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Visual Analytics Course


This section criticize bad or not so bad maps or interactive visualizations.

It is often worth looking and learn from bad design, as the Cartastrophe website suggests.

Death Penalty and Chernoff Faces

The designer of this one definitely should have to pay for its bad design. I got this one from the Cartastrophe website. Typing in “Death Penalty Chernoff Face” in your favorite search engine will easily lead you to the map.

The interest aspect of the map is that is wonderfully illustrate the point we are stressing here. That the communication channel can be disrupted at three different levels: operational (perception), articulatory and/or semantic. Each of these level here is undermined by this example.

Perception. The choice of colors definitely is not optimal. The main reason is because of poor contrast between colors, but also poor luminance contrast as well. Looking at their RGB values, the three colors used for the map regions are (close to):

  • (Purple) 134.45.134
  • (Maroon) 134.45.45
  • (Green) 45.134.45
RGB coding HSL coding
Purple 134.45.134 Hue 300, Saturation 49.7, Lightness 35.1
Maroon 134.45.45 Hue 0, Saturation 49.7, Lightness 35.1
Green 45.134.45 Hue 120, Saturation 49.7, Lightness 35.1

The poor contrast we observe may thus result from the fact that, taken pairwise, the RGB values of colors coincide on one of the components.

Back to the Perception section

/net/html/perso/melancon/Visual_Analytics_Course/data/attic/bad_map_examples.1380729684.txt.gz · Last modified: 2013/10/02 18:01 by melancon