Simulation-Based Heuristic Approach for Dynamic Marginal Cost Pricing

This work offers a simulation-based heuristic for dynamic marginal cost pricing (MCP) that is a direct extension of static MCP. The heuristic approximates the time-dependent marginal costs, assuming that a vehicle entering a tolled link imposes marginal costs only on all following vehicles using this same link. As such, a link’s marginal cost is dynamically determined from the gradient of a quadratic fit to its travel time function. The proposed approximation is incorporated into the inner approximation dynamic user equilibrium (IADUE) algorithm to evaluate the results of dynamic MCP, which are then compared to static assignment results with MCP from previous study. The modified IADUE algorithm is implemented in the dynamic traffic assignment (DTA) module of the Visual Interactive System for Transport Algorithm (VISTA), which propagates traffic according to Daganzo’s cell transmission model. In addition, a new algorithm is proposed, to smooth the static travel demands across times of day when a dynamic demand distribution is unavailable. The status quo and dynamic MCP-on-freeways scenarios are simulated (and then compared) using the original and modified IADUE algorithms, respectively, on Dallas-Fort Worth 35,732-link network. Due to computational requirements for such large-scale DTA application, the dynamic MCP scenario is simulated without feedback, and only route choices are permitted to vary. When prices are imposed, some minor system benefits are observed, including a delay in the onset of congestion. Dynamic prices vary substantially over the analysis period, reflecting changes in congestion. Reasons for any inconsistencies between dynamic and static results are discussed, along with important enhancements to future implementation.

Language

  • English

Media Info

  • Media Type: DVD
  • Features: Figures; References; Tables;
  • Pagination: 26p
  • Monograph Title: TRB 87th Annual Meeting Compendium of Papers DVD

Subject/Index Terms

Filing Info

  • Accession Number: 01091914
  • Record Type: Publication
  • Report/Paper Numbers: 08-0438
  • Files: TRIS, TRB
  • Created Date: Jan 29 2008 2:47PM