How to Create Radial Charts

Published on November 4, 2015

This post is a continuation of the Creating Interesting Visuals series – click here to read the previous post on preparing and importing data.


You’ll use the new “Stackexchange Daily Activity” dataset to create a calendar heat map and a radial chart.

There are several ways to create a new visual in Arcadia. Here are a couple:

  • Go to “App-> New Visual” and then select “Stackexchange Daily Activity” as your dataset. (Note: Samples should be the connection selected in the sidebar.)
  • Go to “Data->Datasets” and, besides the desired dataset, “Stackexchange Daily Activity,” click “New Visual.” (Note: Samples should be the connection selected in the sidebar.)

Now that you are on the New Visual screen you can make a radial chart.

  1. A new visual always starts as a table viz showing all dimensions and metrics at the row level of the underlying data and shows the first 100 rows. (Kudos to Arcadia for doing this; it is a great way to remind the analyst of how the data is structured.)
  2. Rename the viz “Stackexchange Site Activity Comparison” (click “Edit” beside “Untitled”).image35 image41
  3. Refresh the visual and be sure to click the orange “Save” button.
  4. While we’re here, let’s alias each of the measures so you don’t see the “sum(x)” in the tooltips and legend. Click on each measures pill and then “Alias->Set” and enter the measures name. Let’s call users “New Users” just to clarify that this is new members joining the site.image52

Radials are a good way to quickly compare multiple metrics across a dimension. In this case you are comparing multiple measures of site activity across several websites.

So what can you learn from this radial chart? Here are several findings:

  • Stats (also known as Cross Validated) has the most overall activity, and compared to the other three sites, its activity is pretty balanced. The “Answers” slice is proportionately a little smaller than the other activity. This contrasts with the other three sites, which tend to have more answers per question. We can theorize that this is likely due to the complexity of the questions and answers required on this site compared with the others.
  • DBA (Database Administrators) has almost as many users sign up as stats in the past year. I’d theorize that the greater connectivity between StackOverflow (the original stackexchange site for programmers) and the DBA site causes this. Many users likely join both, and then don’t spend as much time on the DBA site. (We could actually investigate this theory as the User table for each stackexhange site has an account_id that links users across the whole ecosystem; but we’ll leave it as an idea that you can explore if you wish).
  • GIS (Geographic Information Systems) is fairly balanced, although its acquisition of new users is relatively low compared with the others. This may seem this way due chiefly because of DBA’s disproportionate acquisition of New Users.
  • RPG (Role-playing Games) is the smallest of the sites and has a disproportionate number of answers compared to its other metrics. This is likely due to the less technical nature of the subject matter. It also has a significantly high number of comments; this is likely due to a greater need to clarify questions and answers in order to arrive at a “correct” answer.

Creating Interesting Visuals is continued here – Creating a Heat Map