A general method for two-mode simultaneous reduction of units and variables of a data matrix is introduced. It consists in a convex linear combination of Reduced K-Means (RKM) and Factorial K-Means (FKM). Both methodologies involve principal component analysis for variables and K-Means for units, even though RKM aims at maximizing the between-clusters deviance without imposing any condition on the within-clusters deviance, while FKM aims at minimizing the within-clusters deviance without imposing any condition on the between one. It follows that RKM and FKM complement each other. In order to take advantage of both methods a convex linear combination of RKM and FKM is proposed. Furthermore, the fuzzy approach to clustering is adopted because of its flexibility in handling the real world complexity and uncertainty. A fast Alternating Least Squares algorithm is introduced and its performance is investigated by simulated and real data.
A general method for fuzzy partitioning and component analysis / Ferraro, MARIA BRIGIDA; Giordani, Paolo; Vichi, Maurizio. - (2015), pp. 249-249. (Intervento presentato al convegno The 2015 conference of the International Federation of Classification Societies tenutosi a Bologna nel 6-8 July 2015).
A general method for fuzzy partitioning and component analysis
FERRARO, MARIA BRIGIDA;GIORDANI, Paolo;VICHI, Maurizio
2015
Abstract
A general method for two-mode simultaneous reduction of units and variables of a data matrix is introduced. It consists in a convex linear combination of Reduced K-Means (RKM) and Factorial K-Means (FKM). Both methodologies involve principal component analysis for variables and K-Means for units, even though RKM aims at maximizing the between-clusters deviance without imposing any condition on the within-clusters deviance, while FKM aims at minimizing the within-clusters deviance without imposing any condition on the between one. It follows that RKM and FKM complement each other. In order to take advantage of both methods a convex linear combination of RKM and FKM is proposed. Furthermore, the fuzzy approach to clustering is adopted because of its flexibility in handling the real world complexity and uncertainty. A fast Alternating Least Squares algorithm is introduced and its performance is investigated by simulated and real data.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.