High Speed Rail Demand Forecasting: Italian Case Study

This paper will discuss how recent High Speed Rail (HSR) investments in Italy include new services for the following city pairs: Rome-Naples, 204 Km, in 2005; Torino-Novara, 148 Km, in 2006; Milano-Bologna, 214 km, in 2008; and, in approximately one year, the backbone of the Italian HSR network that connects Milan to Naples (i.e. the North-South corridor) and Torino-Milano (i.e. the North-west corridor) will be complete. Moreover, starting in 2012, a new private HSR operator (i.e. “Nuovo Trasporto Viaggiatori” – NTV) will enter the HSR market, competing with the national railways operator (i.e. Trenitalia). The above structural changes in the Italian national transportation market, together with the ongoing economic crisis with no antecedents in the globalization era, create the conditions for a unique case study to investigate the behavior of long-distance passengers. The paper presents a national passenger demand model system with application to different macroeconomic, transport supply, and HSR service and marketing scenarios. The forecasting model system consists of three integrated sub-models: the “demand growth” model that projects the base year origin and destination (OD) matrices to future years, according to assumed macroeconomics trends; the “mode/service choice” model that estimates the market share of different inter-urban transportation modes, including alternative rail services (such as Intercity, Eurostar, High Speed, by 1st and 2nd class); and the “induced demand” model which estimates the additional HSR demand due to the improvement of HSR level of services (i.e. new services, travel time reductions, etc.). The demand growth model expresses the total demand as a function of macro-economic variables (e.g. gross domestic product [GDP] growth, fuel price changes, etc.). The model was calibrated using time series (1970-2007) data of Italian highway traffic. It is used to derive elasticities of demand with respect to GDP growth for periods of increasing economy and for periods of recession. The model is validated by comparing predicted and actual changes in traffic. The model prediction is also compared to the expected reduction during the recession period of 2008-2010, and is then applied to extrapolate the OD matrices from to the base year (2011) to the future. The mode/service choice model is a set of nested logit models with a nesting structure to capture higher degrees of substitutions among specific subsets of modal alternatives, particularly the HSR alternatives provided on the same route by different operators (NTV vs. Trenitalia). These discrete choice models were estimated using an revealed preference-stated preference (RP-SP) survey carried out during April-May 2009. The induced demand model is based on a relationship between existing HSR demand (dependent variable) to existing HSR travel times and costs. The covariates include socioeconomic variables related to population and employment in the zones connected by the HSR services. This model was calibrated by mean of a before and after study carried on travel in the Napoli-Roma corridor, when the new HSR services was introduced. The model is being applied to predict the impacts on national passenger volumes, of the new HSR services and operators as of 2012. Different scenarios have been tested under different macroeconomic assumptions and marketing strategies of the main passenger transportation competitors on the long distance routes. The results of these applications will be presented and discussed in the paper.