In this study, we tested 41 drivers in right-turn timing judgment while looking at an oncoming vehicle from a stationary car in an intersection.

We obtained “the hasty judgment rate” as the ratio of drivers who reported hasty judgment under different kinds of traffic conditions. The hasty judgment rate changes with the following factors:​

1. speed of an oncoming vehicle,
2. “the time-gap” (gap in time units) for the oncoming vehicle to arrive at the intersection,
3. the category of the oncoming vehicle,
4. daytime and nighttime.

Furthermore, we conducted the gap acceptance practice for 27 car drivers to reduce the hasty judgment rate.