The use of graphical methods to convey complex statistical information dramatically to a broad audience is not new. http://www.datavis.ca/gallery/historical.php This data viz collection cites splashes of brilliance.
A picture is worth a thousand words – or a thousand Excel data points, and Michael Sandberg at DataViz blog says he “preaches to everyone (or anyone who will listen)” that he aims to “get our business partners or clients excited about their data.” DataViz blog here examines and gushes over the famous Charles Minard graphic of Napoleon and the Russian Campaign of 1812. While hundreds of essays laud Minard’s graph scrutinizing its multi-layered, brilliant story-telling – of a multi-layered, brilliant, poignant story – right down to the color palette (which itself is meaningful), Sandberg’s article helpfully lists aspects to remember when we set out to build a good graphic.
“What does the map show us?” A lot, is the answer: humanity writ large and very, frost-bitten, face-down in Bereniza, small. It’s data visualization fraught with the invisible from Minard’s personal politics to a “know your audience” marketing that recognizes, frankly, that people don’t like to have to go from page to page to make comparisons, so help them see the story.
1) Forces visual comparisons (the upper lighter band showing the large army going to Moscow vs. the narrow dark band showing the small army returning).
2) Shows causality (the temperature chart at the bottom).
3) Captures multivariate complexity (size of army, location, direction, temperature, and time).
4) Integrates text and graphic into a coherent whole.
5) Illustrate high quality content (complete and accurate data, presented to support Minard’s argument against war).
6) Place comparisons adjacent to each other, not sequentially (people forget if they have to go from page to page ).
7) Use the smallest effective differences (i.e., avoid bold colors, heavy lines, distracting labels and scales).