Scatter plot enhancement: Target bands, medians, and quartiles

I take a lot of inspiration from really good charts. Some charts are meticulously hand-crafted to best express a specific data set. That's not really an option for mass-produced/dynamic dashboard charts like we'll use Domo for. But some designs are robust and useful enough to handle large, variable data sets. As an example of such a design, here's a chart I was pretty impressed by last year:














It might not strike others as so impressive at first, but note that it may be summarizing thousands of data points (or more.) With the lower/upper target lines, the quartile bands and the rolling median, it's easy to see at a glance how things are doing. This works at even a very small scale. This particular graph is based on 21 days of data on a 24 hour clock. So you get to see hourly trends for free. In this case, the chart is for blood glucose readings, but it could be for attendance/participation rates, defects in assembly, production measures, temperature readings in furnace, O2 levels in a burner, anything. I've seen a lot of time-trend data charts, but rarely one so economical and information-dense.


This design hits all of these marks at once:

  • Informative at a glance.
  • Effective at small or large scales.
  • Capable of handle large data sets.
  • Visually engaging
  • Encourages exploration, particularly in the second example shown below.

Here's a second version of the same chart that I like even better:















It's the same chart with the underlying data points plotted on top. The first chart is easier for spotting trends at a glance, but the second is more interesting for getting a visceral feel for the data set and it's ranges - something that a data table holds but can never do. Also, it ticks another box inviting exploration of the outliers. What are those rare dots? They just beg to be hovered over or clicked on.


From hunting around in the docs and the Dojo, I can see that Forecast Graphs already do part of this, and that quartile and summary lines do more. Still, I don't think it would be possible to reproduce these charts in Domo....and these charts are awesome.


I can also see that there is a lot of work being done on various charts, like Box Plots and Scatter Plots and am hoping that I'm submitting these examples at a good time in the development cycle.




P.S. Box Plot Love is a great request and beautifully explained. I figured the examples posted above are different enough to make a distinct post.

2 votes

· Last Updated

This discussion has been closed.