This blog will focus on some lessons I learned from Stephen Few, namely from his book called 'Information Dashboard Design'. In the following story you will see 2 story points.
- How it shouldn't look
- How it should look
I have hidden 10 mistakes (10 things I find important, there is much more to learn from his book ofcourse!) in story point 1, try to find all of them before taking a look at story point 2.
Beneath the Story there will be a clarification for all 10 mistakes.
Have fun! (click on the image to check out the Tableau Public)
Here are the 10 hidden mistakes:
- Avoid scrolling in a dashboards
Always try to avoid having scrollbars in your dashboard. Your audience wants the most important information provided to them at a glance in a visual way on 1 single screen. There you have it, the definition of a dashboard!
- Give a meaning/context to your numbers
When you show numbers with a certain meaning (weight, value) on your dashboard always make this visibly clear. Take a look at the Shipping costs per order priority view. Both the axis as the tooltip mention the correct currency. This makes the viz more comprehensive and meaningful.
- Don't overkill your numbers
Think about the amount of decimal places your numbers should show. Besides scientific results, is it ever really useful to show more than 2? More than 2 only confuses and increases the difficulty to read the numbers. It increases the comprehension time, so it goes against one of the definitions of a good dashboard. Get information at a glance.
- Use the correct visual way of showing your data
There is a reason that Tableau suggests a certain visual representation. Try sticking to the best practices. For example in our story. I showed all months with their amount of customers. The best way to show data over a certain period of time is a line chart, let's say 9 out of 10 times.
- I want some variation?
No, just no. Having 5 bar charts on your dashboard is perfectly fine when this is the best way to show that data. The best example of some variation is the pie chart, it's a bad visualization but loved by many people.
- Mind your colors
Using colors in the correct way is a gift. Everyone can learn it, but few people 'feel' it. Always think about the following. Bright colors are used for highlighting and want to draw our attention, pale colors are enjoyable to read and more soothing. This sounds like pure logic? You would be surprised how many people forget this simple rule.
- Reduce the amount of pixels
This is the most important one for me. This literally means, ditch everything that has no use. Some examples: borders, grid lines (if they are useless), bold fonts for your titles, unused field labels, .. These things only distract when they don't have purpose. It takes time to read them which brings us back to the principle of getting information at a glance
- Mind the Z-pattern
It's proven that people tend to read a dashboard in a z-pattern. This means that they start at the top left. When you show an enormous logo they don't really start well on their 'dashboard journey'. Mind the size of your banner and title!
- White space
You feel unsure that your dashboard is readable enough? Doubting to add some borders to make it clearer? Don't! Just add some white space. Perfect solution.
- Color as background
To make it short, white is always the best background color. If you really want to use something different, use something that comes very close to white.
After removing these 10 mistakes, we get to the following result: