A method for generating simulated plasmodes and artificial test clusters with user-defined shape, size, and orientation

We present a simple method for generating simulated plasmodes and artificia l test clusters with user-defined shape, size, and orientation. Our method differs from other cluster generation techniques in that it focuses on the validity of the duster indicators. For J clusters, indicator validity is de fined as the squared correlation ratio between the cluster indicator (i.e., the observed variable) and J-1 dummy variables. The within-cluster correla tion structure and the univariate distributions of the cluster indicators a re specified with procedures outlined by Fleishman (1978) and Vale and Maur elli (1983). Simulation results illustrate the utility of the method for cl uster analysis evaluation research.