Predicting Intermodal Transport Changes Through a Flow Game Framework
Athena Roumboutsos, University Of The Aegean
An alternative conceptual model to predict the potential of intermodal freight transport is offered based on flow game theory. Emphasis is placed on predicting the potential of establishing modal and operator alliances. The model is compared to case studies reported in literature and shown to be able to interpret and predict operator strategies and best practices. Public decision makers when devising policy measures may use the model as a tool. The model may also be used to predict the impact of the economic downturn on supply chain alliances.
Keywords: Intermodal transport, Game theory, Transport policy, Market Structure, Strategies
The promotion of intermodality constitutes the corner stone in achieving modal shift from road to other modes of transport and requires the organisation of integrated door-to-door chains, using rail or sea transport for a significant part of the total chain, limiting road transport to the pre-haul and end-haul operations. Efforts to understand market development drivers have been principally focused on: (1) considering the economics of intermodal freight transport (2) transport chain choice based on behavioural attributes, (3) policy strategies and measures to improve the supply side of intermodal freight transport.
However, standard intermodal services are associated with the involvement of a substantial number of market-actors with conflicting strategies and interests, which add to the complexity of the transaction. The challenge remains the reconciliation of supply-oriented and strategic planning of infrastructures with demand-oriented provision of transport and logistics services in a competitive environment. Understanding the market on a macro (transport sector) level and micro (operator) level is important in projecting future trends and assessing the impact policy measures and other external effects (eg economic crisis) may have.
The present work aims at providing insight on the drivers of market structure within intermodal freight transport. The problem is addressed through a conceptual flow game. The application of game theory to transport problems is not novel and researchers have recognised the existence of strong connections between traffic assignment principles and game theory. Network games trying to predict user equilibrium and/or system optimum have been addressed through the Nash equilibrium as cooperative and non-cooperative games. The present model bears two distinct differences to previous efforts: (a) it seeks to predict cooperation and competitive behaviour through the identification of coalitions formed in order to address the basic question “which alliances-coalitions will form” and (b) remains at a generalised (conceptual) level in order to provide policy guidelines and predict player strategies. The model, while investigating the supply side on both a macro (transport modal) and micro (operator) level and its feasibility, takes into account, indirectly, the aggregate user utility on the respective levels and, therefore, considers both user equilibrium and system optimum. This bears a number of advantages the most prominent being the fact that the model does not seek to identify equilibrium of supply and demand, or the rationalization of user and supplier choices which are system specific but highlights the mechanisms of alliances on a modal level (i.e. mechanisms leading to intermodal transport) and on an operator level (i.e. identification of market strategies).
The objective is to overcome the limitations of specific model development and/or generalisation of conclusions drawn from case studies and provide a macro understanding of potential evolutions, their underlining causes and potential effects. Consequently, the model may be used as a decision tool for policy makers aiming to minimise the externalities of transport activities and players in the logistic chain aiming to secure pay-offs under varying macro-economic conditions.
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Association for European Transport