Panopticon recently gave me a preview of a new edition of their treemapping software, which was officially released today (see the press release). A learning edition of Panopticon Explorer .NET can be downloaded for free, which provides a useful means to get acquainted with treemaps for visualizing hierarchically arranged quantitative information. You have probably seen examples of this approach, such as SmartMoney.com’s Map of the Market. Treemaps were originally invented by Dr. Ben Shneiderman of the University of Maryland as a way to maximize screen real estate for simulatenously displaying two related sets of hierarchically or categorically arranged quantitative variables: one encoded as the size of rectangles (for example, a stock’s volume) and the other as the rectangle’s color (for example, a stock’s price or change in price since yesterday). When used effectively, treemaps can provide a quick overview of the data in a way that makes exceptional conditions pop out, such as big changes in stock prices. If this topic interests you, I will feature an article about treemaps by Ben Shneiderman in the April data visualization edition of he Business Intelligence Newsletter from the Business Intelligence Network.

Panopticon has incorporated some nice features into their software for viewing and interacting with the data, so you might want to take a look.