--- In

carfree_cities@yahoogroups.com, "J.H. Crawford" <mailbox@...> wrote:

>

>

> For instance, if one city is 10 times as populous as another one, does it need 10 times as many gas stations? No. Bigger cities have more gas stations than smaller ones (of course), but not nearly in direct proportion to their size. The number of gas stations grows only in proportion to the 0.77 power of population. The crucial thing is that 0.77 is less than 1. This implies that the bigger a city is, the fewer gas stations it has per person. Put simply, bigger cities enjoy economies of scale. In this sense, bigger is greener.

>

> The same pattern holds for other measures of infrastructure. Whether you measure miles of roadway or length of electrical cables, you find that all of these also decrease, per person, as city size increases. And all show an exponent between 0.7 and 0.9.

>

>

Fascinating research. I'm interested in some follow-up research -- what is the effect of geographic area on resource efficiency? The population of Northeast Ohio/Greater Cleveland area has been fairly constant since the 1950s, but that population is now spread over a much larger area. What does math tell us about that process and the efficiency of our allocation of resources?

And what does math tell us about the evolution of other rust belt cities, for example, many of which had large populations that then sprawled outward and ultimately collapsed (Detroit's core) and stagnated or declined (the greater Detroit area) population-wise vs. the cities that have grown in population and sprawled simultaneously -- Atlanta, Phoenix, etc.

Somewhere in there maybe some brilliant mathematicians will take a look at the effect of the mass-adoption of the automobile on city design. I suspect that we will find mathematical support for the increased efficiency of a carfree city.