Driver
Response in Various Environments Empirically Estimated
This program is the results of an 12-year research project and is based upon the response times of drivers in research and in real traffic situations. At the present time over 155 studies (involving over 10,000 responses by subjects), 215 real traffic responses that have been video taped, and 36 Event data recorder downloads (from vehicles involved in rear end crashes) have been utilized to develop a series of equations that predict driver response times (or distances).
After looking at the equations, Dr. Paul Olson had the idea of using the adjustment coefficients as a way to adjust the results from studies to match the real world crash scenario. Therefore, a second type of research was conducted, which is referred to as Adjustment-to-Baseline [A2B]. With A2B, the methodology of each study is compared to the conditions entered by the user and if necessary an adjustment is made. For instance, Olson & Sivak (1986) conducted a study in daylight and stopped the clock when the foot hit the brake. Therefore, in a real life crash situation at night, we would have to make an adjustment to Olson & Sivak’s result for the difference between day and night and we would also have to account for the braking time (time from brake application to skid marks). DRIVE3 does this with as many as 17 studies.
When the average of all adjusted studies and the results of the equation are averaged, the resulting “Normal Response Time” is within 0.4 seconds of the actual response time for that scenario (from real world crashes and near crashes). This means that if 10 people were all exposed to that same situation, the average response time would be within 0.4 seconds of the normal response time. If we look at the ability to predict the next individual (who may be blind, drunk and on the cell phone or very luckily looking in the perfect location), DRIVE3 will estimate the individual response time of the middle 2/3rds of all drivers (everyone but the very worst or very best) within 35% of the Normal Response Time.
As with any scientific method, there are limitations to this program in research will always be ongoing and the user must use the tool properly. However, at the present time, this program offers the only two methods of driver response estimation that are empirically tested to be able to reasonably estimate response time of real drivers.
The research upon which this program is based has been peer reviewed by the University of Hartford psychology and engineering departments and the Society of Automotive Engineers before being published. Jeff Muttart has received the Wallace Award for excellence in research and the Graduate Research Award at the University of Hartford for this research. This program is being used by over 500 traffic accident reconstructionists, police officers, and forensic engineers in 9 different countries. Also, more than 250 crash reconstructionists have attended a DRIVE3 instructional course taught by Jeff Muttart.
DRIVE3 results represent how drivers HAVE responded to emergency situations. It is based directly on published and peer reviewed research, it is accepted in the field (over 500 users in 9 countries) and DRIVE3 offers the “error rate”. Therefore, DRIVE3 has never failed to be accepted in any court. Crash reconstructionists throughout the US, and Canada and I have been told that it has been accepted in New Zealand, Australia and Singapore. In many cases, the experts from both sides of the case are using the program. Furthermore, there have been instances that experts have not been allowed testify regarding driver response issues because they were not using an empirical methodology offered by DRIVE3. Such cases usually involve an expert who cites a single author from a single book or study and claims that their opinion regarding response time is based upon that author and cannot cite the methodology of that study (or that study has a much different stimulus-response scenario than the given case). DRIVE3 will eliminate that potential stress in that it will show you the methodology of several analogous research studies, it will show you where it made adjustments. It will offer a result based upon the research of Muttart and it will offer both error rate and Monte Carlo (Bootstrap) analysis. Most of all, it will show you that when drivers are faced with an emergency response scenario, they are very predictable.
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