Finding the Heart of the Kansas City Metro Area Determining the "Centroid of the Polygon," or Something Like That
Published November 6th, 2019 at 6:00 AM
Above image credit: Every decade, the U.S. Census uses population estimates to determine where the balance point – or "mean center" – is on the map. (Library of Congress)Looking at a map of the Kansas City metropolitan area, would you be able to point to the mean center of the population?
The U.S. Census Bureau defines the “mean center” as the “balance point” of an area. Imagine a life-sized paper map of the region. The balance point is where a group of people could balance that map if it were lying flat.
The U.S. population has one, calculated in the 2010 Census, and it is located nearly four hours away from Kansas City in Plato, Missouri.
So what’s the Kansas City metro’s balance point? Before reading further, take a quick guess. Is it downtown? Overland Park?
When Brian Reamer, a 25-year-old credit analyst at Commerce Bank and a graduate student, tried to pinpoint the geographic location, he couldn’t find anything. So, he asked curiousKC to find the answer.
Reamer said he initially wanted to learn the best spot in Kansas City to attract talent for businesses, but then his question evolved.
“I’m interested in business and economics. What would be the average center of (the metro’s population)? That’s what got me thinking,” Reamer said.
With the help of Tim Victor, a GIS expert at the Mid-America Regional Council, we zeroed in on a location—near 56th Street and The Paseo.
As it turns out, Victor had never before looked into this fact about the metro area. To find the answer, he used a software platform called ESRI. His team used American Community Survey data from the U.S. Census Bureau, which splits the Metropolitan Statistical Area into smaller geographies – one of those is called the block.
“At that block level, and those are polygons and cover the entire metro, we took the centroid of the polygon, and used that as the center,” Victor said.
There were about 63,000 points for the blocks, so they input those and weighed them by the population. Enter that into ESRI and voila, the mean center location.
Near that intersection sits a church that was built in the 1950s, now called St. James United Methodist Church. It’s led by senior pastor Emanuel Cleaver III, who has been there for a decade.
When he found out his church is near the metro area’s balance point, Cleaver was quiet for a moment and then uttered, “Oh, wow.”
Cleaver added: “(This fact) may mean that we develop a campaign and (use) this information that we’re right in the center of it all.”