Historical development of activity based model theory and practice

This article discusses the theory underlying activity based (AB) travel demand modelling; the examination of the theory in the first section provides the concepts needed for examining AB modelling approaches. In the last 35 years modellers have attempted to incorporate the insights gained on activity-based travel theory into urban travel forecasting models, with increasing success enabled by the advance of computing technology. The article then mentions a few operational forecasting systems representative of the most advanced practice of their time worldwide. The final section provides a concise summary of important design features of various AB model systems that have been implemented or have recently been designed for planning agencies in the US.