Published in 2003
It is well known that better freight forecasting models and data are needed, but the literature does not clearly indicate which components of the modeling methodology are most in need of improvement, which is a critical need in an era of limited research budgets. This effort sought to identify those components using a logistics-driven approach as a starting point. The research began by examining other states' responses to freight planning legislation. A survey was sent to 47 states to determine the types of freight planning and freight modeling that occur and to understand the current data available and data needs. Research was conducted to gather information on how the supply chain functions and how logistics decisions regarding supply chain management are made. Sample supply chains were created for a variety of commodities, and mode choice was related to the behavioral aspects of the supply chain's logistics system. Once the mode was determined, the route assignment could be determined based on the accessible freight infrastructure. It was found that not all elements of the freight modeling methodology are equally weak: indeed, trip attraction components for the production of raw materials and the dissemination of these materials from the manufacturing plant, whether to the consumer (in a traditional push system) or to a just-in-time distribution center (in the newer pull system) are adequately developed in practice. However, it is critical that future research address the following needs, listed in order of descending priority: (1) the mode choice component for delineating travel by air, truck, rail, water, or a combination thereof; (2) trip attraction equations for intermodal facilities that are used when manufacturing plants outsource key components rather than creating all components in-house, and (3) trip attraction equations for representing the flow of goods from distribution centers to the consumer.
Last updated: December 1, 2023