Positive feedback : exploring current approaches in iterative travel demand model implementation.

Details

• Alternative Title:
  Project title: Positive feedback : an examination of current approaches in iterative travel demand model implementation
• Creators:
  Reeder, Phillip ; Bhat, Chandra ; Lorenzini, Karen ; Hall, Kevin
• Corporate Creators:
  Texas Transportation Institute
• Corporate Contributors:
  Texas. Dept. of Transportation. Research and Technology Implementation Office ; United States. Federal Highway Administration
• Subject/TRT Terms:
  Transportation Policy Travel Demand Travel Demand Management Transportation Demand Management--Texas
• Publication/ Report Number:
  FHWA/TX-12/0-6632-1
• Resource Type:
  Tech Report
• Geographical Coverage:
  Texas
• Edition:
  Technical report; Sept. 2010-Aug. 2011.
• Corporate Publisher:
  Texas Transportation Institute
• Abstract:
  Currently, the models that TxDOT’s Transportation Planning and Programming Division (TPP) developed are
  
  traditional three-step models (i.e., trip generation, trip distribution, and traffic assignment) that are sequentially
  
  applied. A limitation of this sequential approach is an inconsistency between the travel time data used in the different
  
  stages of the process that may result in: (1) TDMs, which do not accurately reflect system-wide or corridor-level travel
  
  patterns, (2) travel times in alternative analyses that may not reflect accurate results, and (3) inaccurate results being
  
  used for the air quality determination process.
  
  To resolve these differences in the model sequence, researchers proposed an iterative feedback mechanism as
  
  an approach. This project researched current trends, practices, and tools in implementing a feedback approach for
  
  potential implementation in the TxDOT TDMs. In general, past research and practice underscores the importance of
  
  incorporating feedback loops in the travel demand process, especially in regions with moderate to high levels of traffic
  
  congestion during certain times of the day. Since the current TxDOT TDM model does not include any impedance or
  
  accessibility measures in the trip generation step, the best current approach is to feed back the output from the traffic
  
  assignment step to the trip distribution step. Overall, critical consideration should be given to the relative impact that
  
  implementing feedback might have on existing TxDOT-TPP practices. A feedback mechanism necessarily includes
  
  additional training and increases the calibration time associated with delivering base year travel models; and possibly
  
  could include additional data processing (and collection) related to time-of-day implementation.
  
  
• Format:
  PDF
• Funding:
  Project Number 0-6632
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha-512:fd477098402d128818228609f5c8d7a40b952406484363989ce6f31fabb8074f4018811bf6356a8c7301313aaab673e1296cfe12b8aa9d06868999e973401966
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/23940/dot_23940_DS1.pdf
• File Type:
  [PDF - 2.65 MB ]