After consulting on a project evaluating the housing preferences of Millennials, I decided to dig deeper independently and see which neighborhoods my fellow Triangle Millennials are calling home. Inspired by Dustin Cable's famous Racial Dot Map, I visualized the population density of specific age cohorts in Durham and Wake County using a dot density map.
I began with population data from the 2009-2013 American Community Survey, extracted at the block group level. I classified the population in five groups: ages 18 to 20, 21 to 24, 25 to 29, 30 to 34, and non-Millennials. While I could have created a map that would render the data on-the-fly, I chose to use tile layers for quick rendering and smoother zoom transitions. I created and styled these tile layers in Mapbox Studio Classic and customized my map to toggle a non-Millennial layer using Mapbox.js. The resulting map clearly highlights neighborhoods with high concentrations of Millennials.
This project was purely recreational – a fun way to get to know Mapbox using data I had on hand from earlier research. It was a great learning experience and I hope to use these techniques on projects to come. Future iterations, however, would make an effort to restrict the dots to residential areas by clipping out parkland, bodies of water, and highways. (I'm afraid I drowned quite a few Millennials in the Neuse river this time around!)