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Is there a particular name for bar plots, in which bars are rectangular, with unequal bases?

That is:

  • width represents size (e.g. population),
  • height represents intensive variable (e.g. CO$_2$ emission per capita),
  • area represents extensive variable (e.g. total CO$_2$ emission).

Example (from David JC MacKay, "Sustainable Energy - without the hot air", page 14):

CO2 emission rate by country

In the same vein: this and that. Another one: "Real GDP Per Capita and Shares of Global Population" (found here):

enter image description here

I find these plots immensely useful, as they show both the local effect (is a country particularly rich, polluting, militaristic...) and the global share (of economy/pollution/military power).

I have even made one: Research publications per capita? - Academia.SE. I care for its name both to search for examples, plotting libraries/functions etc, and to propagate this way of presenting data.

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Piotr Migdal
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    All bars are rectangular (quadrilateral with four right angles)! What's a little unusual here are the varying (unequal) bar widths. Plotting cumulative shares like this is perhaps more commonly done using a Lorenz curve, which in turn is a kind of P-P (probability-probability) plot. You have here discrete versions with several bars identified. I don't know that this has, or really needs, a distinctive name. Your second graph is closer to a Lorenz curve; the first has extra structure given by grouping. – Nick Cox Jun 29 '15 at 13:17
  • @NickCox I missed "uneven base" (fixed). Thanks for brining [Lorenz curve](https://en.wikipedia.org/wiki/Lorenz_curve) (I know it, but I was not thinking about it as bar plots from this question can, but don't have to be, ordered). – Piotr Migdal Jun 29 '15 at 13:21
  • Small corrections: In English we would not say "uneven"; that's for surfaces not quite flat or smooth. It's Lorenz: Lorentz was a different person altogether. Key point: You are correct: bar charts with touching unequal width bars do not have to be ordered. But they are not of much use or interest without an ordering of some kind. – Nick Cox Jun 29 '15 at 13:24
  • @NickCox Lorenz - fixed (I can never remember, same Schwar(t)z). Well, there are other orderings, which make sense (e.g. as in the example 1); or there may be no ordering if there are only a few values. Is "variable bases" OK? – Piotr Migdal Jun 29 '15 at 13:31
  • My suggestion on wording remains varying or unequal bar widths. As the word "varying" or "variable" is likely to occur often in any report, as a matter of style "unequal" might be preferred. (Schwartz for Schwarz is indeed a very common mistake, whether it is the Cauchy-Schwarz inequality or Schwarz's BIC.) – Nick Cox Jun 29 '15 at 13:36
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    Kaiser Fung points out the shortcomings of that GDP chart in his [junkcharts blog](http://junkcharts.typepad.com/junk_charts/2014/08/world-bank-fails-to-lead-the-way-in-dataviz.html) and a [follow-up post](http://junkcharts.typepad.com/junk_charts/2014/08/mind-your-qs.html). – xan Jun 30 '15 at 12:55
  • @xan Each data visualization method has its strong and weak parts. True - comparing at exact areas is difficult. Yet, for the alternative it's hard to sum things (e.g. in the cascade plot it is simple to estimate Europe vs Africa; for scatter plots - it isn't). – Piotr Migdal Jul 01 '15 at 16:51

1 Answers1

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Apparently they are called cascade charts, see:

As a bonus, ggplot2: Variable Width Column Chart.

However, sometimes cascade chart is used as a synonymous of waterfall chart (which is a different thing from the discussed above), see e.g.:

In any case, judging for length I needed to get this answer, this name may be not that popular even among people creating similar bar plots (and perhaps a descriptive way may be better).

As was pointed out by @NickCox, if bars are sorted by their height, it is a discrete variant of the Lorenz curve.

Piotr Migdal
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    I found three quite different meanings for waterfall plot or chart in a search a while back. Picturesque name, inconstant interpretation. – Nick Cox Jun 29 '15 at 18:42