Data Viz Done Right

June 9, 2014

Makeover Monday: Label bar charts for easier comprehension

5 comments
I'm in the market for Chromebooks for my twins and was reading quite an excellent overview by The Wirecutter. In the middle of the article is this chart comparing the performance of various Chromebooks:


This chart seems innocent enough, yet I found myself having to constantly reference the legend because they didn't bother including the labels directly on the chart. A more understandable alternative might look like this:


In this chart I have:
  1. Added labels for the bars
  2. Removed the legend and the different colors for each Chromebook
  3. Made the bar horizontal bars so that the labels are easier to read. I also find it easier to compare the length of the bars on horizontal bar charts, but that's a personal preference.
  4. Added a metric to show how much slower the other Chromebooks are compared to Wirecutter's recommendation (Dell Chromebook) and colored the bars by the % difference. This helps provide more context to the speed comparisons and I don't have to do the math in my head.

5 comments :

  1. Love the Monday Makeovers! Question about your take on labels at the end of bars. In this case, each label has the same number of characters so this point may be moot. But I've read arguments in the past that the labels can lead one to misinterpret the length of the bar when viewing at a glance. Therefore, when possible, labels on the bars would be preferred.
    A little picky but would love your take on that.

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    Replies
    1. The labels should ALWAYS have the same precision. Putting them inside the end of the bar works as well. I'm indifferent to it.

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  2. Good tip! I've always been a proponent and fan of using horizontal bars instead of vertical for this main reason of having each bar individually labeled instead of relying on a multi-color legend.

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  3. Excellent makeover. The only thing I can imagine that would add more clarity is to indicate that smaller bars are better. It wasn't immediately obvious to me from the chart that the Dell was the best until I read below that "Dell is the fastest". Curious what your preferred method would be. Some options...

    * Area annotation with "Fastest" at the top and "Slowest" at the bottom
    * Area annotation with just "Fastest" at the top
    * Visually highlighting Dell with a small "Fastest" icon (or Rabbit vs. Tortoise, etc)
    * Putting back the legend "Lower numbers indicate better performance" (kind of Blah)

    ReplyDelete
    Replies
    1. Good feedback Steve. Including that in the title would probably be best. I imply that by the % difference in speed, but I can see where that could be misinterpreted too. Thanks for the feedback!

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