New Estimates of Gravitational Attraction by Linear Programming

Abstract

This paper uses data for intercity air‐passenger travel to derive a set of general propulsion and attraction factors for twenty‐five large U.S. cities. The paper develops a new way of examining the linkages between flows and nodal attraction. The technique is to assume that the flow data fit a simple gravity model, and then linear programming is used to maximize the consistency of the endogenous propulsion and attraction with the flow data. Various linear models are used to determine the pattern of urban attraction factors that are consistent with the gravitational flows. Linear programming as well as goal programming models are used to develop a set of analyses linking flows to urban hierarchies. Suggestions for further extensions of the method to address substantive issues of urban systems analysis are also provided.