What are we counting? Getting inputs correct to improve modelling outcomes [traffic flow]

A great traffic engineer and modeller once said that every traffic model that is built is wrong because the flow is counted, not the demand. Because the traffic flow is counted, base case models should never be over-saturated. Traffic count balancing required for models such as simulation can amplify this problem. The result of this can be a model that does not reflect observed traffic conditions. If the base case model is not correct, the validity of the forecast models can also be called into question. But how serious is this issue and what are the implications of this for project development and assessment? This paper will provide practical examples of how counting the flow can produce unrealistic modelling outcomes from a range of modelling packages. It will outline the effects this may have on assessing projects and provide some alternative methods to improve models through better data collection.

• Record URL:
  http://www.atrf.info/papers/index.aspx
• Authors:
  • Zito, C
  • Tat, L
  • Tamhane, A
• Conference:
  • Australasian Transport Research Forum (ATRF), 34th, 2011, Adelaide, South Australia, Australia
• Publication Date: 2011-9

Language

• English

Media Info

• Pagination: 13p
• Serial:
  • Volume: 34
  • Issue Number: 0215

Subject/Index Terms

• TRT Terms: Evaluation; Mathematical models; Traffic counts; Traffic flow; Travel demand
• ATRI Terms: Evaluation; Modelling; Traffic count; Traffic flow; Travel demand
• ITRD Terms: 285: Demand (econ)
• Subject Areas: Operations and Traffic Management; I71: Traffic Theory;

Filing Info

• Accession Number: 01369501
• Record Type: Publication
• Source Agency: ARRB
• Files: ITRD, ATRI
• Created Date: May 3 2012 10:45AM