The National Academies

NCHRP 08-30 [Completed]

Characteristics and Changes in Freight Transportation Demand

  Project Data
Funds: $550,000
Research Agency: Cambridge Systematics, Inc.
Principal Investigator: Herbert Weinblatt and Harry Cohen
Effective Date: 12/12/1992
Completion Date: 2/29/1996

Many changes are taking place in the United States and abroad that profoundly affect freight transportation demand. These include changes in demographics, energy availability, cost, production, industry and logistics practices, and U.S. roles in the global economy. Such changes are affecting the type of freight moved, its density and packaging, its origin-destination patterns, and its requirements for delivery. The need has been recognized for comprehensive freight policies at both the state and national levels, but research is needed first to address critical issues. Further study is necessary to (1) better understand the characteristics of freight transportation demand, (2) assess trends in the characteristics of freight, (3) identify the key factors that promote changes in domestic freight transportation demand (including the domestic component of international movements), and (4) determine the interrelationships between freight transportation demand and supply. This research is needed to support the development of a process for forecasting future freight transportation demand. It would also provide critically needed background information for the analyses of (1) modal competition and coordination, (2) the influences of institutions, investments, and policies, and (3) the impacts on transportation infrastructure, safety, operations, and financing.

The objectives of this research are to examine the changing character and composition of U.S. freight transportation demand across all modes and to develop a process to effectively forecast future demand. This will involve macro-level analyses over time of the characteristics of freight transportation demand and its changes, the key economic, technological, political, and social factors that contribute to those changes, and the interaction effects between freight transportation demand and system supply.

To accomplish this objective, a three-phased effort is envisioned. The first phase will characterize freight transportation demand in measurable and relevant terms, summarize current understanding of the key factors that affect, or are likely to affect, freight transportation demand, and determine the interrelationships between the key factors and freight demand characteristics. The second phase will conceptualize a process for forecasting future freight transportation demand and will assess the feasibility of this process, considering the availability of information, the nature of changing practices, the ability to monitor future conditions, and the complexity of the interactions between actors. The last phase will focus on the development, enhancement, and documentation of the process including the formulation of prototype models.

Phase I: Summarize Freight Transportation Demand Information and Trends. (1) Identify the most critical questions about freight transportation demand at the federal, state, and local levels through (a) agency interviews, (b) a review of modal policies and legislative initiatives, and (c) a review of past freight studies. Also, identify the methods that have been used to address these questions and assess the extent to which they have been integrated into transportation system planning. (2) Establish an advisory group of at least 8 recognized experts in freight transportation logistics, operations, and modeling from the public and private sectors, as well as academia, to provide insights into the impacts of changing manufacturing, shipping, packaging, carrier operation, and marketing practices. The advisory group will be expected to provide feedback on the various working papers and to participate in the planned workshop. (3) Identify the key characteristics of freight transportation demand (for individual modes and across modes) and specific measures for each. Examples of characteristics are commodity types, shipment size and density, shipment distance and frequency, delivery requirements, and origin-destination patterns. Assess the viability of existing databases, anticipated new data and classification schemes to support the measures of freight transportation demand characteristics. (4) Identify the key economic, social, political, technological, environmental, or other factors that influence the characteristics identified in Task 3. Identify specific measures for each key factor and assess the viability of existing and anticipated databases and classification schemes to support future freight transportation demand forecasting. Critical current and emerging factors should be highlighted and their consequences cited. Examples of current key factors include the emergence of a global economy and new regional blocks, changing industry production practices, changes in distribution techniques and technologies (e.g., just-in-time delivery, electronic data interchange), and regulations. (5) Identify trends and relationships between freight transportation demand characteristics identified in Task 3 and the key influencing factors identified in Task 4 and consider the influences of transportation supply on the trends and relationships. The qualitative and quantitative trends or relationships identified are expected to serve as a basis for forecasting freight transportation demand and to support other research. The findings of this task should be succinctly summarized in an interim report that will be submitted to the NCHRP panel and advisory group for review.

Phase II: Conceptualize Freight Transportation Demand Forecasting Process. (6) Outline a process for forecasting freight transportation demand, which will include procedures to identify emerging influences and scenarios, relate the influences of transportation system supply, and apply econometric, network simulation, or other appropriate models to assess the impact of future conditions on freight transportation demand. Emphasis should be focused on developing an effective, state-of-the-art process considering freight characteristics, the key influencing factors, the relationships defined in Task 5, and the types of questions that need to be answered. The applicability and adaptability of past approaches and models for forecasting freight transportation demand should be determined. (7) As part of the freight transportation demand forecasting process conceptualized in Task 6, establish systematic procedures for analyzing how emerging factors and other external changes can shape the characteristics of freight transportation demand. These future mapping procedures should be oriented for use by decision makers to address the types of questions identified in Task 1. The future mapping procedures should identify the critical pieces of information required and the potential range of outcomes for freight transportation demand analyses. (8) Describe the application of the forecasting process to address typical freight transportation questions in the context of at least two case study situations. One situation should focus on a national-level application and the second on a state- or regional-level application. The contractor should assess the availability of data, the reliability of the procedures, the uncertainty associated with forecasts, the changing importance of factors, the applicability to different agencies, and the range of issues that can be addressed. (9) The contractor will prepare a second interim report that will fully describe the conceptual freight transportation demand forecasting process, the future mapping procedures, the case study applications, and the feasibility assessment. The contractor will organize a workshop forecasting freight transportation demand to provide an opportunity for discussion of the findings of Phase I and the forecasting process conceptualized in Phase II. During the workshop, participants will validate the characterization of past and emerging freight transportation demand trends and relationships and thoroughly critique the conceptualized freight transportation demand forecasting process. The workshop should be structured to include a step-by-step demonstration of the process for the case study situations. The workshop participants will be expected to evaluate the feasibility of the process in terms of data availability, process integrity, forecast sensitivity, and other aspects. The contractor will be expected to prepare a comprehensive summary of the deliberations and conclusions of the workshop and to incorporate these as appropriate into subsequent project efforts and reports.

Phase III: Refine, Develop, and Document Forecasting Process. (10) If the workshop participants conclude that it is feasible to forecast future freight transportation demand, develop prototype models for use in the forecasting process conceptualized in Phase II. The prototype models should be developed considering the availability of data, the trends and relationships identified in Task 5, and the functionality and adaptability of past forecasting approaches and models. Prototype models should be developed for broad applicability in addressing the range of questions faced by federal, state, and local agencies. Test the prototype models against the case study scenarios previously developed. (11) Develop an easy-to-use guidebook for the application of the process and models. The guidebook should identify the key information needed for scenario assessments, describe methods to collect this information, outline the steps in the forecasting process, and apply the prototype models. (12) Recommend an implementation strategy appropriate for federal, state, and local agencies to adopt the freight transportation demand forecasting process. The strategy should reflect the requirements for Intermodal Management Systems in the Intermodal Surface Transportation Efficiency Act and other applicable policies. (13) Prepare a final report that includes recommended work plans with cost estimates for the second research stage to fully develop the freight transportation demand forecasting process.

Status: The project has been completed. The guidebook has been published as NCHRP Report 388.

To create a link to this page, use this URL: http://apps.trb.org/cmsfeed/TRBNetProjectDisplay.asp?ProjectID=896