Spatial and temporal aggregation analysis for space-mean speed estimates using autoscope video detection data

Zhongyi Wu, Hing Keung William Lam, Mei Lam Tam

Research output: Chapter in book / Conference proceedingConference article published in proceeding or bookAcademic researchpeer-review


Space-mean speed is an important indicator of road network performance in traffic operations and management. To collect travel time and speed data, video detectors or loop detectors are usually deployed. However, most detectors, such as Autoscope Video Detection System, measure spot speed or time-mean speed directly but not the space-mean speed over a section of roadway. An approximation method, which is commonly used to estimate space-mean speeds, is based on the average speed of vehicles traveling on a given segment of roadway during a specified period of time. However, such segment of roadway and specified period of time (refer to spatial and temporal aggregations) have significant effects on the estimation of space-mean speed. This paper investigates the effects of spatial and temporal aggregations of Autoscope data on the estimation of space-mean speeds with different length of measurement sections (5m, 10m, 15m and 20m) and measurement time intervals (20s, 30s, 60s and 120s). The results show that the space-mean speed can be better estimated by Autoscope data using 10m measurement section with a time interval of 120s.
Original languageEnglish
Title of host publicationTraffic and Transportation Studies 2010 - Proceedings of the 7th International Conference on Traffic and Transportation Studies
Number of pages10
Publication statusPublished - 25 Oct 2010
Event7th International Conference on Traffic and Transportation Studies, (ICTTS 2010) - Kunming, China
Duration: 3 Aug 20105 Aug 2010


Conference7th International Conference on Traffic and Transportation Studies, (ICTTS 2010)


  • Autoscope Video Detection System space aggregation interval
  • Space-mean speed
  • Time aggregation interval
  • Time-mean speed

ASJC Scopus subject areas

  • Mechanical Engineering

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