In general any visual representation of data is the most efficient form of putting your point across. A picture is worth a thousand words. It is true, not only in the art world but also in the business & academic worlds. Graphs, all sorts of them, stem, box, scatter, histogram, bar, pie & 3D are all used as windows for looking deep into the otherwise shallow looking & less informative pool of data points. Graphs have the power to harness the might of the human neural network to discover new dimensions which otherwise would always be inherent. This is exactly why one should be really careful while choosing the type of graph in order to paint the ‘best picture’
Many online & offline magazines make use of Pictograms and 3D plots in order to present data to the public. Pictograms and 3D plots though may look very appealing can usually mislead us while interpreting the data. A couple of examples of such cases are shown below.
The above example is a pictogram that aims to show the distribution of advertising budgets across TIME, Newsweek & US News. What is clear is that TIME attracts the largest amount of advertising spending followed by Newsweek & then US News. What is interesting to note is that having a look at the figures quoted in the picture tells you that the ratio of TIME’s to Newsweek’s share is around 1.6 and that of TIME/US News is around 2.9. This means that TIME should be only about 1.6 times larger than Newsweek and only 2.9 times larger that US News. But according to the pictogram TIME looks definitely more than the above ratios. What is this visual discrepancy?
Well what actually happened is that the picture in the pictogram was magnified and used for the three data points. While magnifying the picture both the height and width have been increased proportionally to avoid distortion. This means that the actual increase in size between the TIME’s figure and Newsweek’s figure is actually 2.56 (1.6*1.6, accounting for both height & width). Similarly the increase in size between Time’s figure and US News figure is 8.4 instead of 2.9.
So, our eyes, which capture the area of the pens rather than only the height, are misled to think that TIME’s share of budgets is way ahead of its competitors while it actually is not
The following is another example of an unnecessary use of 3D plot to present the data.
The aim of this graph is to showcase the drastic increase in the number of Starbucks outlets around the world. If you look at the graph carefully between 1999 & 2003 there is an increase from about 2000 stores to a little more than 6000. This is effectively an increase of about 200%. But the from the graph below it appears that the increase is much bigger than what the actual numbers suggest.
Using a 3D graphs brings in with it another problem, the third dimension. So when a 3D picture is magnified the height, width & breadth are all simultaneously increase to avoid distortion. This is the reason the picture looks much bigger than the 200% increase suggested by the numbers.
So essentially make use of the traditional 2D plots for the best and most accurate representation of your data.