Identification of some sources of heterogeneity in value of travel time of Tehran LEZ users

Document Type : Research Article


1 Transportation Planning Department, Faculty of Civil & Environmental Engineering, Tarbiat Modares University

2 Transportation Planning, Institute for Management and Planning Studies, Tehran, Iran.


Value of travel time (VOTT) plays a key role in the choices of travelers. Empirical studies have shown significant differences in VOTT estimates, which researchers attribute that to several factors, including demographic, alternatives, trip, and regional economic characteristics. One of the policies reducing use of private car is congestion pricing of the low emission zone (LEZ). This study aims to estimate VOTT and analyze its heterogeneity among users of Tehran LEZ. We use stated preference (SP) data to calibrate mixed logit models, based on which, travelers' value of time is evaluated. The mean value of travel time is calculated 5788 Rials per hour. Results of mixed logit model indicate cost coefficient with triangle distribution (mean -0.00036) and travel time coefficient with normal distribution (mean -0.20838). To investigate the source of VOTT heterogeneity, random coefficients analysis is used for the interaction between coefficients of time and cost and other variables revealing that only cost as a factor with three variables: number of entrance to LEZ, number of household cars, and high education are significant.


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