Any day is a good day for a map of predominant commercial chains. For The Washington Post, Kevin Schaul and Jaclyn Peiser show the most common grocery owners, creating territories within the United States. Albertsons, also the owner of Safeway and Vons, dominates the northwest, and Walmart has its hands just about everywhere, but especially owns a stronghold on the midwest.
On methodology:
Grocery store addresses comes from OpenStreetMap, a community-driven effort to populate maps with location data. The Post pulled locations in the United States identified as supermarkets, as well as Walmart, Sam’s Club, Target and Costco. The map visualizes the influence of the nearest grocery store locations using a k-nearest neighbor analysis that falls off as the distance to a stores increases. Grocery stores with unique names were excluded from this analysis.
There is also a search feature that lets you see the common stores in your county, beyond the leading owner.
