Determining explanatory factors for road demand in interurban toll roadsan asserted approach

Resumen

Improving the knowledge of road demand behaviour and estimating more accurate traffic forecasts constitute critical aspects for the evaluation of transport policies and for the assessment of future investment needs. For this reason, stakeholders involved in road infrastructure management (governments, private operators, etc.) find it essential to identify the key parameters influencing road demand, as well as to quantify the relationships between traffic and certain explanatory variables. This is especially critical in the case of toll concession roads, since road infrastructure is directly financed through users´ contributions. At this point, since tolls have become a mechanism increasingly adopted to fund road projects worldwide, exploring users´ perceptions and willingness-to-pay towards toll facilities is playing a growing role in transport policy initiatives and road infrastructure viability. The literature in the field of toll road infrastructure is scarce, particularly in the interurban context. Previous research have mainly focused on urban areas, while limited contributions have been made up to date to better understand mobility and users´ behaviour in interurban roads, especially tolled ones. Moreover, the existing literature on interurban toll roads has left some issues to be investigated, mainly the identification of the socioeconomic variables better explaining the evolution of road demand over time. In this respect, GDP has usually been the only macroeconomic variable considered to analyse and forecast light and heavy vehicle demand, but this choice has been generally based on no further reason than the usual practice. Based on the above considerations, the objective of this thesis is about providing knowledge for explaining road traffic demand over time as well as users´ perceptions and willingness-to-pay in interurban roads, taking Spain as case study. The research involves analysis at both the macro and the micro level to provide insight regarding road use behavior in interurban roads, particularly tolled ones. Particularly, a macro analysis is developed aimed at identifying those variables explaining road demand evolution over time in interurban toll roads. Based on a panel data methodology, this analysis is applied at the national level, for both light and heavy vehicle demand. Likewise, a micro analysis is conducted aimed at identifying the explanatory variables determining users´ perceptions and willingness-to-pay in interurban toll roads, as well as exploring the relationship observed between these two concepts. The thesis yielded some interesting conclusions for both policymakers and practitioners in the area of road demand management.