Hello, readers! Liz DiLuzio here, Lead Curator of AEA365. We didn’t have the heart to leave Pi Day unacknowledged, so here’s a special second release of the day. It comes from our own Ann K. Emery, here to talk to us about pie charts and their alternatives.
It’s March 14th, which means… Happy Pi(e) Day!
Hi, it’s Ann K. Emery, dataviz designer at Depict Data Studio.
Recently, I was working with an organization to improve their report.
The draft had a page of pie charts.
Pages, actually. One per school times dozens of schools in the project.
(These are made-up numbers, but you get the idea.)
I know what you’re thinking: “Pie charts are evil! Just delete them!”
Novices avoid pies.
Vizards embrace them (sometimes; here’s when pie charts are okay).
More importantly, vizards know what to use instead.
Let’s transform from novice to vizard when it comes to dealing with pages and pages of pie charts.
Page of Pies
I only use pie charts for two-slice binary data, and when I’m looking at a single pie.
This dataset had 4-slice ordinal data, and we’re asking the viewers to compare across multiple pies.
Next, I went back to the basics: A table.
I used percentages instead of numbers since we’re dealing with a “big n” (bigger than 100; my cutoff for choosing percentages over numbers).
Then, I added a heat table to draw attention to larger numbers.
It’s not terrible. And it might actually be perfect for the visual appendix of a report.
Let’s try some more vizzes.
The researcher-turned-dataviz-designer in me wanted to try stacked bars. These used to be my go-to chart.
There’s a lot going on.
Sometimes, 0% of survey respondents chose an option. Stacked bars can’t show zeros.
I don’t love switching between white and black ink. Consistency is such a value-add. But, we often have to switch ink colors to make sure our graphs have enough color contrast.
Small Multiples Bars
Small multiples bars can show zeros. (Well, the label is legible next to the absence of a bar.)
We don’t have to switch back and forth between white and black ink.
There’s plenty of white space; it’s not as dense as the stacked bars.
We can see how the distribution has shifted over time.
I didn’t want to love this one…
I tend to have way too many bar charts in my draft datavizzes.
But, it’s my favorite. 🙂
When I was brainstorming ideas in my head, I thought this was going to be the winner.
The small multiples bars showed the distribution side by side; this option places them on top of one another.
Overlapping designs can be powerful when we want to see how the numbers have shifted over time.
But… it was tough to fit on a page. I tried making smaller charts, but the Never Seldom Sometimes Often labels tilted themselves diagonally.
I never shrink font sizes to get everything to fit onto the page. Too many people wear glasses.
With more editing time, I probably could’ve figured out how to arrange everything on the page better.
Behind the Scenes
Want to continue learning about the pros and cons of each visualization?
Want to see how I arranged my spreadsheet to create these charts?
Let’s explore the viz ideas in more detail:
Download My Spreadsheet
Bonus! Download the dataset and click through the spreadsheet yourself: https://depictdatastudio.gumroad.com/l/page-of-pie-charts
You’ll see how I made one template and then populated it with each school’s data.
This isn’t an exhaustive list. What additional ideas do you have for revamping the page of pies? Which viz idea was your favorite, and why?
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