PURPOSE The objective of this paper is to provide a new method for estimating crash rate and severity simultaneously. METHODS This study explores a Heckman selection model of the crash rate and severity simultaneously at different levels and a two-step procedure is used to investigate the crash rate and severity levels. The first step uses a probit regression model to determine the sample sel...

Quantifying the effects of crosswalk length and signal timing on pedestrian walking speed is an important requirement for providing a rational safety assessment and improving existing operational policies at signalized intersections. This study investigates the effects of pedestrian green time (PG), crosswalk length and pedestrian crossing direction on pedestrian walking speed at signalized cro...

Signal timing and lane allocation are most important settings at signalized intersections to control the operation. Efficiently operated traffic signals and reasonably designed lane markings can reduce congestion and bring about significant payoffs in time and energy benefits. The design of signal timing plan and lane allocation pattern should be complementary to each other; however, existing r...