Aggregated modeling of urban taxi services

Various models have been developed for calculating the variables that characterize the taxi services in urban regions and defining the principal policy measures such as fleet size, fares or available operational modes. This paper presents an extensive review of the presented formulations for the modeling of taxi services in urban areas. The variables of the problem are identified and analyzed, presenting the different formulations proposed in the literature for each one of the three operational modes (hailing, stand and dispatching). The paper also presents an aggregated mathematical model for the estimation of the key performance indicators of taxi markets in urban areas taking into account demand elasticity. These key parameters are basically the demand and supply for taxi services, the waiting time of taxi users and the cost of the involved actors, i. e. the customers and the drivers. A generalized cost function is proposed and applied to the dispatching taxi services market, obtaining results in terms of demand, system unitary costs, waiting time and drivers’ benefit for different combinations of supply and fares. It is concluded that demand is more sensitive to waiting time than to cost for high waiting times, but when the waiting time is low, the cost is the most significant factor of the demand