License Plate and Telephone Numbers in Changeable Message Sign Amber Alert Messages

Studies were conducted with a driving simulator and laptop computers to determine the effects of displaying license plate and 10-digit telephone numbers in Amber (America’s Missing: Broadcast Emergency Response) alert changeable message sign messages. The first study was conducted using the Texas Transportation Institute driving environment simulator in College Station, Texas. A laboratory study was also conducted in six cities in Texas. It was found that the average reading time for Amber alert messages with a license plate number was significantly longer than for messages without a license plate number. In addition, the majority of subjects were not able to recall the entire number. A license plate number was found to be equivalent to more than three units of information. Thus a message with a license plate number exceeds current effective message design guidelines that specify a maximum of four units of information in a message and a maximum of three units of information in a message phase. Similarly, the average reading time for messages with a 10-digit telephone number is significantly longer than for messages without a telephone number. The majority of subjects were not able to recall the entire number. A telephone number was found to be equivalent to more than three units of information. A message with a 10-digit telephone number exceeds current effective message design guidelines.

• Record URL:
  https://doi.org/10.3141/2012-08
• 
• Summary URL:
  http://scholar.google.com/scholar_lookup?title=License+Plate+and+Telephone+Numbers+in+Changeable+Message+Sign+Amber+Alert+Messages&author=C.+Dudek&author=S.+Schrock&author=B.+Ullman&publication_year=2007
• Availability:
  • Find a library where document is available. Order URL: http://www.trb.org/Main/Public/Blurbs/159610.aspx
• Authors:
  • Dudek, Conrad L
  • Schrock, Steven D
  • Ullman, Brooke R
• Publication Date: 2007

Language

• English

Media Info

• Media Type: Print
• Features: Figures; References; Tables;
• Pagination: pp 64-71
• Monograph Title: Freeway Operations and High-Occupancy Vehicle Systems 2007
• Serial:
  • Transportation Research Record: Journal of the Transportation Research Board
  • Issue Number: 2012
  • Publisher: Transportation Research Board
  • ISSN: 0361-1981

Subject/Index Terms

• TRT Terms: Communication systems; Guidelines; Human factors; Information dissemination; License plates; Messages (Communications); Numbers; Variable message signs
• Identifier Terms: AMBER Alert
• Uncontrolled Terms: Telephone numbers
• Geographic Terms: Texas
• Subject Areas: Data and Information Technology; Highways; Operations and Traffic Management; Safety and Human Factors; I73: Traffic Control;

Filing Info

• Accession Number: 01049587
• Record Type: Publication
• ISBN: 9780309104388
• Files: TRIS, TRB, ATRI
• Created Date: Feb 8 2007 5:50PM