This page serves as a repository of software and source files developed by staff and students associated with the M&T group


Hierarchical cluster analysis as implemented in most of the well known statistical computer programs neglects the phenomenon of input order instability. That is, cluster solutions may differ when the rows and colums of the proximity matrix are permuted. This phenomenon is not widely known and is caused by ties that are present in the initial (dis)similarity matrix or arise during the process of clustering. To tackle this phenomenon, PermuCLUSTER has been developed.

PermuCLUSTER repeats the analysis a large number of times by permuting the rows and columns of the proximity matrix. In order to compare the solutions and find the optimal solution, a goodness-of-fit measure is used. The number of times the matrix should be permuted is variable and is user defined. PermuCLUSTER is an SPSS add-in and offers all but the same functionality as CLUSTER in SPSS.

Constrained singular value decompositions for multiple tables

MATLAB m-files to analyse three-way data and a short description.txt file are provided. Each slice of the three way box is decomposed by a singular value decomposition. The singular values or vectors may be constrained to be equal over the slices.

The procedure is described in De Rooij, M. and Anderson, CJ. Visualizing, Summarizing, and Comparing odds ratio structures. Manuscript under revision.

Last Modified: 05-06-2007