Uncertainty in Integrated Land Use-transport Models
Author | : Anant Pradhan |
Publisher | : |
Total Pages | : 42 |
Release | : 2002 |
ISBN-10 | : NWU:35556034503706 |
ISBN-13 | : |
Rating | : 4/5 (06 Downloads) |
Download or read book Uncertainty in Integrated Land Use-transport Models written by Anant Pradhan and published by . This book was released on 2002 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report examines the impact of uncertainty in the land use component of a partially integrated land use-transportation modeling system called UrbanSim. Outputs from the land use model (LUM) act as inputs for a traditional 4-step travel demand model (TDM), and travel times from the traffic-assignment stage of the TDM are fed forward into the subsequent year's LUM. This work examines the propagation of uncertainty across model stages as well as at each model stage over time. A factorized design approach is used to model uncertainty in demographic inputs to the LUM, as well as uncertainty in various model parameters. Results suggest that while several model inputs may affect model outputs in the short run, only those inputs having a cumulative effect are likely to have a significant impact on outputs in the long run. Results also suggest that uncertainty in model outputs may increase for the first few years for which the model is run, as modified inputs send shocks through the urban system. However, the uncertainty level seems to come down in later years, as jobs, households, and developers respond to changed input conditions.