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Conflation Methodologies to Incorporate Consumer Travel Data into State HPMS Data Sets
TRB 92nd Annual Meeting Compendium of Papers (2013)
  • Eric R. Green, University of Kentucky
  • John B. Ripy, University of Kentucky
  • Mei Chen, University of Kentucky
  • Xu Zhang, University of Kentucky
The objectives of this study were to evaluate the feasibility of using private sector speed data to generate performance measures in Kentucky. These measures can be used to annually facilitate congestion management and travel model improvements by creating a mechanism to integrate commercially available speed data into Kentucky’s existing transportation network. Also, due to the large number of records in these databases, this research identified methods to effectively display data to state and metropolitan planning organization (MPO) employees to maximize the benefit of its use. This research helped to coordinate the purchase of two datasets: 2010 analytical traffic pattern data on the Traffic Message Channel (TMC) network in Kentucky and a more complete 2011 link-based network which included a broader coverage. Both data sets included average speeds, probe counts, and the standard deviation for each time interval for various time periods. In order for these datasets to be useful to state and local agencies, they were conflated with Kentucky’s existing highway network. Both of the datasets were linked to networks that differ from the state’s Highway Performance Monitoring System (HPMS) network. There is a need to link the purchased data to the state’s network as it contains attributes critical in developing performance measures. The usefulness of the private sector speed data relied greatly on the success of the conflation process with the state’s HPMS data. In order to derive performance measures from the data, several state-owned attributes were needed (such as traffic volumes and highway type). It was found that the TMC network provided more reliable descriptive statistics as compared to the link-based network which used free-flow speeds in records with no probe data. Free-flow speeds are useful as a secondary estimate for travel times for navigation, but not for performance measures. Conversely, the coverage of the link-based network was significantly more prominent than that of the TMC-network.
  • Conflation Methodologies,
  • Consumer Travel Data,
  • State HPMS Data Sets
Publication Date
Citation Information
Eric R. Green, John B. Ripy, Mei Chen and Xu Zhang. "Conflation Methodologies to Incorporate Consumer Travel Data into State HPMS Data Sets" TRB 92nd Annual Meeting Compendium of Papers (2013)
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