摘要: |
The 1990 Census Transportation Planning Package (CTPP) for the Delaware Valley Region is analyzed, with special emphasis on journey-to-work trips, employment, mode of transportation to work, travel time, vehicle ownership, employed persons, and other socioeconomic data essential to transportation planning and travel forecasting. A review of the CTPP computer tapes and data showed some programming, sampling, and bias problems, which were resolved before the data were used as a base for trend analysis, traffic simulation, highway and transit project studies, strategic planning, and economic development. The CTPP information should be adjusted before it is used for transportation planning. The errors in the 1990 CTPP data are generally small, but the package shows no improvement over the 1980 data. Most of the 1990 CTPP problems can be avoided in the future if the recommendations made in this paper are considered in the 2000 census. |