Fig 4. Events and time intervals used to evaluate safety of street crossing timing.

Four possible combinations of the participant’s GO call (cyan circles), the onset of the WALK sign (the green circle) and the time when a near lane parallel traffic surge being confirmed (magenta circles) are shown in a WALK phase delineated by the onset of the WALK sign (WALK On) and the onset of the DON’T WALK sign (DON’T WALK On). (A-D) illustrate the four possible time sequences of the WALK On, Surge Confirmed and GO events.