Data VisualizationTips, Tricks, and Pitfalls

Bob Scopatz

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Number of Graphs Plotted in Each Century

First Data Plot: circa 1644

Minard 1869

Modern Times: And Traffic Safety

• There are 100s of types of graphs• Most of what we see is 3 types:

– Bar– Line– Pie

• Graphic Tools are Good and Bad

Bad Example: USA Today

Another Bad Example: USA Today

Pitfall #1: Art over Information

• Tufte: Chart Junk• Visual elements that convey nothing• Or worse…confusing/contrary information

Tip: Not all Graphic Artistry is Bad

Trick: Use Dimensions Meaningfully

• Size (Height, Length, Width, Depth)• Color• Shape• Fill (pattern, transparency)

• NOTE: Extra time looking should be rewarded by more information extracted

Pitfall: Excel Options

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YesNo

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Tip: Visual Comparison

Tricks

• Small Multiples• Animation

Small Multiples

Animation

Free Tools!

• Google Public Data Explorer

• Data Scene (Express Version)

Google Public Data Explorer

• Animations• Bubble Charts• Add own data!

Data Scene (Express)

• Commercial Product• Free version• Limitations in

Free Version• Animations

Or…Build it Yourself