Variability of Travel Time, Users’ Uncertainty, and Trip Information

Abstract

Travel time saving plays an important role in the socioeconomic studies of the profitability of transport projects. This paper presents some parts of the studies performed in collaboration with SETRA, a department of the French Ministry of Transport, on the economic evaluation of operating roads. The paper includes four main parts. The first includes a description of how travelers’ decisions are influenced by the variability of travel time. The statistical analysis of the recorded travel time on a motorway in île-de-France, France, is developed to quantify the variability of travel time and to measure its magnitude. The second section is devoted to developing the methodological framework to capture the safety margin considered by travelers in their trip-making behaviors. A model is formulated to reflect the behavior of the traveler before making a trip. This model highlights the effect of each travel component, the mean of the travel time, the level of variability, and the safety margin chosen by the traveler before traveling. The third section extracts the optimal safety margin that minimizes the cost of the total time allocated to travel. The last section of the paper is devoted to some algebraic manipulation to characterize the features of the output if the variability of travel time in the economic evaluation of transport projects is incorporated. An expression is also given for the gain that operators bring when they reduce the variability of travel time or reduce the uncertainty that travelers feel by providing them with information.

Route Choice Model Considering Generalized Travel Cost Based on Game Theory

“…Travelers are paying more attention to the emission problem in route choice besides the consideration of travel time and its fluctuation, because of the aggravation of the energy crisis and the pressing need of environmental protection. It is the ideal goal of travelers to reduce emission, decrease travel time, increase reliability, and so forth [14]. However, these goals often lead to contradiction and conflicts.…”

Travel time cognition: Exploring the impacts of travel information provision strategies

“…Intelligent transportation systems (ITS) are gradually becoming a reality in many cities and more developments are underway with the objective of improving road traffic efficiency and safety (Crainic et al, 2004;Khademi et al, 2010) and decreasing the level of uncertainty (Zerguini et al, 2011). ITS includes a wide range of cutting-edge technologies which are applied on the driver-vehicle-highway system in order to improve throughput, safety, and efficiency using advanced sensors, computers, and communication devices (Barfield and Dingus, 2014).…”

Travel Time Reliability Measures Accommodating Scheduling Preferences of Travelers

“…In contrast, the second approach considers the costs associated with schedule delay early and schedule delay late to model travel time reliability. Several previous studies reported that schedule delay early and schedule delay late are crucial factors influencing travelers' decisions such as choice of departure time and choice of route (16)(17)(18)(19).…”