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Olson v Baker Driver Perception/Response Times

Posted: Mon Nov 09, 2015 1:06 pm
by MSI
Q: I would like to gather opinions on the merits or applicability in casework of perception-reaction time as defined by Paul Olson in "Forensic aspects of driver perception and response" (2010) versus that by J Stan Baker in "Perception and reaction in traffic crashes". I was told that Baker's definition had an advantage in reducing ambiguity regarding which point a hazard can be considered perceptible to a driver. However I am skeptical as definitions of PRT include similar components (however named or categorized) which need to be accounted for. When PRT starts is often quite a challenge.

A: Since we've been buried in preparing and releasing our msmac3D software we've been somewhat out of the loop on the most recent developments in driver preception/reaction studies. Particularly now with many studies which incorporate built in video systems so actual crashes (as opposed to laboratory or staged settings) are being investigated.
For example, SAE 2005-01-0426 Factors that Influence Drivers' Response Choice Decisions in Video Recorded Crashes.
We recommend you contact Jeffrey Muttart and/or Crash Safety Research and/or Crash Safety Solutions.
They specialize in driver perception/response and all things driver related and so might point you to papers which may include reviews and comparisons of Olson vs Baker.
I will also drop Jeff an email and post up any response i get from him on your question.

Re: Olson v Baker Driver Perception/Response Times

Posted: Fri Nov 13, 2015 9:55 am
by MSI
I received the following response from Jeffrey Muttart, Crash Safety Research Center, LLC.
Thank you Jeff!
  • As the person responsible for all Human Factors curriculum at NU-CPS, we recognize that the "Fricke" book must be updated. Anyone still using a Baker book is using outdated information.
    I will be rewriting the human factors chapter. Dr. Olson is a respected colleague but you cannot take his results verbatim (he would agree). As Daubert tells us...
    • We must use accepted research or methods...
      And we must apply it properly.
    Olson and Sivak measured brake response to a yellow piece of foam 150 ft. Ahead after cresting the knoll of a hill. In general, there are a few common PRTs
    • Day- straight road - 1.8 sec +\- 0.7 sec
    • Day- non-straight (intersection, curve, crossing guard, etc) 1.3 sec +\- 0.5 sec
    • Night- straight - 2.1 +\- 0.8 sec
    • Night - non straight - 1.6 +\- 0.7 sec
    • Two cars following closely behind and front car brakes 1 sec +\- 0.3 sec
    • Two cars, one stopped and the other approaches at high speed- get a human factors expert / this is a longer PRT many times.
    • Being cut off In Traffic 1.0 sec +\- 0.5 sec
    Each of these instances are rules of thumb -
    • a thorough analysis of all objective factors will likely be better than a rule of thumb -
      I encourage people to attend the class at Northwestern.
    I will only ask - how do you know what you don't know? Much of what I teach, no recon knows about, but I think most will agree that the information addresses information for every case.
Thank you again Jeff!

Re: Olson v Baker Driver Perception/Response Times

Posted: Fri Nov 13, 2015 10:35 am
by MSI
And let me add a little more information on the type of class Jeffrey W Muttart teaches:
  • Advanced Crash Reconstruction Utilizing Human Factors Research
    The class includes Jeff teaching:
    • 1. How acceleration choice changes
      • - lateral
        - forward
        - backing
      2. PRT - as stated
      3. Night recognition
      4. Whether a driver pulls out or not
      • probabilities given the presence of an approaching vehicle at a given distance
      5. Pedestrian walking/running speed at intersections/mid-block
      • in good weather and bad, when violating a signal and when not
      6. Drivers ability to estimate closing speed
    and much more...
See Advanced Crash Reconstruction Utilizing Human Factors Research for additional information