition. In addition, if a fuzzy approach to clustering is adopted, the two membership degree matrices should assist in this task. For this reason, some cluster validity indices are introduced and investigated, considering the dual objective and the partition's fuzziness. The adequacy of the proposed indices is checked by means of some simulated datasets.