Passenger travel demand models: factors underlying work & study related travel

The issues dealt with in this paper can be set against the broader frame of reference referred to as transportation demand analysis. The paper intends to identify the factors underlying transport demand and to explain how they help determine it in order to estimate its changes in time and space. Considering the shortage of periodic information on how people travel with sufficient territorial detail, this paper combines the results of various surveys, not only to take account of individual and environmental variables - therefore related to the characteristics of the area in which the demand is originated - but also in order to use, jointly, variables found through different surveys. We estimated at regional level the numbers of commuters using non parametric models.