METHODOLOGY FOR ESTIMATING DETAILED INTERAREA COMMODITY FREIGHT FLOWS FROM CENSUS OF TRANSPORTATION DATA, (1977)

This data set provides data on flow of specific commodities between states, as well as major production and market areas. Unfortunately, the completeness of this data is limited by the statutory requirement that the Census Bureau not release data which might reveal information about the operations of individual firms. As a result of this non-disclosure requirement, data are withheld on shipments of a particular commodity group whenever there were only A few firms sampled which made shipments in that commodity group. Since there is no way to determine the volume of flow for each of these unreported commodity groups directly from the census data, the data are inadequate for freight transportation planning studies conducted at a detailed commodity level. This report presents an algorithm which has been developed for estimating the volume of each unreported area to area flows among specific commodity groups in proportion to the flows of these commodity groups in nationally aggregated data. The algorithm has been programmed. A listing of the program and necessary documentation is included as an appendix. Prepared for the U.S. Department of Transportation, Office of University Research, Analysis of Freight Markets. The most widely used data available on U.S. interarea commodity freight flows comes from the public use tapes of the Census of Transportation Commodity Transportation Survey.

  • Corporate Authors:

    Massachusetts Institute of Technology

    Center for Transportation Studies, Room 1121
    Cambridge, MA  USA  02139
  • Publication Date: 1977

Subject/Index Terms

Filing Info

  • Accession Number: 00321049
  • Record Type: Publication
  • Source Agency: Transportation Systems Center
  • Files: TSR
  • Created Date: Oct 30 1982 12:00AM