A1-WittonChou
From CS294-10 Visualization Fa08
Good Visualization
Source: "The Mind-Body Interaction in Disease" p 14, Scientific American: Mysteries of the Mind. 1997
Explanation: This visualization clearly depicts how the cerebral blood vessal can carry immune cells that release chemical messengers that trigger responses if they pass through the blood-brain barrier. The important elements are large and in the center of the picture. Important elements such as a leaky junction in the blood-brain barrier are labeled. Arrows are used to depict what happens when IL-1 binds to receptors that line the cerebral blood vessels.
Deconstruction: This is a three dimensional representation of a cross section of a cerebral blood vessal as it pertains to the chemical interaction between the brain and the body. Pertinent parts are clearly labeled: hue and saturation differentiate between the blood vessel, blood contents, and the brain. Arrows depict progression of the chemicals as they bind to receptors and leave the bloodstream. We can tell that IL-1 comes from the monocytes and bind to receptors on the blood vessel lining or break through gaps in the lining.
Bad Visualization
Source: "Brave New World of Wiretapping" pp 58-59, Scientific American, September 2008.
Explanation: At first, I thought this would be a good visualization, but as I tried to understand it for myself, I ran into several problems and it took me a long time to get a vague idea of what is being shown. Upon inspection, we see that the key can be a little misleading. Wireless communication is represented by a dotted/dashed line which can be protected (black) or unprotected (red), not just protected (black) as the key may suggest. When we look at the map itself, we see that the lines can change color (as communication lines/signals leave the country). There are a lot of ambiguities that arise when trying to decipher this map, which make this a bad visualization.
Deconstruction: There are six variables on this visualization: a U.S. person (blue circle), Non-U.S. person (yellow circle), protected wired communication (solid black line), unprotected wired communication (solid red line), unprotected wireless communication, (dotted red line) and protected wireless communication (dotted black line). However, the key is ambiguous: wired communication and wireless communication are encoded as gray lines differentiated as dotted being wireless and solid being wired; line protetion is differentiated as red and black solid lines. Although once one understands the visualization it is useful, the key can be very misleading.
Redesign:
Several subtle fixes were made here. The original visualization had good labels describing the meaning behind some of the lines drawn for clarity. However the main issue with the original visualization was with the misleading key. The redesign fixes the issue with confusing the gray lines and encodes the data with a more specific key, labeling the for types of communications lines with exactly what they mean. I also realized that some communications lines have origins outside the U.S. or originate inside the U.S. but are routed internationally before they reach the destination. These lines that transit internationally are differentiated with X's on the lines.
