Population and employment density functions revisited: a spatial interaction approach

"This article proposes a generalized urban spatial structure and transportation network, and adapts the Garin-Lowry model to simulate both population and service employment densities in this hypothetical, yet realistic, city. The model is solved numerically while varying exogenous factors such as the distance friction coefficients and the spatial distribution of basic employment.... The results are generalized by estimating, via regression analysis, density functions over a large sample of simulated density patterns, pointing to the critical importance of transportation costs and basic employment distribution, and providing a basis for further empirical studies."