Eyewitness Speed Estimates, Papers & Book

[MSI]

Some references on Eyewitness Speed Estimates posted to INCR forum added here for easy reference/review:

• 2020 Underestimation tendencies of vehicle speed by pedestrians when crossing unmarked roadway
  
  • Zoran Papic, Andrijana Jovic, Milan Simeunovic, Nenad Saulic, Milan Lazarevic
    Abstract
    To make safe road crossing decisions, the pedestrians need to estimate the distance and speed of oncoming vehicles, in order to make conclusions about the available time gap they need for their road crossing. Since the speed represents combination of distance and time, we focused on pedestrians’ ability to estimate the speed of the oncoming vehicles accurately. The aim of this study was to find some characteristics important for the speed mis-estimation tendencies and its values. Seventy participants estimated speed 3920 times in total. Research included three experiments. One vehicle participated in the first experiment, while second and third experiments involved two vehicles, with various combinations of vehicle positions and speeds. Initially it was determined that the pedestrians had tendencies to speed underestimation rather than its overestimation and accurate estimation. When the participants estimated the speed of one vehicle, they were more inclined to underestimation of higher speeds (over 50 km/h). On the other hand, in the situations where the participants estimated the speed of two vehicles, they showed a serious tendency towards underestimation of lower speeds (under 50 km/h) which was completely opposite. The factors such as driving experience, age and gender were identified as statistically important in terms of speed underestimation value. We determined that an increase in task complexity, with introduction of a larger number of vehicles, resulted in more severe speed underestimation. Finally, we identified some of the most risky traffic situations in terms of speed underestimation tendencies showed by our participants.
• 2013 The Accuracy of Pedestrians in Estimating the Speed of a Moving Vehicle
  
  • SAE paper 2013-01-0785
    This study was performed in order to evaluate the accuracy with which pedestrians estimate the speed of nearby automobiles. A total of 87 subjects were involved in this experiment, with 487 useful speed estimates being obtained from them. The vehicle speeds were measured using radar guns, and the moving cars were located upstream, downstream, and adjacent to the subjects. A survey form was used to obtain attributes about each subject. A multivariate regression was used to allocate portions of the variation in the percent error among the various factors that describe the subject and the moving vehicle. Statistical significance was discovered for the main effects and some interactions among: gender, driving experience, a self-assessment of ability to estimate such speeds, the use of the posted speed limit, the speed of the target vehicle, and the location of the vehicle on the roadway. The implications for speed estimation accuracy are presented, both for categories of subjects and for individual subjects. The standard deviation in the accuracy of individuals was remarkable for its large magnitude and its persistence over all the categories of subjects and also the different vehicle speeds and locations.
• 2012 ARRB conf 2012 - witness speed estimates
  • ABSTRACT
    • It is intuitive that the overall safety of a road network (and indeed, other transport systems) is
      highly reliant upon its users making sound assessments of the speed, orientation and direction
      of travel of fellow users, for example when crossing the road as a pedestrian or when
      negotiating an intersection as a car driver.
      Additionally, how accurately and reliably people estimate the speed of moving vehicles when
      viewed from different angles, and at what angles estimates of speed are typically mo st accurate
      are of considerable interest when considering the role and implications of eye witness (lay)
      evidence in the conduct of police investigations in criminal and civil legal cases.
      Considerable research and experiment ha
      ve been conducted into bot h of the aforementioned
      areas, with specific interest tending to be in the sex, age and experience of observers, and the
      specification of vehicles used although it appears that much of it has been undertaken outside
      of Australia. This paper details resea rch conducted as part of the test track day of the 3 rd
      International Road Surface Friction Conference, which was held in Australia in May 2011.
    CONCLUSIONS
    • The authors hope that the outcomes of this research
      wi ll be of use to practitioners with an
      interest in the accuracy and reliability of eye witness recollections, especially where eye
      witnesses are asked to provide their best estim ate of the speed of a vehicle. The six ( 6 test
      runs conducted during this experiment allowed consideration of a number of viewing positions /
      orientations of a vehicle.
      The authors believe that the results obtained from this research are consistent with
      the majority
      of past research identified in these areas, namely:
      • Eye witness estimates of vehicle speed are not grossly inaccurate per se and tend to
        spread reasonably precisely around a mean (average) value that is close to the measured
        speed.
      • Although th e majority of observations were found to be within one standard deviation of the
        measured value, individual outlier estimates can however vary by up to nearly 100% of the
        measured value, and can be either an under, or over estimate
      • The range of speed esti mates found for a particular test run tend s to be largest at the
        highest vehicle speeds
      • There appears to be a general tendency for eye witnesses to under estimate the highest
        vehicle speeds and over estimate the lowest vehicle speeds, but this was not fou nd to be a
        uniform (consistent) and reliable rule
      • Accurately estimating the speed of a vehicle is most difficult to achieve when th e vehicle is
        travelling perpendicular to the viewing positions (i.e. directly towards or away from the
        delegate’s viewing po sition)
      • Extra stimulus factors (such as driving aggressively and/or using high revs) do appear to
        lead to delegates slightly over estimating the vehicle speed all other things being equal.
• 2009 Eyewitness Reliability in Motor Vehicle Crashes: A Primer for Practitioners
  • 2nd edition, by Patrick J. Robins
    Eyewitnesses, especially in testimony, can be a mess. Two witnesses can contradict one another over the same accident scene. Some acquire post-event misinformation. And human memory, always unreliable, plays a crucial role. Now you can be prepared with this book, exploring all the fallible aspects of eyewitness testimony. You will learn how a jury evaluates eyewitness testimony on the basis of witness confidence and personality. This book teaches you to counteract this by knowing what questions to ask your witnesses to get the most accurate information, where to undermine the eyewitness testimony against you, and how to avoid the pitfalls of eyewitness evidence. Dr. Robins cites case studies, research, and seminar demonstrations that are both interesting and educational. By learning from one of the world's experts, you will make eyewitness testimony an asset to your case.
• 2007 Vehicle Speed Determination from Fuzzy Evidence in a Multiple Pedestrian Collision,
  • Stevenson, T.; Raine, J.:, IMPACT, The Journal of the ITAI, Vol. 18 No 2 - Summer 2010.
    • A number of methods of analysis were used to examine an incident where a vehicle struck a number
      of pedestrians on Edgeware Road, Christchurch on 5 May 2007.
      While conventional estimation of pedestrian impact speeds was not possible because of gross
      uncertainty around throw distances, the combination of methods covered in this paper were
      considered to give a consistent and ultimately reliable estimate of the vehicle speed during two
      significant phases of its travel and collision sequence with pedestrians