Visualizing the Racial Divide

| November 17, 2011

Jim Vallandingham, a software developer who works for Stowers Institute for Medical Research as a Programmer and Data Analyst recently created this thoughtful data art project called Visualizing the Racial Divide. Seeking to visualize the impact of segregation in US cities in a unique way he writes, “I wanted to come up with a more visual and perhaps more visceral way to show these racial divides and how they serve as real boundaries in and around communities.”

The Vision

Rather than following the 3-D style of the Chloropeth maps made by Salon (which Vallandingham points to on his blog), he uses force-directed maps to show (through this “visceral” experience) how segregation in a city can “break it apart.” In this sense, the data is presented as more of a summary, with little emphasis on numerical or locational precision. “Certainly it is not really meant to provide exact numbers,” he writes. “These maps only encode differences between white and black populations.”

After choosing cities from William Frey’s ranked list of black-white segregation in cities based on census data, he encoded connections between tracts based on disparities in racial make-up. Similar tracts have shorter connections, while longer connections exist between tracts that have a sharp change in white and black population proportions. Thus, the short connections don’t move the map much but the long connections create rifts that force areas apart. In some ways this mimics the real-world effects of racial lines, writes Vallandingham. Click on the image to see the actual visualization.

By contrast, click on the images below to see Salon’s maps.

Data vs. Story

Vallandingham’s explanation of his own project is strikingly humble, and he’s eager to hear responses to his work. Lucky for him, Flowing Data subsequently put the question out to its readers: Which maps, Jim’s or Salon’s, do you think work better to show the racial divide? Responses, which you can read here, include one from Derek Watkins (we featured his own map we here), who writes,

I think…the data (raw values) are more clearly depicted by the choropleth maps. That being said, any thematic map (or visualization) provides a subjective angle on some story that emerges from the data, and I think that’s where these maps really shine – as a storytelling device. I feel the same way about cartograms. I may be in the minority here, but often I’d rather maps ‘lie’ to me flamboyantly/overtly instead of hiding it underneath some sneaky class breaks on a choropleth. If I want to get at the data itself I’d prefer to just see the tables.

The project is certainly a unique look at how data, when presented just right, can shed light on more complicated stories (and histories) in a figurative way. And, such presentations could certainly make data come alive (particularly for younger students) in ways that textbook histories cannot.