While visualization can be an effective tool to understand data, too many software vendors seem to view visualization as an opportunity to "bling your graph" according to Stephen Few author, teacher and consultant. Few has written a new book just published called "Now You See It: Simple Visualization Techniques for Quantitative Analysis". He spoke to the SDForum Business Intelligence SIG June meeting.
Few took us on a quick tour of visualization. We saw a short Onion News Network video that satirized graphics displays in news broadcasts, followed by examples of blinged graphs and dashboards that were both badly designed and misleading in their information display. Not all visualizations are bad. An example of good visualization is the work of Hans Rosling who is a regular speaker at the TED conference (his presentations are well worth watching, and then you can go to Gapminder.org and play with the data just as he does). Another example of visualization used effectively to tell a story is in the Al Gore documentary "An Inconvenient Truth".
Next came a discussion of visual perception, leading up to the idea that we can only keep a few items in our short term memory at one time, however these items can be complex pieces of visual information. Given that data analysis is about comparing data, visual encoding allow us to see and compare more complex patterns than, for example, tabular data.
Any data display can only show us a small part of the picture. An analyst builds understanding of their data set by building up complex visualizations of the data, piece at a time. We saw some examples of these visualizations. Software should support the data analyst as they build up their visualizations without getting in the way. Few told us that the best software is rooted in academic research. He recommend several packages including Tableau and Spotfire, both of whom have presented to the Business Intelligence SIG in the past.