In 1995, a testbed of 110,000 Internet homepages from the entertainment section of Yahoo! was gathered by an Internet Spider. An automatic indexing algorithm was applied to the homepages and a concept space (ET-Space) and multi-layered Kohonen SOM (ET-Map) were created.
A 2-D multi-layered SOM was generated from the entertainment collection. Text labels and colors are used to demarcate regions in the SOM, color has no specific meaning. SOMs will cluster similar categories near each other on the map. Clicking on a map region will take you down a layer in a multi-layered map, or show you the documents associated with that category if the number of documents is less than 200. [url]
This image is based on the ET-Map created by a team led by Hsinchun Chen. © National Science Foundation