Computational Issues in Increasing Spatial Precision of Traffic Assignments

Abstract

The practical feasibility is demonstrated of a traffic assignment method, dubbed area-spread assignment, that incorporates information on the spatial relationships between nodes, links, and zone boundaries. Tests of area-spread assignment were performed on networks from Fredericton, New Brunswick, and Racine, Wisconsin. To eliminate the effect of errors from other model steps in the tests, comparisons were made with a detailed network in Fredericton that contained all streets in the city and extremely small zones. The tests indicated that there is a substantial difference between area-spread assignment and a traditional assignment using centroid connectors. Area-spread assignment did a better job of replicating volumes on the detailed network, although computation times were much longer.

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References

Jan

, Horowitz

A. J.

, and Peng

Z.-R.

Using Global Positioning System Data to Understand Variations in Path Choice. In Transportation Research Record: Journal of the Transportation Research Board, No. 1725, TRB, National Research Council, Washington, D.C., 2000, pp. 37–44.

Daganzo

C. F.

An Equilibrium Algorithm for the Spatial Aggregation Problem of Traffic Assignment. Transportation Research, Vol. 14B, No. 3, 1980, pp. 221–228.

Horowitz

A. J.

Extensions of Stochastic Multipath Trip Assignment to Transit Networks. In Transportation Research Record 1108, TRB, National Research Council, Washington, D.C., 1987, pp. 66–72.

Goodchild

M. F.

, and Kemp

K. K.

, eds. NCGIA Core Curriculum in GIS. National Center for Geographic Information and Analysis, University of California, Santa Barbara, 1990 (available at www.ncgia.org).

Sosslau

A. B.

, Hassam

A. B.

, Carter

M. M.

, and Wickstrom

G. V.

NCHRP Report 187: Quick-Response Urban Travel Estimation Techniques and Transferable Parameters: A User’s Guide. TRB, National Research Council, Washington, D.C., 1978.

Martin

W. A.

, and McGuckin

N. A.

NCHRP Report 365: Travel Estimation Techniques for Urban Planning. TRB, National Research Council, Washington, D.C., 1998.

Powell

W. B.

, and Sheffi

The Convergence of Equilibrium Algorithms and Predetermined Step Sizes. Transportation Science, Vol. 16, 1982, pp. 45–55.

Meneguzzer

Review of Models Combining Traffic Assignment and Signal Control. Journal of Transportation Engineering, ASCE, March/April 1997, pp. 148–155.

Horowitz

A. J.

Intersection Delay in Regionwide Traffic Assignment: Implications of the 1994 Update of the Highway Capacity Manual. In Transportation Research Record 1572, TRB, National Research Council, Washington, D.C., 1997, pp. 1–8.

10.

Special Report 209: Highway Capacity Manual, 3rd ed. (1997 update), TRB, National Research Council, Washington, D.C., 1998.

11.

Horowitz

A. J.

Revised Queuing Model of Delay at All-Way Stop-Controlled Intersections. In Transportation Research Record 1398, TRB, National Research Council, Washington, D.C., 1993, pp. 49–53.