Bar Graphs W/ Intuitive Display of Variation (an Experiment)

by BoilingLeadBath in Workshop > Science

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Bar Graphs W/ Intuitive Display of Variation (an Experiment)

CDFBarGraphFinal.png
CDFBGMaleStature.png

I've been disappointed for a while now with the options for displaying population variation or uncertainty in graphs.

(For the files used to create the graphs, see here and here.)

Motivation:
As far as I can tell, there are three options for plotting :

  1. Standard bar chart + error bars (typically at +- 2*SD, ie. α = 0.05; For example)
  2. Co-graphed CDFs of the populations or samples (For example)
  3. Co-graphed histograms (or PDFs) of the populations (For Example)

My complaint is that:

  1. Requires that the reader be familiar with the concept of population variation and/or uncertainty; it does not provide intuitive support for the idea.
  2. Is a somewhat unusual type of graph, so the unsophisticated may not know how to read it. Plus, it gets messy when a large number of data series are graphed.
  3. Is just plain weird to read if there's substantial differences between the variation of the datasets.

To that end, this instructable is an experiment in intuitive, layman-friendly presentation of population variation within a bar chart by, essentially, topping each bar with a CDF.

Let me know what you think!
Also let me know if you know of any work similar to this, or if you have any ideas on the topic.

Creating Said Charts

CDFBarGraph.png
CDFBarGraph2.png

Since this is an early experiment, my process is pretty rough (and time consuming), but here goes:

  1. Use Excel's X-Y plot to draw some bars. (files here and here; all user-modified values on sheet 1, calculations on sheet 2.)
  2. Use your photo-editing tool of choice to fill in the bars. I use paint; takes about 1-2 minutes per bar, depending on geometric complexity.
  3. Add legends, axis labels, etc.