Using RP/SP Survey To Analyze Travel Behaviors Under Traffic Incidents

As an important component of traffic behavior analysis, it has taken more and more attentions by urban transportation researchers, administrants as well as travelers with the rising of requirements for the travel reliability. The limitation of basic data in the traffic incidents makes the traffic behavior analysis very difficult. New achievement on this area is the Victor L. Knoop’s "Road Incidents and Network Dynamics Effects on driving behaviour and traffic congestion". At present, research in this regard is not much in China. The author focus on the basic data collection and analysis, and tries to study, evaluate the travel decision-making behavior.In this paper, The travelers are divided into two categories:the Preparing-traveler and the Roading-traveler based on the travel behavior theory. Then it establishes their decision-making sets. They are:(cancel the trip, travel with the originally plan, change the starting time, change the travel destination, change the travel path, change the travel modes) and (cancel the trip, wait to cross, change the travel destination, change the travel path, change the travel modes). Based on the behavioral decision theory and decision-making psychology, the travel decision-making process in the traffic incidents is constructed.To introduce the ML (Multinomial Logit) model, the paper describes respectively the fixed and the probability of utility function for the travelers in the traffic incidents based on the utility theory. To design the RP/SP survey programs and tables, the basic principle of the RP/SP survey methodology is applied. Obtaining the foundation data can provide data base for building mathematical models and the follow-up study.At last, the paper uses the approximation method to solve the model with the RP/SP combined data.The research shows that traffic incidents have some effects on travel decision-making behavior. The delay time have a greater impact on the choice of the travel program than other property. The author thinks that this is because people are more sensitive to the delay. When the delay time is uncertain, travelers are more likely to take the risk aversion. This is just consistent with the prospect theory. For one traveler, if the travel purpose is work-related, or shuttling, social interaction, the same severity of traffic incident will cause greater loss. And this reflects in the mathematical analysis with a greater disutility. Even be informed of the traffic incident, most of the travelers also adhere to the established travel plans.