Treemaps: Evidence of Unseen Patterns
Data visualization is something that interests me greatly, and as I read my book on designing with data, I thought it would be appropriate to analyze current data visualizations that live up to the challenge of complex data sets.
One such visualization goes by the name of Newsmap. It is meant to be a visualization of the google news aggregator and displays the subsequent data in the form of a treemap. It’s creators felt a need to rise to new user interface challenges that have arisen since our society is becoming increasingly soaked in data.
Treemaps display hierarchical (tree-structured) data as a set of nested rectangles. Each branch of the tree is given a rectangle, which is then tiled with smaller rectangles representing sub-branches. A leaf node’s rectangle has an area proportional to a specified dimension on the data. Often the leaf nodes are colored to show a separate dimension of the data. Essentially each of the leaf nodes or cells of the treemap are coloured differently in order to demonstrate a different subset of the same data.
When the color and size dimensions are correlated in some way with the tree structure, one can often easily see patterns that would be difficult to spot in other ways. A second advantage of treemaps is that, by construction, they make efficient use of space. However, this is also dependent on the dataset. You’ll find that the more data you decide to look at on the treemap the less space you have on you current monitor, in my case, my 13-inch macbook screen is not sufficient for more than one subset of data at a time.
The treemap that is being utilized by Newsmap show a lot of interesting news patterns. The size of the cells in Newsmap, the dimension of data that it is displaying, appear larger or smaller depending on the number of related articles that exist on a particular subject. These unseen patterns can give us a better understanding of what sells news papers, and what our society values in terms of news. This is a valid statement because the google news aggregator in an of itself is an application that gathers news from various sources without much human intervention, and in so doing essentially makes its gathering practices objective to a certain degree.
In any case, a treemap is an interesting and versatile method of data visualization for multiple dimensions of data which makes efficient use of space, and easily allow its viewer to see rough unseen patterns in data. Of course all this also depends on the type of data that we choose to analyze. Treemaps seem to be better suited for large data sets with multiple dimensions of measure. It analyzes data hierarchically, from broad to specific and as such is suited for large data sets.
All in all, they are interesting visualizations of data, particularly that of Newsmap.
Shneiderman, Ben; Plaisant, Catherine (June 25th, 2009). “Treemaps for space-constrained visualization of hierarchies”. Retrieved February 23, 2010.
Suda, Brian (August 10th, 2010). “A Practical Guide to Designing with Data”. Five Simple Steps: Stanwell, England.