| EPSRC Reference: |
GR/L79540/01 |
| Title: |
THE DEVELOPMENT OF TECHNIQUES FOR THE ESTIMATION OF CONFIDENCE INTERVALS FOR TRAFFIC ASSIGNMENT MODELS |
| Principal Investigator: |
Watling, Professor D |
| Other Investigators: |
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| Project Partners: |
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| Department: |
Institute for Transport Studies |
| Organisation: |
University of Leeds |
| Scheme: |
Standard Research (Pre-FEC) |
| Starts: |
01 October 1998 |
Ends: |
30 September 2001 |
Value (£): |
115,762
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| EPSRC Research Topic Classifications: |
| Transport Ops & Management |
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| No relevance to Underpinning Sectors |
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Summary on Grant Application Form |
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The calibration of road traffic network assignment models is a notoriously difficult task, the input data (such as travel patterns) being prone to large estimation/sampling errors and inherently variable. However, hardly any effort has been made at a formal statistical treatment of the prediction errors. The proposal addresses this issue by developing new methodologies for: (i) the estimation of sampling errors, and thence confidence intervals, in the output measures (mean flows, travel times), corresponding to given sampling errors in the input data (mean OD matrix, capacities);(ii) the extension of existing equilibrum models to incorporate underlying day-to-day variability in both input and output variables, providing predictions of - for example - underlying link flow variances.The first task will be achieved by deriving and implementing new results on the sensitivity of the stochastic equilibrum assignment model to parameter perturbations, and by making use of recent advances in the algorithms available to estimate such equilibra. The second task will be achieved by extending a model recently proposed by the present author, which itself is an extension of the stochastic equilibrum model to a doubly stochastic approach that incorporates both flow and travel time variability in the equilibrum process.
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Key Findings |
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This information can now be found on Gateway to Research (GtR) http://gtr.rcuk.ac.uk
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Potential use in non-academic contexts |
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This information can now be found on Gateway to Research (GtR) http://gtr.rcuk.ac.uk
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Impacts |
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| Description |
This information can now be found on Gateway to Research (GtR) http://gtr.rcuk.ac.uk |
| Summary |
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| Date Materialised |
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Sectors submitted by the Researcher |
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This information can now be found on Gateway to Research (GtR) http://gtr.rcuk.ac.uk
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| Project URL: |
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| Further Information: |
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| Organisation Website: |
http://www.leeds.ac.uk |