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Thanks to the news this week, I spent some time over the last few days grappling with a question that many, many people have thought about before me: & #39;what& #39;s a suburb?& #39; and what& #39;s our poll result for & #39;suburban voters?& #39;
Our polls use a variety of different geographical variables in different contexts: census block group density, made up regions like & #39;philly suburbs& #39;, census-defined metro areas, or the NCHS urban-rural scheme. None obviously offer a consistent definition of & #39;suburb& #39;
The best definition may vary on the purpose. But colloquially, I think that when people refer to the suburbs of & #39;x& #39; city, they pretty explicitly do not mean any voters within central city & #39;x& #39;, regardless of density, and there are good political reasons to care about city limits.
So this certainly helps identify areas that aren& #39;t suburban, and in our last national poll, voters who live in the & #39;central city& #39; of a metropolitan area (and for, say, the NY-Newark-Jersey City MSA, that& #39;s anyone within city limits of any three), Biden led 64 to 24 percent.
Though easy enough, this definition of & #39;urban& #39; does leave something to be desired: there are plenty of & #39;central cities& #39; that I& #39;d say are part of the suburbs, like Alpharetta, GA.
There are also many tiny MSAs: Do we really want Dothan, AL as urban?
https://en.wikipedia.org/wiki/List_of_metropolitan_statistical_areas">https://en.wikipedia.org/wiki/List...
There are also many tiny MSAs: Do we really want Dothan, AL as urban?
https://en.wikipedia.org/wiki/List_of_metropolitan_statistical_areas">https://en.wikipedia.org/wiki/List...
One option here would be to limit ourselves only to central cities of a certain size (hoping to, say, keep SF and OAK but lose Alpharetta or Waukesha in ATL/MIL). This might also help with the small MSA problem. Still worth investigating.
On the other end of the spectrum is the challenge of delineating suburban and rural. It& #39;s easy enough to say the non-metropolitan counties are rural. But there are many metropolitan counties that are pretty rural, and there are certainly indisputably rural parts of metro counties
Here, the census does offers a possible solution: & #39;urbanized areas,& #39; where the census generally considers non-urbanized areas to be & #39;rural.& #39; I think this does a pretty good if imperfect and maybe outdated job of pulling out rural areas from MSA counties https://gis-portal.data.census.gov/arcgis/apps/MapSeries/index.html?appid=7a41374f6b03456e9d138cb014711e01#:~:text=The%20Census%20Bureau%20defines%20rural,rural%20based%20on%20this%20definition">https://gis-portal.data.census.gov/arcgis/ap...
Another option is some kind of population density floor, where a block group outside of the central city in an MSA county would be suburban if its population density is greater than x/sq mi.
That said, the urbanized area definition is close to many plausible density floors
That said, the urbanized area definition is close to many plausible density floors
I& #39;m fairly satisfied with this end of the definition, though there are some high growth suburbs in the Sun Belt sprawling into 2010 & #39;rural& #39; areas and there are rich mansion zones that aren& #39;t urbanized by census standards, tho very few people there
If we leave our definition of suburbs here--census-defined urbanized areas outside of any central city in any MSAs--then the last NYT/Siena result for suburbs is Biden 50, Trump 34.
The biggest opportunity for improvement would be to see if there& #39;s a smart way to make the Alpharetta/Waukesha type & #39;central cities& #39; count as suburbs, based on some kind of population floor. I& #39;d guess it won& #39;t have a huge effect, but worth seeing if there& #39;s a non-arbitrary option
A secondary opportunity is to see if there& #39;s a way to grow our suburban definition to include post-2010 suburbs (possibly based on new ACS density data) or tiny non-urbanized rich enclaves (tough, as the pop density is quite low). I& #39;d guess this isn& #39;t worth it or workable
Of course, every definition has shortcomings. And depending on the purpose, another may be more appropriate. But if I get one single, national standard definition of a & #39;suburb& #39; for polling, I think something like this is most consistent with how it& #39;s used politically
The most coherent critique, IMO, is that this is a very industrial-northeast focused definition of a suburb. There are many Sun Belt metros where the city-limits are basically coterminous with the whole urbanized area, so we would have few no & #39;san antonio suburbs& #39;
The way around it is to use a density/development based definition, which would make almost all the Sun Belt metros & #39;suburban.& #39; I think this vision has merit and it also correlates well with vote choice.
OTOH, this remedy could put big chunks of Seattle, Queens and Detroit and wherever into the & #39;suburbs.& #39; And for me that& #39;s kind of facially unacceptable, at least for this kind of generalized purpose. In this context, I& #39;d settle for calling San Antonio urban.
And we can drill into these distinctions when appropriate. Central city block groups with a density >10000 sq/mi are Biden 74, Trump 14 in our poll; those under that are Biden 59, Trump 28.
