Two-direction methods for variable demand traffic assignment

A. Gordon, J. Springham, G. Skrobanski, M. Smith, A. Woods, Q. Lv, A Salis, Benjamin Heydecker (Editor)

Research output: Chapter in Book/Report/Conference proceedingConference contribution


The estimation of equilibria within variable demand transport models is a central requirement for the assessment of transport proposals. Currently, given a transport model, the process of finding equilibria invariably now involves following a single search direction within the model repeatedly; aiming to reduce a measure of disequilibirium to approximately zero. This paper introduces two-direction methods for finding traffic equilibria; in these methods two directions are followed alternately instead of just one repeatedly. For each two-direction method described it is shown that, away from equilibrium and under natural standard conditions, one of the two directions certainly reduces a natural measure of disequilibrium. The paper also gives a counterexample showing that under these same natural conditions the search direction utilized is an algorithm called algorithm 1 is not guaranteed to reduce the degree of disequilibrium.
Original languageEnglish
Title of host publicationFourth IMA International Conference on Mathematics in Transport
Number of pages25
ISBN (Print)9780080450926
Publication statusPublished - 2005
EventFourth IMA International Conference on Mathematics in Transport - London, United Kingdom
Duration: 7 Sep 20059 Sep 2005


ConferenceFourth IMA International Conference on Mathematics in Transport
CityLondon, United Kingdom

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