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How I Made That: National Dot Density Map

Mapping one dot per person, it’s all about putting the pieces together.

The How I Made That series describes the process behind a graphic and includes code and data to work with.

In mapping one dot per person, I used code snippets from a combination of three tutorials. One for Alaska and Hawaii layout, one for dealing with multiple shapefiles, and one for dot placement.

In my final maps, I drew one dot per person and color-coded the dots by race, based on block group-level data from the Census Bureau.

Here’s how I put the pieces together.

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About the Author

Nathan Yau is a statistician who works primarily with visualization. He earned his PhD in statistics from UCLA, is the author of two best-selling books — Data Points and Visualize This — and runs FlowingData. Introvert. Likes food. Likes beer.