## Using a Motion Chart to Visualize Data

While motion charts are not new, I just learned about them and I thought they would be something that faculty can use in their classes to help students see and understand certain concepts in their classes.

### Motion Chart

A motion chart, at least as it’s used in this post, is a bubble chart that can be controlled by the viewer, not the creator.  It allows the viewer to visualize multiple dimensions of the data.   These dimensions are shown by the bubble size, color and position on the chart over time.  Here is an example from Kwantu.com:

• Vertical (Y) axis – Percentage of HIV exposed infants given ART for PMTCT at birth
• Horizontal (X) axis – Percentage of HIV+ women receiving ARVs for PMTCT
• Bubble size – Health expenditure per capita (current US\$)
• Bubble colour – Pregnant women receiving prenatal care (%)
• Time – Years

According to JuiceAnalytics, “modern-day motion charts were developed by an organization called GapMinder as part of a product called Trendalyzer.  Hans Rosling, one of the founders of GapMinder, popularized the motion chart visualization in a much-admired TED Talk.”

### What are they good for?

What I think sets this chart type apart from other charts in either Excel or Google Sheets, is that they are interactive.  The end-user can use the sliders to change time and the dropdown menus to change the data parameters shown.  It allows the viewer the control over what they see to help them better understand the data and to work with it in multiple ways.  Any discipline that uses statistical or relational data over time can benefit from a motion chart (political science, sociology, history, education, biology, etc.).

### How do you make one?

With Google Sheets, part of CofC’s Google Apps for Education (G-Suite), you can make a motion chart in just a few easy steps.

1.  Column A (first column) should contain the data you want to track.  In the example above, it is Country.
2.  Column B should contain the time data and should be sorted/grouped by time.
3.  Column B also needs to be formatted as a date, not text.
2. Highlight all the data in the table and click on Insert > Chart.
3. Choose the Chart Types tab.
4. Scroll to the bottom under Other and choose Motion Chart.
5. Click Insert.
6. Once it’s inserted you will be able to change the X/Y access, use the scroll bar to slide through the times and the boxes on the right to narrow the data seen.

BONUS — You’ll also notice, in the upper right corner, that you can choose between a bubble chart, bar chart, or a line chart.

### Let us know

If you try this let us know how you are using it in your teaching or with your students!  We love to hear from faculty.