Multiple Discrete Extreme Value Model Research Articles

Exploring Multiple\u2010discreteness in Freight Transport. A Multiple Discrete Extreme Value Model Application for Grain Consolidators in Argentina

There are some examples where freight choices may be of a multiple discrete nature, especially the ones at more tactical levels of planning. Nevertheless, this has not been investigated in the literature, although several discrete-continuous models for mode/vehicle type and shipment size choice have been developed in freight transport. In this work, we propose that the decision of port and mode of the grain consolidators in Argentina is of a discrete-continuous nature, where they can choose more than one alternative and how much of their production to send by each mode. The Multiple Discrete Extreme Value Model (MDCEV) framework was applied to a stated preference data set with a response variable that allowed this multiple-discreteness. To our knowledge, this is the only application of the MDCEV in regional freight context. Free alongside ship price, freight transport cost, lead-time and travel time were included in the utility function and observed and random heterogeneity was captured by the interaction with the consolidator’s characteristics and random coefficients. In addition, different discrete choice models were used to compare the forecasting performance, willingness to pay measures and structure of the utility function against.

A escolha de não ser discreto: discutindo a utilização de modelos discretos contínuos no transporte de carga

O transporte de carga tem utilizado os modelos herdados do transporte de passageiros e com eles todos seus pressupostos tradicionais. Mas são todos eles válidos? O presente artigo visa discutir sobre um dos pressupostos menos contestados neste processo de modelagem: o da exclusividade mútua das alternativas no contexto do transporte de carga. Para isso, este artigo apresenta uma aplicação de Multiple Discrete Extreme Value Model (MDCEV) para a escolha de modo e porto para os consolidadores de grãos na Argentina. O modelo é desenvolvido a partir de uma pesquisa de Preferência Declarada que permitia a escolha de mais de uma alternativa simultaneamente. A escolha é descrita pelo Tempo de Viagem, Tempo de Espera do Serviço, Preço de venda no porto e Custo do Frete. O MDCEV permitiu obter informação sobre o efeito da saciedade das diferentes alternativas. De esta maneira, o MDCEV pode ser uma ferramenta valiosa para a modelagem de escolhas táticas e estratégicas.

Application of MDCEV to infrastructure planning in regional freight transport

• Application of MDCEV model to regional freight. • Destination port and transport mode choice model. • Use of consignment bills (RP) and SP data for modelling. • Rail infrastructure improvement evaluation. • Non-deterministic willingness to pay and cost benefit analysis. The main objective of the paper is to develop a model capable of evaluating the societal impact of rail infrastructure investment in Argentina, using a Multiple Discrete Extreme Value Model (MDCEV) estimated on Stated and Revealed preference data. The decision modelled is the mode and port choice at a planning level, where multiple alternatives can be chosen simultaneously. The relevant variables were the Free Alongside Ship (FAS) price, freight transport cost , travel time and lead time , including non-observed heterogeneity in the modelling. As a consequence, the willingness to pay measures that are used for the cost benefit analysis become non-deterministic. To include this effect simulated WTP measurements were included and compared to a deterministic and risk based approach. Two projects were tested and both showed that the deterministic approach gives higher Benefit/Cost ratio. This paper raises the concern that if non-observed heterogeneity is not considered in project evaluation it may provide misleading results and potentially lead to wrong investment priorities for the public sector.