The relationship between the discrete and continuous models for the combined distribution and assignment problem is presented. In particular, it is shown that, under certain conditions, the classic continuous flow formulation of the combined distribution and assignment problems can be viewed as...

The problem of missing data in the base (calibration) year is of major importance when applying the gravity model in transportation planning, because base year data are used for calibration of the model. In this article, this problem is tackled by solving an optimization problem for the...

An optimizing model which minimizes average generalised trip cost subject to constraints on the entropy was given in a previous paper. In this note the model is placed in a planning context.