Examining Sensitivity of Impact of Taxi Traffic on Capacity and Delays at Urban Road Sections

This paper examines the influence of taxi behavior on urban traffic conditions. Using computer simulation and the Taxi Equivalence Factor (TEF), a concept similar to the passenger car equivalents for heavy vehicles, the impacts of taxi traffic on the capacity, and delays at urban road sections is quantified. The taxi equivalence factor is based either on capacity or on delay. Through extensive simulation analysis, the effects of various traffic parameters on the magnitude of the TEF were examined. The results suggest that the TEF is significantly higher for one-lane roads than it is for two-lane roads. Further, the capacity based TEF takes on very low values, while the delay based TEF takes on values that under specific traffic conditions may approach 2. This indicates that the presence of taxis does not seem to affect road capacity, but it significantly affects traffic delay. In any case, the maximum TEF values are found, as expected, when flow approaches capacity.