Hard and Soft Closing of Roads Towards Socially Optimal Routing

Recent advances in Intelligent Transportation Systems, navigation tools and personal smart devices enable the development of effective mechanisms for improvement of traffic conditions. We present an information dissemination technique, which provides minimal but the right context to a population and steers the traffic system into a more efficient operational state. Selfish routing in large cities leads to a small group of roads being congested, while the rest of the road network remains underutilized [1], [2]. A routing steering mechanism is suggested, where we homogenize the traffic distribution by selectively disseminating information about the unavailability of certain roads, based on simulated outcomes of their closing. We demonstrate that the full removal of some road segments from the network can redistribute traffic in a socially beneficial way. We identify the most harmful roads and quantify their negative effect on the system. Furthermore, we introduce the concept of soft closing. Instead of informing the whole population to avoid a certain road, we inform only a portion of the drivers, further improving the network utilization. We use the city of Singapore as a case study for our traffic assignment model which we calibrate and validate using both survey and GPS tracking devices data.