STATED AND REPORTED ROUTE DIVERSION BEHAVIOR: IMPLICATIONS OF BENEFITS OF ADVANCED TRAVELER INFORMATION SYSTEM

Advanced Traveler Information System (ATIS) user benefits are estimated from a survey of commuting behavior undertaken in the San Francisco Bay Area in 1993. Reported and stated responses to unexpected congestion are used to determine the commuters who would directly benefit from qualitative, quantitative, predictive, and prescriptive ATIS information. Under incident conditions, ATIS quantitative delay information may induce about 40% of the commuters to change their route to work, mostly the people with greater diversion opportunities, knowledge of more alternative routes, and lower congestion levels on their best alternative route. The travel time savings achieved by ATIS-induced route diversion (with quantitative information) is calculated and translated into monetary benefits. The value of time used is a function of personal income and of the time savings. The frequency of annual diversion is estimated from the time elapsed since the last incident. The potential annual benefits from ATIS route diversion, applicable to about 40% of commuters in the Golden Gate Bridge corridor, range from $124 to $324 per person, depending on the weight assumed for delay.