National Academies Press: OpenBook

Innovations in Freight Demand Modeling and Data Improvement (2014)

Chapter:Discrete Model of Freight Mode and Shipment Size Choice

« Previous: Logistics in Freight Modeling A Report from the Delft Group
Page 44
Suggested Citation:"Discrete Model of Freight Mode and Shipment Size Choice." National Academies of Sciences, Engineering, and Medicine. 2014. Innovations in Freight Demand Modeling and Data Improvement. Washington, DC: The National Academies Press. doi: 10.17226/22336.
×
Page44
Page 45
Suggested Citation:"Discrete Model of Freight Mode and Shipment Size Choice." National Academies of Sciences, Engineering, and Medicine. 2014. Innovations in Freight Demand Modeling and Data Improvement. Washington, DC: The National Academies Press. doi: 10.17226/22336.
×
Page45

Below is the uncorrected machine-read text of this chapter, intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text of each book. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Discrete Model of Freight Mode and Shipment Size Choice Megersa Abate and Inge Verth Swedish National Road and Transport Research Institute Gerard de Jong University of Leeds Presentation Notes: Presented by Megersa Abate, Swedish National Road and Transport Research Institute. The model is based on a deterministic cost model, with the minimization of total annual logistics costs. The current model lacks two main elements: it does not account for other determinants of shipment size and chain choices and it lacks a stochastic component. The data source was the national commodity data flow of about 2.8 million shipments. This model includes information for supply chain, weight, and infrastructure variables. Initial results show a low elasticity for transport costs for most modes. Abstract The main feature of the current Swedish national freight model system (SAMGODS model) is incorporation of a logistic component in the traditional freight demand modeling. The logistics module of the SAMGODS model estimates frequency/shipment size choice and transport chain choice (transport chain and mode choices and use of transshipment). Logistical decisions of firms are incorporated in the modeling process based on the shipment size optimization theory. According to this theory, firms are assumed to minimize total logistics costs by trading off inventory holding costs and transport costs. Judged by international standards in freight transport modeling, the SAMGODS model is relatively modern. Its logistic module, however, lacks two main elements. First, it does not account for main determinants of shipment size and transport chain choices other than cost, that is, decisions are solely based on cost consideration. Second, the model is deterministic and lacks a stochastic component. In order to improve the prediction of the model, logistical decisions should be modeled taking into account these two elements. A full random utility logistic model which accounts for this was planned but has not yet been estimated on disaggregated data (de Jong and Ben-Akiva 2007). This project is a first step toward estimating a full random utility logistic model. The researchers will formulate a model of transport chain and shipment size choice using the 2004– 2005 Swedish Commodity Flow Survey. The main econometric work in this project involves modeling the interdependence between shipment size and transport chain choices using a joint (e.g., discrete-continuous) econometric model. Parameter estimates from this model will later be used for estimation of a full random utility logistic model. They will also be used to estimate transport time and cost elasticities to analyze policy outcomes. 44

Reference de Jong, G., and M. Ben-Akiva. A Micro-Simulation Model of Shipment Size and Transport Chain Choice. Transportation Research Part B, Vol. 41, Issue 9, 2007, pp. 950–965. 45

Next: Freight Models, Constrained Economic Models, and Natural Resource Data »
Innovations in Freight Demand Modeling and Data Improvement Get This Book
×
MyNAP members save 10% online.
Login or Register to save!
Download Free PDF

TRB’s second Strategic Highway Research Program (SHRP 2) Report: Innovations in Freight Demand Modeling and Data Improvement provides detail to the events of "The TRB Second Symposium on Innovations in Freight Demand Modeling and Data," which took place October 21-22, 2013. The symposium explored the progress of innovative freight modeling approaches as recommended by the Freight Demand Modeling and Data Improvement Strategic Plan.

  1. ×

    Welcome to OpenBook!

    You're looking at OpenBook, NAP.edu's online reading room since 1999. Based on feedback from you, our users, we've made some improvements that make it easier than ever to read thousands of publications on our website.

    Do you want to take a quick tour of the OpenBook's features?

    No Thanks Take a Tour »
  2. ×

    Show this book's table of contents, where you can jump to any chapter by name.

    « Back Next »
  3. ×

    ...or use these buttons to go back to the previous chapter or skip to the next one.

    « Back Next »
  4. ×

    Jump up to the previous page or down to the next one. Also, you can type in a page number and press Enter to go directly to that page in the book.

    « Back Next »
  5. ×

    To search the entire text of this book, type in your search term here and press Enter.

    « Back Next »
  6. ×

    Share a link to this book page on your preferred social network or via email.

    « Back Next »
  7. ×

    View our suggested citation for this chapter.

    « Back Next »
  8. ×

    Ready to take your reading offline? Click here to buy this book in print or download it as a free PDF, if available.

    « Back Next »
Stay Connected!