How to Create Chord and Flow Charts

Published on November 5, 2015

This post is a continuation of the Creating Interesting Visuals series – click here to read the previous post on Heat Maps


Correlation flow charts and chord charts are used to show movement or some sort of change across two dimensions.

In this tutorial, you’ll use them to explore the quarterly change in Member/User activity levels. You have a hierarchy of Activity into which members are grouped in each quarter in the data source, as follows:

  1. Highly Engaged: asked a question, submitted an answer to a question, and commented.
  2. Responder: submitted an answered to at least one question; may have also asked a question or commented, but not both.
  3. Commenter: commented on a question or answer but did not provide their own answer, or ask any questions.
  4. Disengaged: had activity in the previous quarter but no activity in the subsequent quarter.

Note: Only users who had activity in Q1 are considered in this analysis.

Let’s see how users who were active in Q1 changed.

Correlation Flow Chart

  1. Go to “App -> New Visual” and then select “Stackexchange Shifts” as your dataset.
  2. image38  
  3. Drag “Engagement_Q1” and “Engagement_Q2” from the sidebar onto the dimension shelf. Add “Users” to the measures shelf.
  4. Click “Refresh Visual” and the orange “Save” button.
  5. Next, add two filters. Drag “Site” onto the filter shelf and leave it unselected (you’ll use this at the app level later). Drag “Engagement_Q1” onto the filters shelf, click the pill, and check “Exclude these values” and “Other” (this removes the uncategorized users in the Other group). 
  6. It’s important that the “Engagement_Q1” field is first on the dimensions shelf and is followed by “Engagement_Q2” (we expect things to move left to right through time), so reorder them by dragging the pills around if needed. Add “Active Users in Q1 ——-> Activity in Q2” as a subtitle, and title the viz something like “Correlation Flow Stackexchange Shifts <<Site>>.” Your shelfs and titles should look something like: 
  7. If you want to see the same colors on the chord chart, go to “Settings” on the top right, select the largest color palette on the “Palette” tab, and on the “Marks” tab choose “colors are based on dimension values.” Note: since we are cloning this viz to create the chord chart, we only need to do this once. 
  8. As always, click the orange “Save” button.

Chord Chart (via Cloning)

Next, you’ll create another way of looking at the shifts between these two time periods with a chord chart.

  1. On the correlation flow chart you just made, click the “Clone” button on the top left. This will reopen the same tab as a copy.
  2. Rename the viz from “Clone of Correlation Flow Stackexchange Shifts <<Site>>” to “Chord Chart Stackexchange Shifts <<Site>>” (click “Edit” beside the title).
  3. Click the orange “Save” button.
  4. Under “Visuals” at the top left, select “Chord.” 
  5. You’ll notice that “Disengaged” is so large that it almost obscures everything else that is going on. You can filter this out. Add “Engagement_Q2” to the filters shelf. Click the pill and exclude “Disengaged.” Save the filter. 
  6. Click the blue “Refresh” visual button.
  7. Edit the subtitle to “Users active in both Q1 and Q2 shifts” and then save the viz (orange “Save” button on the top left).

Creating Interesting Visuals is continued here – Creating an Extension Visual