Introduction to Urban Science: Evidence and Theory of Cities as Complex Systems

several of the more developed ones describe a central market: a point in space where goods are exchanged at a distance from their surrounding production locations.

general set of quantitative regularities, which take the form of scale-invariant relations (power laws), the resulting body of evidence is known as urban scaling.

Many attempts have also been made to explain the gravity law using more fundamental theory,

(4) the larger settlements are, the greater the distance between them, with villages found more closely together than larger cities; (5) the larger the size of settlements, the rarer they become (i.e., there are many small villages for every large city); (6) larger settlements have more functions; and (7) they have more “high-level functions” such

Standard Occupational Classification (SOC)

We would now like to account for the behavior of collective growth in a system of cities and the pattern of relative fluctuations. Specifically, we would like to understand at a fundamental level the slowness and persistence of these deviations from scaling as well as get a handle on their typical magnitudes.

The first effect is a spatialized version of Adam Smith’s famous dictum that “the division of labor is limited by the extent of the market.”

Panel B shows life paths that are constrained and bounded by tubes that express domains of interactions tied to institutions, such as firms or universities,

heterogeneity between people in cities is mostly expressed as differences between places (within a city defined at a kilometer scale) rather than differences within a spatially well-mixed population.