Second URL: http://tinyurl.com/2ox9wf

"The code for displaying and interacting with radial, space filling trees in prefuse is open source, and is available for download. The code is distributed as a zip file and can be imported into Eclipse. It is dependent on the prefuse information visualization toolkit and, unfortunately, is minimally documented at this time:" http://www.cs.utoronto.ca/~ccollins/research/docuburst/rsfTree.zip

DocuBurst is the first visualization of document content which takes advantage of the human-created structure in lexical databases. The authors used an accepted design paradigm to generate visualizations which improve the usability and utility of WordNet as the backbone for document content visualization. A radial, space-filling layout of hyponymy (IS-A relation) is presented with interactive techniques of zoom, filter, and details-on-demand for the task of document visualization. The techniques can be generalized to multiple documents.
To use DocuBurst, a user loads a document of interest into the visualization, and chooses a WordNet node at which to root the visualization. Below, we see that "idea" was chosen to root the visualization, and the occurrences of concepts that fall under "idea" appear in the visualization. The gold coloured nodes indicate search results for nodes matching 'pl' at the beginning.
The visualization can be used to drill down into the loaded document. A paragraph browser, with a fish-eye lens, at the right of the DocuBurst display shows which paragraphs in the document from beginning to end (top to bottom) contain the selected node. By clicking any of the paragraph numbers the full text of that paragraph is shown in the details window, with occurrences of the selected node highlighted in the text.

"A new data visualization method for representing document content by a radial space filling layout technique. "docuburst" aims to provide a more intuitive abstraction than those developed through statistical techniques.the root node is shown as a circle. all other nodes are assigned to a sector of an annulus with angular width which is part of the parent node’s width, depending on the amount of word occurrences. Highly colored nodes have many occurrences, while almost transparent nodes have few occurrences."

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