Ian W passes along this article from Scientific American that shows “urban travel patterns worldwide are, in fact, remarkably predictable regardless of location—an insight that could enhance models of disease spread and help to optimize city planning.”
The law is an inverse square relation between the number of people in a given urban location and the distance they traveled to get there, as well as how frequently they made the trip.
Or to use an example: the number of people coming from two kilometers away five times per week will be the same as the number coming from five kilometers twice a week.
The researchers analyzed data from about eight million people between 2006 and 2013 in six urban locations: Boston, Singapore, Lisbon and Porto in Portugal, Dakar in Senegal, and Abidjan in Ivory Coast. … The researchers found that all the unique choices people make—from dropping kids at school to shopping or commuting—obey this inverse square law when considered in aggregate.
One explanation for this strong statistical pattern is that traveling requires time and energy, and people have limited resources for it. “There is something really very fundamental at play here. Whether you live in Senegal or in Boston, you try to optimize your day,” says study lead author Markus Schläpfer of ETH Zurich’s Future Cities Laboratory in Singapore. “At the core is the effort that people are willing to invest collectively to travel to certain locations.”