SAMPLING TIME AND SAMPLING ERROR IN PEDESTRIAN COUNTS

Records of pedestrian flow per minute taken over a period of time contain secular trends and random variations. Because average figures are calculated from samples containing irregular fluctuations, all estimates of mean flow rates are subject to error, the magnitude of which varies with sampling time. To isolate the effects due solely to sampling differences, the trends are removed from flow data referring to a two-hour spell in mid-morning at 11 locations. Sampling theory is used to estimate the maximum errors expected in samples of any length from one minute to two hours for different levels of pedestrian activity. Increasing the sampling time from one minute produces initially large reductions in error, which are progressively lessened. A 15-minute sampling period, for example, used to estimate a mean flow rate per minute is likely to produce maximum errors in the range 8 to 14 per cent for moderately busy streets. (A) /TRRL/

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/00410683
• Corporate Authors:

  Printerhall Limited

  29 Newmart Street
  London W1P 3PE,   England 
• Authors:
  • HAYNES, R
• Publication Date: 1977-2

Language

• English

Media Info

• Features: Figures; References;
• Pagination: p. 72-74
• Serial:
  • Traffic Engineering & Control
  • Volume: 18
  • Issue Number: N2
  • Publisher: Hemming Group, Limited
  • ISSN: 0041-0683
  • Serial URL: http://www.tecmagazine.com/

Subject/Index Terms

• TRT Terms: Average; Errors; Maximization; Numbers; Pedestrian counts; Pedestrian flow; Pedestrians; Sampling; Statistical sampling; Time
• Uncontrolled Terms: Maximum
• ITRD Terms: 6549: Average; 6440: Error; 9042: Maximum; 6432: Number; 1733: Pedestrian; 6553: Sample (stat); 5414: Time
• Subject Areas: Data and Information Technology; Highways; Operations and Traffic Management; Pedestrians and Bicyclists; Planning and Forecasting; I72: Traffic and Transport Planning;

Filing Info

• Accession Number: 00153926
• Record Type: Publication
• Source Agency: Transport and Road Research Laboratory (TRRL)
• Report/Paper Numbers: Analytic
• Files: ITRD, TRIS
• Created Date: Sep 20 1977 12:00AM