Urban Concentration Suppose the 100 largest cities in the United States in 1920 are ranked according to magnitude (areas of cities). From Lotka,6 the following relation holds approximately:   Here, P...

Urban Concentration Suppose the 100 largest cities in the United States in 1920 are ranked according to magnitude (areas of cities). From Lotka,6 the following relation holds approximately:

Here, P is the population of the city having respective rank R. This relation is called the law of urban concentration for 1920. Solve for P in terms of R, and then find how fast the population is changing with respect to rank.