Fallacy of Composition

It is darned hard to make reasonable inferences based on the data we’re getting and, especially, based on the media reports. Keep in mind that most of the people in the national media live in the New York City metro area, the Washington, DC metro area, or Los Angeles.

Roughly one third of all confirmed cases of COVID-19 in the United States are in the New York metro area. We’re not sure why that is. Population density, temperature, the number of people returning from China during January and February, and the behavior of the people, e.g. crowding into subway cars, probably all play roles.

More than one third of all confirmed cases of COVID-19 in California have been in the Los Angeles metro area. The reasons for that are even less clear than for New York. The only two that seem to apply are the number of people coming from China during January and February and behavior.

Composed as it is of parts of Maryland, Virginia, and the district itself, Washington, DC is harder to ferret out. To my eye there actually haven’t been a lot of cases in the DC metro area.

Compare New York and LA with some other places. There have been more confirmed cases in the Bronx than there have been in the ten states with the lowest number of cases put together (Minnesota, West Virginia, Nebraska, Kentucky, Hawaii, Alaska, Oregon, Montana, Kansas, North Dakota). Those states are all over the map but quite a few of them have things in common. The Upper Midwestern states in that list plus a few others are relatively homogeneous, socially cohesive, known for maintaining “social distancing” even under ordinary circumstances, and tend to have low population densities. Hawaii has a warm climate going for it.

Shoehorning a policy crafted for New York City into the rest of the country does not sound like a formula for success to me, especially when you can’t even shoehorn it into New York City. The subway is still running, albeit with a much lower ridership.

Now maybe all that will change. Maybe it won’t.

4 comments… add one
  • PD Shaw Link

    Kevin Drum had an interesting chart comparing deaths per capita across California. To some extent Los Angeles is getting hit worse because of its size, but the rate of deaths is highest in Silicon Valley.


  • Guarneri Link

    “Now maybe all that will change. Maybe it won’t.”


  • steve Link

    Minnesota may serve to confirm Garrison Keillor’s claims about Midwestern Methodists. He did some funny pieces about Methodist ministers and their efforts to make sure they didnt touch anyone.

    PD- His chart comparing the UK vs US is also pretty important I think. If we had an alternate universe with people we didnt care about it would be interesting to have a US where we did nothing vs a US where we did earlier mitigation. The UK gives just a little peek at that. They started with no effort to mitigate than saw their numbers skyrocket. Now they have mitigation. They are still running death rates about twice ours. Will be interesting to see how this tracks out.



  • TarsTarkas Link

    NYC being a national and international travel hub plus being led by a blithering idiot who told people to go about their daily lives weeks after everybody else was shutting down (and still hasn’t shut down the moving sardine cans called subways, ‘cuz it’s the economy, stupid) probably has a lot to do with it.

Leave a Comment