Results are presented of a study which examined drivers' ability to interpret and use information broadcasts about road traffic incidents to find alternative routes. The experiment was designed to simulate some of the characteristics of an operational dedicated traffic broadcasting system by presenting drivers with messages concerning a major, though hypothetical, incident along the route they were travelling. Two kinds of traffic message were compared: one containing details of a recommended alternative route, the other merely informing drivers of the presence of a road blockage. All messages gave details of the nature, location, duration and expected delays resulting from the incident. The main criterion adopted for assessing message effectiveness was the proportion of drivers who successfully avoided the blockages described in the broadcasts; a secondary analysis evaluated and compared the generalised costs of successful diversions. Overall, three-quarters of the journeys resulted in successful diversions. Drivers given diversion advice were generally more successful than other drivers although their diversion route costs were about the same. As expected, knowledge of the local road networks contributed to successful navigation round the blockages. (Author/publisher)
Abstract