Despite the couple of games that the Mariners and Athletics played in Japan last week, Major League Baseball is calling today the opening day of the season. As a lifelong fan of the defending World Series champions, the Boston Red Sox, I am excited for the start of the season. Where do Red Sox fans live? How far does the fandom spread? And what’s the disbursement of fans for the other Major League teams? Those questions can be answered by looking at SeatGeek’s interactive map titled Where do MLB Fans Live?

Where do MLB Fans Live? is an interactive map that shows which teams are the most popular teams in each county in the United States. A few things found through the map were not surprising at all. For example, every county in Maine and New Hampshire the Red Sox are the most popular team. And a few things revealed in the map did surprise me. For example, growing up in Connecticut I always felt like the state was evenly divided between Yankees and Red Sox fans (with a few oddball Mets fans sprinkled in), but according to this map the state is predominantly a Red Sox state.

There are a couple of flaws with the data interpretation on SeatGeek’s Where do MLB Fans Live? The data is drawn from analyzing the behavior of shoppers on SeatGeek. So it is entirely possible that a team is more popular in a county than another but the fans of that team are more active shoppers. Another flaw is that the map only shows which team is most popular in the county but doesn’t show how much more popular it is than another team. So it is possible that a county could be split 49% to 51% in favor of one team. Most statisticians would not consider that difference to be significant.

Applications for Education
I’m sharing this map because I think that it could be a good tool for introducing students to the nuance of data interpretation and manipulation. The map could also be used as a model for how to represent data through maps or through infographics.

H/T to Maps Mania.