Tuesday, August 4, 2015

Mapping the Spread of U.S. Baby Names Over the Past 100 Years


There was a clear north-south divide up through the 1970s, when this adorable geography began to scatter.
Sometimes science gives us a wealth of methodical analysis and informed observation with the potential to improve life for a great many people, if only it weren’t ignored by those who mistake their personal opinions for knowledge. And sometimes science gives us some super cool maps of baby names.
At least one of these descriptions fits a fun new study tracking the spread of newborn names across the United States over more than a century. The Rome-based research team behind the effort, recently published in PNAS, gathered annual statistics on popular baby names for each gender from the U.S. Social Security Administration from 1910 to 2012. They then measured which states shared more names in common than others.
What they found were several patterns of pretty clear geographic divides for most of the past 100 years that suddenly fractured beginning around 1970; here’s the takeaway:
In the beginning of the 20th century states were divided into a group of northern states and a group of southern ones, and this separation remains stable across many years. This structure suddenly breaks down in the last decades of the 20th century, and a new configuration of groups emerges.
And here’s what they found in the form of colorful maps:

States with similar colors for a given year used similar baby names; above, the distribution for 
newborn girls. (PNAS)
The above map cluster shows state-by-state similarity in baby girl names across America. The closer two states are in color, the more names they shared in common. So in 1910 we see some pretty clear clusters forming, especially in the Northeast, South, and Midwest. By 1940 and into 1960, there’s a very stark north-south divide in baby names, with the Northeast veering off its own way. (For the record, in 1960, the five most common girl names were Mary, Susan, Linda, Karen, and Donna.)
By 1975 this adorable latitudinal divide was starting to shift, with the likes of California, Illinois, and New York aligning more closely with the South, and little clusters of uniquely named cuties emerging here and there. The South and Northwest held strong together through 1990, but by 2000 we see a great deal of variety across the country. (The top five girl names in 2000? Emily, Hannah, Madison, Ashley, and Sarah.)
A similar pattern is found in the map series for boy names:

The distribution for newborn boy names, above, generally follows the pattern of girl names. 
(CityLab via data from PNAS)
Once again we see a clear north-south split up through 1960, even holding mostly true through 1975, though by then parts of the Northeast have started to go their own wee ways. By 1990, the Northwest and the South are the only geographic areas to retain strong similar patterns, and by 2000 the shift away from national name uniformity is even more powerful, especially along the East Coast. Top five boy names in 2000, for those keeping score at home: Jacob, Michael, Matthew, Joshua, and Christopher.
(You can watch animations of the entire 1910-2012 girl and boy name map sequences here.)
So what is it about the 1970s that saw Americans start to balkanize by baby name? The study authors punt on the question, though they do borrow an explanation from another recent report with similar findings: “the deep cultural transformation that occurred in the United States after the Vietnam War.” Given that name patterns often follow pop culture—see: the rise in the name “Trinity” followed the release of The Matrix—it’s also likely that new trend lines arose as mass media became both more diverse and more accessible.
And let it be known that the researchers maps did, in fact, have a legitimate empirical purpose to their work: to “demonstrate that cultural evolution of society can be observed and quantified by looking at cultural traits,” with those traits in this case being baby names. Cribward and upward with the sciences.