Recursive Model System for Trip Generation and Trip Chaining

A model system is developed to describe both trip generation and trip chaining in a coherent manner. A recursive structure is adopted to represent the generation of trips for different purposes, and the number of trip chains is expressed as a function of the numbers of trips by purpose. The model system offers theoretically consistent coefficient values and quantifies the relationship between the number of trips and the number of trip chains, and can be used in the conventional forecasting procedure in place of home-based and non-home-based trip generation models. This model is applied to examine how trip chaining patterns vary across sample subgroups. The results indicate no significant variations in trip chaining behavior across car ownership subgroups. It is inferred that car ownership influences household trip generation, but given the number of trips generated, the number of trip chains is not influenced by car ownership.