Nate Silver has been tracking some heat over a post he wrote last week about the Brookings Institution's study of public transit and access to jobs in metropolitan America. The authors have even gone on record to say that there are fundamental differences between what they studied and what Silver thinks they studied.

(from joiseyshowaa on Flickr)

The trouble, I think, is in the all-too-common interpretation that metro area rankings are lists of 'best' and 'worst'. Silver writes:
The report caught my eye because it came to some surprising conclusions. It ranked the top 100 American metropolitan areas on the basis of “access to [public] transit and employment.” I know that I’ve become something of a New York partisan since moving here two years ago, but I was pretty sure that New York was going to rank somewhere near the top of the list, probably along with Washington, D.C., and Chicago.

This seems really strange... I could fathom New York’s being behind Washington — but it has worse public transit than Tucson and Modesto?
The Brookings study clearly didn't set out to create a list of 'best' and 'worst' public transit systems; and I should hope that the Institution's resources would never be put to such a simple-minded task. Forbes or another magazine desperate for web traffic surely will throw together a haphazard methodology to draw such conclusions.

Unfortunately, the knee-jerk reaction whenever a list of ranked cities gets published is to jump to the conclusion that it means something more subjective than what it does. Last year when I ranked cities by college degree holders per capita, I was doing just that: examining how densely populated cities are with college degree holders. Yet many interpreted the post as a "study of America's smartest and dumbest cities". That's the kind of headline that gets attention; but it's not true to what the numbers actually say.

Point is, you can learn something by comparing cities to each other, but various metrics don't always or necessarily make one city better or worse than another.

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