Regular readers of this newsletter will know that I believe that focusing on the right data is more important than focusing on big data. And a similar comparison can be made for data visualisation where an easy to understand visualisation that tells a story is much more useful to a decision maker than a dump of data that is turned into a graph.
One of the things we look for when hiring new data analysts is their ability to interpret data to tell a story or draw some conclusions from it. It is often much easier to simply generate charts from a data set and present it back but the real skill comes from displaying your findings in a way that quickly gets a message across. Here’s a simple example of how data can be visualised in slightly different ways to create a more meaningful and concise story.
Consider this chart of the decline in reading among Americans between 1978 and 2014.
On i’s own the data makes sense but this graph buries the story and is difficult to interpret, you still need to study the graphs to understand exactly what is happening.
1. There’s too much data. The 1990 Gallup poll doesn’t really add anything.
2. It goes from new data to old, even though every other table in the world gets newer as you move right.
3. It is too complete, giving us not only the useless “no answer” category but two stats in the middle that hardly changed.
We can quickly clean it up and get this:
But it still doesn’t work hard enough to say what we want to say. Footnotes belong in the footnotes, along with links to the underlying data in case we want to see for ourselves. But here is the truth of this data, a story well told:
This is a very simplistic example of how the same data can be cleaned up and used to tell a more compelling story in a simplistic and easy to absorb manner. Often data visualisation can be seen as an afterthought to the actual data crunching, something that is created automatically, but by spending a little more time making sure your visualisation is easy to understand and shows just the information needed, you can make quicker and more informed business decisions.