PERMAP 11.8a (PERceptual MAPping Software). PERMAP is a free, Windows-based, real-time interactive program for making perceptual maps (also called product maps, strategic maps, sociograms, sociometric maps, psychometric maps, stimulus-response maps, relationship maps, concept maps, etc.). Its fundamental purpose is to uncover any ”hidden structure” that might be residing in a complex data set. PERMAP will run on Windows operating systems up to and including Windows 10. PERMAP takes object-to-object proximity values (also called similarities, dissimilarities, correlations, distances, interactions, psychological distances, dependencies, confusabilities, preferences, joint or conditional probabilities, etc.), or up to 30 object attribute values which can be used to calculate one of the forgoing types of proximities, and uses multidimensional scaling (MDS) to make a map that shows the relationships between the objects. Succinctly, PERMAP makes classical metric and nonmetric MDS analyses in one, two, three, … or eight dimensions, for one-mode two-way or two-mode two-way data, with up to 1000 objects and with missing values allowed. Ignoring jargon, PERMAP makes all the common types of MDS analyses. In addition, it can make several new types of MDS analyses involving error bounds or boundary conditions, and it can show the affect of degrading the proximity (similarity) information. PERMAP’s main claim-to-fame is that it lets you drag-and-drop objects in and out of the active set while the map is evolving and being displayed. It also allows complete on-line control of the badness function, distance metric, attributes-to-proximities formula, attribute set composition, mapping weights, and metric or nonmetric MDS, again, while the solution is running and the developing map is being displayed. The solution can be mirrored, rotated, translated, or zoomed. The bottom line is that PERMAP gives you more real-time control over your solution than any other MDS program. It lets you get a ”feel” for the solution and it lets you see, immediately, the changes that occur if you change any of your assumptions. PERMAP has been specifically designed to expose problems associated with local minima. If you have worked with MDS but have not discovered the high probability of the occurrence of results that are controlled by local minima then you need to experiment with PERMAP. This problem is well documented in the literature but too often is ignored by new users. The problem is not solved by using rationalized starting points. You have to experiment with real-time analyses, using real data, to really understand it. See the PERMAP operation manual for more information on this important point.
References in zbMATH (referenced in 1 article )
Showing result 1 of 1.
- Borg, Ingwer; Groenen, Patrick J. F.: Modern multidimensional scaling. Theory and applications. (2005)