Last week I attended a lecture by Andries van Dam (Brown University's Vice President for Research) entitled Immersive Virtual Reality in Scientific Visualization. He highlighted how their Cave project was allowing geologists to explore Mars (and train astronauts for their eventual missions on the planet). He closed the presentation with a couple of tablet PC applications, one for chemistry that allows you to hand draw 3D models of molecules and the other, a math visualization program.

The math application (MathPad²) was actually a lot cooler. The premise of the software is that it's far easier to hand write complex mathematical formulas than it is to type them in (ever try to type in a calculus problem?). Not only does the software allow you to write down your problem, you can then draw pictures to simulate the mathematical formulas you wrote down. You can see an example of the difference between constant speed and velocity (along with damped harmonic oscillation) at their site.

These examples got me thinking about how we visualize our data. Take a blog for example. We generally tag (or otherwise categorize) the content we author. But what exactly does that mean? I believe this is where data visualization begins to play an important role.

When you go to a site with a tag cloud, you can quickly infer information about the content of that site. If, say, ColdFusion is denoted in a larger font in the cloud than ASP, you may conclude (even if at a subconscious level) that the site is geared more toward ColdFusion than ASP.

There's a small (some may argue that it's actually quite significant) flaw in this data visualization...you cannot see the interaction between the different tags, nor their relation to individual postings.

This is where things like topic maps and TouchGraphs can signficantly help to show the interaction and relationship between individual entries. There are already several applications of this type of technology out there (there's a list at the bottom of the post).

My experiment in RSS visualization uses Hypergraph and Ray Camden's Blog CFC. The Hypergraph project provides an Applet that performs the visualization interpretation from an XML document that gets generated at the time the page is called.

The logic is pretty rudimentary. Every category/tag in the blog is linked to a root node (the blog name). Then every entry is generated as a new node and connected to its category node(s). The result is a web of inter-connected links that visually show the connections between individual entries and their categories.

You can see the visualization here.

I think this particular implementations has a few drawbacks. For instance, there's no relation expressed between nodes other than a line. A better way to do this is to implement a similar item with a topic map that expressly denotes relationships between the categories. But I'll leave that until after Christmas.

Text Visualization Sites inxight thebrain thinkmap