E-C158 Cover1 - Center for Transportation Analysis - Oak Ridge ...

Scope, Classification, and Geography 17
― Should adding (oversampling) additional metropolitan areas to the CFS sample be
considered? How well has adding freight gateways that are metropolitan areas
worked out in the 2007 CFS?
― What other local areas can be considered for the 2012 CFS instead of MSAs? Is
moving to Census Statistical Areas (CSAs) a possibility, and what are the drawbacks?
Gregory Harris discussed the use of FAF in Alabama where FAF values were
disaggregated to the local level using local surveys and truck conversions. The city of Mobile
helped in developing trip purposes, O-D pairs, and through-traffic volumes and the project team
obtained information from the port on goods that stay locally and goods that leave the state. The
team then filled in missing products in the FAF, such as forestry products, using other Census
products and BEA data to obtain variables such as personal income. Of these, waste and scrap
and recyclables were probably the most problematic to account for in trip estimation. Truck
counts from Alabama DOT were used to validate trip generation results.
As a long-time partner in providing critical factors for the CFS and FAF, Frank
Southworth provided unique insight into several aspects. Within the water transportation
community, waterway trips have been redefined as intermodal trips, which more closely
represent reality. With this shift, coordinating data definitions between sources such as the CFS
and the U.S. Army Corps of Engineers would improve the ability of users to work across
multiple data sources. Particularly for metropolitan planning organizations (MPOs), O-D detail is
important to route traffic. Inclusion of gateways in the 2007 CFS provided some improvement in
this area. One possible idea would be to take out geography detail to provide more detail on other
dimensions such as three- or four-digit level SCTGs.
Comments and questions from workshop attendees included the following:
• Shippers do not necessarily have information about carriers.
• As a result, more than one survey may be necessary to obtain desired information and
not rely on the CFS to cover all needs.
Comments and questions related to SCTG were as follows:
• A desire was expressed for a need for a concordance between NAICS and SCTG to
anchor and guarantee consistency.
• Do we need to produce a five-digit manual? SCTG has 499 five-digit codes and 41
two-digit codes. Commodity detail is only useful for modeling purposes if it ties to economic
activity. A problem may occur where a commodity code spans two industries. If possible, the
ability to maintain consistency between industry and commodity code was considered important.
• SCTG classification needs to do two things:
― Provide attributes to allow linkages to economic data and
― Separate commodities by common transportation characteristics.
• Oversampled hazmat flows in the last survey is an example of improvement in scope.
Could air freight be oversampled to accomplish a similar benefit?
• Census is considering moving from MSAs to CSAs to standardize geographies so
users can pull data from lots of different databases and be on the same basis. This will probably
result in redefining some of the large MSAs in CFS to CSAs. If this happens many of the current