The persistence of underdogs

March 24, 2011

NCAA basketball bracket

Infographic by Leonardo Aranda

In the process of discussing the NCAA baskbetball tournament last week, we stumbled on a diagram by Leonardo Aranda that was featured on the Good blog before the 2010 tournament. As with many infographics, the first thing we noticed was that it is aesthetically stunning. However, knowing that infographics are often accused of being just pretty pictures, we thought we would take a closer look at what the diagram accomplishes. How would someone actually use this diagram to learn something?

Our first thought was that this might be useful for choosing one's bracket, but after further reflection we realized that there are a few things about this diagram that make it difficult to use as a bracket selection tool. First and foremost, the top seed is not always assigned to the same region (as discussed on Aranda's orginal post). As a result, showing the full bracket can lead one to incorrectly conclude that the "blue" (lower-left) and "pink" (lower-right) regions are considerably stronger than the "red" (upper-left) and "green" (upper-right) regions. This fact begs for the analysis to be aggregated across regions. Secondly, it is difficult to tell the relative fraction of 14-seeds, for example, that appear in successive rounds of the tournament. Finally, it is not obvious how long upsets persist in the tournament. What does history tell you about picking a 6-seed to the Final Four?

Rather than using this diagram as a “bracket selection tool,” I think this diagram more effectively accomplishes a different goal — educating us on the chance of a particular seed of winning the tourney (or making it to a particular round). With a quick glance at this diagram, one can understand how often teams are upset, and how often those upsets persists to the later rounds. That way, we know that, while picking a three-seed to win the tourney might not be that crazy, picking a sixteen-seed to go the final four is downright stupid.

That being said, we would like to explore how this visualization might be improved to accomplish those goals more effectively, while still retainiing the strengths of the diagram:

  • It evokes the March Madness tournament by mimicking the bracket's iconic regional layout.
  • It showcases the frequency with which various seeds from different regions win the tournament
  • It effectively uses color to showcase frequency of champions from different regions.
  • It illustrates the frequency with which different seeds appear during each round of the tournament.

As always, additional comments are welcome and encouraged! Stay tuned for our attempt at creating a similar diagram...

contributors to this post

headshot of Dean Malmgren
headshot of Mike Stringer