Optimal Spatial Interaction and the Gravity Model

1 The Transportation Planning Process -- 1.1. Goal formulation, generation and evaluation of alternatives -- 1.2. Descriptive approaches -- 1.3. Optimizing approaches -- 1.4. Welfare theory and measures of efficiency -- 1.5. The use of existing traffic patterns in the planning process -- 1.6. Outline of the paper -- I On Entropy -- 2 Entropy as a Measure of Dispersion -- 3 Some Comments upon Entropy Maximizing -- II The Doubly Constrained Trip Distribution Problem -- 4 A Model for the Constraints -- 5 The Objective Function and Our Minimization Problem -- 6 The Gravity Model as the Optimal Solution of the Entropy Constrained Aggregate Linear Program -- 7 Sensitivity and the Dual Program -- 8 Interactivity and Entropy -- 9 Benefit Measures and the Gravity Model -- III Modal Split and Assignment -- 10 Modal Split -- 11 Assignment to the Network -- IV Maximizing Total Utility -- 12 An Utility Approach to the Original Trip Distribution Problem -- 13 Entropy Constrained Aggregate Linear Program -- References.