We (datavis folks) like to believe that one of the key advantages of charts over tables is that charts are much better at providing context, displaying patterns and so on, while a tables “merely” gives you the exact value.
Fortunately, life is not that simple. Many people dislike charts and a good table with the latest data is more than enough to get the insights they need. This kind of puzzles us. Haven’t they seen the light yet?
Is context overrated?
Let me put it this way: external visual context may be overrated.
Suppose you’re a programmer. You want to solve a very specific problem, like making a routine run faster. You search your favorite tips & tricks site and find what you were looking for. End of story. Your knowledge and experience provide all the context you need. Let’s call it internally supplied context.
If you are a beginner things are a bit different. You probably don’t even know that your routine can run faster. If you do, you don’t exactly know what to look for. And if you do, you don’t know how that new piece of code works and you need help. You need explicit externally supplied context.
Journalists and graphic designers love external context (hence they love charts) because they are not subject-matter experts. They work with other people’s data. If I say “an unemployment rate of 12.1%” a subject-matter expert can easily provide internal context, while the journalist (and her audience) need a more explicit external context.
Are patterns overrated?
I’d like to know more about table-based decision-making process, but I suspect that people are less aware of data patterns and more interested in some kind of fluctuation bands, and they compare data points against them. This is an interesting alternative data reduction technique.
The dangers of a consolidated knowledge
Internally supplied context and fluctuation bands are two by-products of a mature and consolidated knowledge. They can be very effective in decision-making and help seeing beyond short-term trends. On the other hand, in a rapidly changing environment they can (dis)miss relevant but unexpected changes.
So, what do we do?
We may not like it, but we must accept the fact that some people are less visual that others and that they can get the information they need from a table or a written report. They already know what they need to know and they can provide the necessary context to deal with a few data points. A chart is useless and redundant.
How can we convince them that a chart is a good thing? Well, try this:
- Don’t tell them quantitatively what they already know qualitatively.
- Show them more complex relationships.
- Try to find unexpected patterns.
- Try to find their pain points and solve them (all processes can be improved).
So, what do you think? How can you convince a table person to become a chart person?