Paper Details

TRB 91st Annual Meeting (January 22-26, 2012)

Event Number:	648
Event Title:	Highway Safety Performance
Event Date:	Jan 24 2012 7:30PM- 9:30PM
Event Location:	Marriott, Salon 2
Event Description:
Event Agenda:

Crash Modification Factors: Foundational Issues (12-0326)

Crash Modification Factors (CMFs) are listed in the Highway Safety Manual (HSM) and other authoritative publications. Using these one cannot distinguish predictions of safety effect that can be made confidently and are likely to lead correct decisions from those that lead to decisions that can easily be wrong. Nor can one know how transferable are past research results from some circumstances to decisions about future actions to be implemented in different circumstances. The conceptual framework described in this paper aims to be of guidance for future research about CMFs and to meta-analyses thereof. The central claim is that CMFs are random variables with a mean and a standard deviation; that they are not universal constants that apply everywhere and at all times. The smaller the standard deviation of a CMF the more confident can be the related decision-making. Therefore, the aim of research about CMFs is to reduce their standard deviations. Ways to do so efficiently are indicated. The requisite theory and equations are provided.

Authors
     Hauer, Ezra , University of Toronto, Canada
     Bonneson, James A., Kittelson & Associates, Inc.
     Council, Forrest M., University of North Carolina, Chapel Hill
     Srinivasan, Raghavan , University of North Carolina, Chapel Hill
     Zegeer, Charles V., University of North Carolina, Chapel Hill