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Depicting imbalance, straying from the standard chart

My friend Tonny M. sent me a tip to two pretty nice charts depicting the state of U.S. healthcare spending (link).

The first shows U.S. as an outlier:


This chart is a replica of the Lane Kenworthy chart, with some added details, that I have praised here before. This chart remains one of the most impactful charts I have seen. The added time-series details allow us to see a divergence from about 1980.


The second chart shows the inequity of healthcare spending among Americans. The top 10% spenders consume about 6.5 times as much as the average while the bottom 16% do not spend anything at all.


This chart form is standard for depicting imbalance in scientific publications. But the general public finds this chart difficult to interpret, mostly because both axes operate on a cumulative scale. Further, encoding inequity in the bend of the curve is not particularly intuitive.

So I tried out some other possibilities. Both alternatives are based on incremental, not cumulative, metrics. I take the spend of the individual ten groups (deciles) and work with those dollars. Also, I provide a reference point, which is the level of spend of each decile if the spend were to be distributed evenly among all ten groups.

The first alternative depicts the "excess" or "deficient" spend as column segments. Redo_healthcarespend1

The second alternative shows the level of excess or deficient spending as slopes of lines. I am aiming for a bit more drama here.


Now, the interpretation of this chart is not simple. Since illness is not evenly spread out within the population, this distribution might just be the normal state of affairs. Nevertheless, this pattern can also result from the top spenders purchasing very expensive experimental treatments with little chance of success, for example.


Graphical inequity ruins the chart

This Economist chart has a great concept but I find it difficult to find the story: (link)


I am a fan of color-coding the text as they have done here so that part is good.

The journalist has this neat idea of comparing those who are apathetic ("don't care about whether Britain is in or out") and those who are passionate ("strongly prefer" that Britain is either in or out).

The chosen format suffers because of graphical inequity: the countries are sorted by decreasing apathy, which means it is challenging to figure out the degree of passion.

This chosen order is unrelated to the question at hand. One possible way of interpreting the chart is to compare individual countries against the European average. The journalist also recognizes this, and highlighted the Euro average.

The problem is that there are two different averages and no good way to decide whether a particular country is above or below average.

Here is my version of the chart:


The biggest change is to create the new metric: how many people say they really care about Brexit/Bremain for every person who say they don't care. In Britain, over four people really care for each one who doesn't while in Slovenia, you can only find fewer than half a person who really cares for each one who doesn't.