CPSC 533C Assignment 1

Allan Rempel

Due September 14, 2005

The following two images depict a "good" and a "bad" use of information visualization. In this case, both uses come from the same article, on Hurricane Katrina, in Science magazine.

What constitutes "good" and "bad" is of course subject to considerable debate. For the purposes of this assignment, I will deem that a "good" visualization is one that is immediately accessible to me, the viewer, and conveys its information to me without the need for me to expend significant time attempting to understand the visualization. In addition, the visualization must present a reasonable amount of data such that it is worth it to me as the viewer to actually look at it.

Who am I? I am a reasonably well informed and educated person. I have studied weather in the context of a flight school, in the process of earning a pilot's license, but I have no particular expertise in hurricanes beyond that, making me an informed lay audience. I am probably very typical of readers of Science.

The previous visualization is good because it is immediately obvious what it is. The data being displayed is displayed in an appropriate and instantly recognizable context. The content of the data itself, including the size of the hurricane and the temperature of the surrounding water, are very quickly made apparent to the viewer.

The above visualization is not nearly as good as the previous one because it takes a fair bit more processing in order to determine what is being presented. An explanation is required to realize that the geographic area depicted is New Orleans. It is also not clear what the depicted time line is, or even what the chronological order of the images is; the viewer is left to assume that the top one is first and the bottom one last. The legend information is also not as clear as in the first image. This image arguably presents more information than the first one does through its use of current velocity arrows, but that additional detail does not really pay off more than the detail depicted in the first image.