University of California Transportation Center

In this article, the authors use field data from a 5-lane freeway in Oakland, California, to demonstrate the concept that detailed information can indeed be recovered from freeway detector data with a simple visualization tool. By using the oblique plot technique, a "moving bottleneck" can be detected and its regularities quantified. As a result of this new technique, insights can be gained into wave propagation in traffic, bottlenecks caused by freeway merges bottlenecks caused by off ramps, and transition zones at the back of freeway queues.