Cluster Tools
Untangling a design problem maze.

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Design MatriX utilizes cluster analysis to untangle complex design problems and generate bottom-up design strategies, the technological core of Structured Planning and a tool for the evolution of Pattern Languages. Cluster Tools is a set of tools written in the Interactive Data Language (IDL) to implement this cluster analysis process.
Interaction Matrix
Interaction Matrix Editor
zoomed out

Interaction Matrix zoomed in
Interaction Matrix Editor
zoomed in

Interaction Matrix

The process involves constructing an Interaction Matrix whose rows and columns represent design insights (otherwise variously called "misfit variables", "requirements", "problem elements", or "design factors"). Cells in the matrix (or array) indicate which design insights interact because the solutions they imply either support or conflict with each other. Typically Design MatriX produces a web page for each of these design insights for its clients, and the clusters define sets of insights that should be pondered together.

The cells may be binary (on or off), weighted with a factor of certainty, or preprocessed to generate correlation coefficients associated with each cell. The interaction matrix may be imported from an ASCII database file, generated interactively by means of a form (similar to a spreadsheet), or generated interactively using a visual interaction matrix editor.

Users can zoom the visual interaction matrix editor in and out; when zoomed in the cells are enlarged making it easy to click on a cell. When users click on a cell in the interaction matrix editor, the cell changes color to indicate whether the interaction is on or off, and since the matrix is symmetrical along the diagonal the corresponding cell also changes color. (If design insight 'x' interacts with 'y', it follows that 'y' interacts with 'x'.)


Users can at any time save the interaction matrix to a data file, reload it or another one, and update it at will. At any time users can select Cluster from the menu bar or tool bar. For any given matrix there is a maximum number of possible clusters, which is the default number, but users can specify any number of clusters up to that number. In addition, users may specify the number of iterations used to compute the cluster weights or "centers". Generally, more iterations produce cluster sets with more similar numbers of elements and connection ratios, the ratios of existing links to possible links in a set.

Cluster Set Plots
Cluster Set Plots

Cluster Weights Plot
Cluster Weights Plot

See also a simple example of Cluster Tools using an interaction matrix of 21 elements.

Cluster Set Plots

After the matrix is clustered users can select Plot Sets to plot diagrams of the cluster sets, each one based on a polygon whose vertices represent the design insights in the cluster. The visual characteristics of these diagrams are user-configurable, including the graphical layout, scale, line thickness and type (solid, dotted, dashed, etc.), font, and colors for the background, fonts and polygon lines.

Other Features

Future Enhancements

Enhancements to Cluster Tools under development include:


Cluster Tools can be adapted to your cluster analysis needs.
Specifically developed to support our own design projects, Cluster Tools is not available as an application product. However, the underlying computer code could be tailored to visualize cluster analyses of other types of data which are expressed in arrays of variables and observations or samples. In addition, these tools could be tied into other analytic tools such as correlation analysis and multivariate analysis.
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If this set of tools and the design processes they support could help your organization untangle its design problems, or if you could use such tools in other cluster analysis applications, call Design MatriX at (310) 455 3107 or