Skip to main content
Open Access Publications from the University of California

The Relationship Between an Option Space and Drivers' Indecision


A traffic signal is a substantially different traffic sign compared with othe traffic devices. The uniqueness of traffic signals is manifested in their displaying an alternate message and not a constant one. The transition period from one message to another creates a decision problem for drivers. An inappropriate decision might create a risk of a rear-end collision. This article presents a disaggregate behavioral model for drivers' decision when the green light ends. It is demans trated, and supported by field data, that a large option zone increases the indecision of drivers. The increase in indecision creates a greater risk of rear-end collisions, as experienced at many intersections. The influence of distance from the intersection and of approach speed on drivers' decision is examined through the model.

Main Content
For improved accessibility of PDF content, download the file to your device.
Current View