Effect of Signal Control on Bimodal Travel Time Distributions

Abstract

Vehicles traveling along interrupted flow facilities often exhibit travel times with bimodal distributions. The characteristics of these distributions have been studied extensively in the literature, yet the effect of signal control on bimodality have received little attention. Most researchers theorize that the slower group experiences signal delay while the faster group does not. We investigate the effect of signal control on bimodal distributions, specifically the difference between average travel times of two groups of vehicles. Testing is performed in simulation and compared against field results of both sampled data using Bluetooth sensors as well as non-sampled data from the NGSIM vehicle trajectories. In coordinated corridors with platooning, we find that red time is a strong indicator of gap between average travel times.

Method for the Annual Accuracy Assessment of Freeway Travel Time Systems

“…For example, Google Maps started using prediction capabilities in late 2015 (Kelareva, 2015). Although some ongoing work is seeking to evaluate the accuracy of real-time and predicted private-sector travel times (Goodall, 2016), no results were available at the time of this writing.…”