Statistical Graphics and more

This time it is easy for me, as I just need to point to the interesting discussion at Junk Charts.

The original graphics is from the NYT:

The “improved” plot looks like this:

The advantages of the box-plot view (from Junkcharts)

• The European market is much more fragmented than the U.S. market.
• The Big 2 (GM, Ford) has had mixed fortunes over this period (as indicated by the large variance)
• The Big 2 are competitive in Europe although they are definitely not dominant there
• Several key players in Europe (Peugeot, Renault, Fiat, BMW) have negligible shares in the U.S

The discussion was quite lengthy, but had the two major points:

• Boxplots are too hard to read for NYT readers
• The boxplots ignore the temporal information and thus are not really suitable for this data

One important point was not mentioned explicitly, which is

• Sorting is a very powerful and important option in graphics

There is truth to all the issues raised here, and the bottom line is probably that there might be not a single graphical view on the data which covers all aspects of the data. Furthermore, the NYT graphics is by far the most eye-pleasing version of all suggestions.

In this spirit I want to throw in two more versions which show the data:
Two variations of Mosaic Plots (will be explained in the next ‘statistical graphics 101’) in the multiple barchart view. European cars are highlighted:

(Year x Brand x Continent)

(Continent x Brand x Year)