The Traffic Conflicts Technique was developed by General Motors Research Research Labs as a method of measuring accident potential during the early 1960's. The Technique is based upon tabulation of evasive maneuvers at intersections as evidenced by brake light indications or lane changes. For the purpose of measuring accident potential at intersections, some twenty-odd specific conflict classifications are defined and coded on computer keypunch forms. As a result of an FHWA financed research program, the State of Ohio become involved in the evaluation of the Conflicts Technique during 1969. At the time that the Federal Program ended in 1971, Ohio decided to pursue its own evaluation of the technique. This decision was prompted by a conviction that the theory behind the Conflicts Technique was sound and a belief that it could be used to find an accident projection technique for use in Ohio. In order to be useful, an accident projection technique must reflect the accident trends of the subject area. Early tests indicated that the projection algorithm published by FHWA could not be easily calibrated for Ohio data trends. Although Ohio data was utilized in generation of the FHWA method of accident prediction, it was felt that the data from the other states that submitted data, namely Virginia and Washington, was of such volume and different nature as to bias the resulting algorithm away from the accident trends found in Ohio. During 1972 and the first half of 1973, the Ohio data base was enlarged from 196 projects collected under the FHWA Program to 410 projects, thus providing 992 approaches of data, of which, 611 were usable for analysis purposes. A series of regression models were applied to this enlarged data base in an attempt to find a reliable accident prediction model. As a result of the regression analysis, accident prediction algorithms were developed which provide a mean accuracy of plus or minus 1.1 accidents per year and a 75 percentile accuracy of plus or minus 1.8 accidents per year. In addition, substantial insight was gained into the workings of the Conflicts Technique and its underlying theories. With this understanding of the Conflicts Technique and appreciation of the theory of conflicts came new questions and areas for future study. As a result, Ohio intends to continue its use and evaluation of the Traffic Conflicts Technique and hopes to eventually provide the Traffic Engineer with a versatile tool for the evaluation of traffic flow efficiency and accident potential.

  • Corporate Authors:

    Ohio Department of Transportation

    Bureau of Traffic, 25 South Front Street
    Columbus, OH  United States  43215
  • Authors:
    • Paddock, R D
  • Publication Date: 1974-3

Media Info

  • Features: Figures; References; Tables;
  • Pagination: 171 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00080730
  • Record Type: Publication
  • Source Agency: National Safety Council Safety Research Info Serv
  • Created Date: Mar 26 1975 12:00AM