Colors of statuses in charts

Question

I am creating a dashboard for a system where I will use various charts to display data to the user (as of now I have pie charts and line charts).

The pie charts will display items with statuses for different queues; queued items, rescheduled items and expired items. Something like this:

In my color scheme I have some status colors to chose from; green, yellow, orange and red. In addition to these there are some other colors to play around with but I am not sure if I should go outside the status color scheme, I guess I will have to if the status color scheme is not enough.

The expired items is important to the user because he will have to do some sort of action to remove them. The rescheduled items will be run again within due time, without a manual action. The queued items is of course waiting to run, but the problem is that this number is "good" if the queue size is normal, but if the queue size is big, the user will have to do an action, or at least investigate the reason for the big queue size. This problem make me doubt if the green color (which other wise would be a good choice) is the right color for this purpose.

What would you say is an intuitive color of the different statuses?

Answer 1

Agreed about threshold color coding, as that's the point of using color in these status type of visualizations.

Consider ditching green and using neutral when there's no action.

Then, for the ones where the user needs to take action on warnings or something bad, use yellow, orange, red to go from bad to worst repectively. This may vary internationally, but is a general rule of thumb in the US.

A couple of resources you might find interesting to help more with your specific problem.

• http://stephanieevergreen.com/508-compliance-data-visualization/

• http://stephanieevergreen.com/dashboard-icons-in-excel/

• http://blog.invisionapp.com/finding-the-right-color-palettes-for-data-visualizations/

• https://www.geckoboard.com/blog/4-essential-steps-to-designing-a-dashboard-that-inspires-action/#.V24UQXopDqA

Answer 2

My suggestions:

• Color is a powerful tool, but you can add some labels. Don’t rely on color alone to deliver the informations;
• Choose colors that varies also in brightness. You can use soft colors to display most information and bright/dark colors to highlight information that requires more attention;
• To guarantee that most people who are colorblind can distinguish the colors, avoid using a combination of red and green;
• Read also Charts: Unlimited data, limited colors https://www.quora.com/What-are-the-best-UX-practices-for-charts-and-graphs-report-visualization

Answer 3

With pie charts, if you have a 500 item queue and 1 item is 'expired' then it simply won't show on the chart - it's just too small.

I think we suggested that you use stacked bar charts instead of pies: Data visualization for queued items. The height of the stack can show the length of the queue without crushing the 'expired' items.

Answer 4

If you're using a charting library with your data, you could possibly set up a color rule on the queue series. So if it goes over a certain threshold, it could change color from green to yellow, or another "warning" type color.

Here's an example where the bars change color depending on their value: https://www.zingchart.com/docs/json-attributes-syntax/loader/rules-abstract/?q=rules%20(abstract)#zcdemo