"Review of models combining traffic assignment and signal control"

The author reviews a class of models that combine equilibrium traffic assignment and intersection control into a single analysis framework under the assumption of flow-responsive signal settings. The most unique feature of the models is their capacity to consider explicitly the mutual interactions between signal control policies and user route choices--interactions that are usually disregarded in ordinary traffic assignment models and in everyday traffic engineering practice. After describing the combined traffic assignment and control problem, and reviewing alternative formulas and solution algorithms, a discussion is presented on the possible approaches to modeling the various types of link interactions that emerge from the combined use of intersections by competing traffic movements. The author addresses important conceptual issues and implementation aspects, including potential policy implications. The key finding of the survey is that, while the theoretical properties of combined traffic assignment and control models have been extensively studied for two decades and are now well understood, a lack of empirical results and real-world applications are evident, which is necessary to promote the transfer of this modeling approach from research to professional practice.