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Goodness/Badness of Visualization Depends on Interpretation

In particular, it’s fragile to the interpretation of the following:

  1. Who is the target audience?
  2. What is purpose? E.g. if it’s explanation, what’s the story?

Perspective 1: Without a sense of humor, this is a terrible visualization

Basics of current visualization

  • Target Audience: People interested in the height of the WTC over time
  • Exploration or explanation: Explanation
  • Purpose: Inform people of the sudden drop in height after 2001
  • Story: Height is stable at ~1750ft until 2001, after which it is 0
  • Idiom: 3D bar chart
  • Data scale: Ratio

Issues

Wrong abstraction

  • Story is about presence of height, not particular value of height
  • Suggestion: re-encode the magnitude channel of the bar chart into an identity channel (has height vs doesn’t have height)

Wrong data scale

  • Should be ordinal (only 2 distinct values ordered by magnitude), or even nominal (a binary encoding to highlight)

Bad idiom choice

  • 3rd spatial dimension encodes no additional information
  • Bar chart values are needlessly imprecise
  • A lot of ink to show very little information (not the same as a low data-to-ink ratio. This is more like information-to-ink ratio and is an encoding problem)

Insufficient data to establish trend

  • Suggestion: add 20 years of height data before and after

Data is inaccurate

  • Height of WTC is 13

Suggested Viz Mockup

Perspective 2: With a sense of humor, this is very good

Basics of current visualization

  • Target Audience: People who enjoy dark humor
  • Exploration or explanation: Explanation
  • Purpose: Make audience laugh
  • Story: The planes that destroyed the twin towers changed their height to 0ft
  • Idiom: 3D bar chart
  • Data scale: Ratio

Nice touches

  1. Great idiom choice: 3D barchart allowed a symbolic representation of the two towers (using the bar volumes of the first two datapoints)
    • Note: Data scale needs to be ratio for this joke to work, so that the bar chart symbol of the towers can be constructed out of the magnitude channel
  2. The indirect encoding of the data of the planes crashing makes the joke funnier, as the audience comes to the realization of what is truly represented on their own
    • Would be less funny if the audience hadn’t gone through the emotional journey of confusion (Why did the height suddenly drop? Oh 9/11 LOL) and were just told the takeaway directly (no 9/11 until 2001)