4 ms·

>When the speed limit is correctly set at the 85th percentile speed, the minority of drivers that do conscientiously follow speed limits are no longer driving m

>When the speed limit is correctly set at the 85th percentile speed, the minority of drivers that do conscientiously follow speed limits are no longer driving much slower than the speed of traffic. The choice of the 85th percentile speed is a data-driven conclusion -- as noted Lt. Megge and speed limit resources like the Michigan State Police’s guide -- that has been established by the consistent findings of years of traffic studies. >This is important because, as noted in a U.S. Department of Transportation report, “the potential for being involved in an accident is highest when traveling at speed much lower or much higher than the majority of motorists.”

LoSboccacc 9y ago
And again, because everyone thinks a speed it's safe doesn't mean a speed it's safe. People may believe it is, but phisics laws are hard to fool. Meanwhile people are well known to not understand risk and probability.
- u801e 9y ago
  Posting speed limits that reflect actual traffic speeds decreases speed variance and decreases the frequency of crashes. That's actually safer.
  - LoSboccacc 9y ago
    speed and severity of crashes correlation is quite established in literature, so I'm gonna wait for a study to come up with conclusive statistical data stating speed variance correlates more with injuries than absolute speed. until then, it's conjecture, feelings and wishful thinking. edit: then again urban and highway situations are different, so there's that. but you have truck and slow traffic on the highway anyway thus increasing car limit does increase speed variation in that situation and would be detrimental whether variance or absolute speed are considered
    - u801e 9y ago
      > speed and severity of crashes correlation is quite established in literature, so I'm gonna wait for a study to come up with conclusive statistical data stating speed variance correlates more with injuries than absolute speed. That is if a crash happens. If you compare crash rates and fatality rates on limited access highways where speeds are higher to other types of roads, you'll find that the former is lower on both counts. > but you have truck and slow traffic on the highway anyway Trucks do not drive that much slower than cars unless they're going uphill or have a speed limiter. With higher speed limits, slower traffic will most likely speed up to some extent and trucking companies may remove their limiters (or increase the speed where they kick in).
obstinate 9y ago
Which studies? What did they show? Again, the fact that some guy claims a study shows he is right does not count for evidence.

LoSboccacc 9y ago

And again, because everyone thinks a speed it's safe doesn't mean a speed it's safe. People may believe it is, but phisics laws are hard to fool. Meanwhile people are well known to not understand risk and probability.

u801e 9y ago
Posting speed limits that reflect actual traffic speeds decreases speed variance and decreases the frequency of crashes. That's actually safer.
- LoSboccacc 9y ago
  speed and severity of crashes correlation is quite established in literature, so I'm gonna wait for a study to come up with conclusive statistical data stating speed variance correlates more with injuries than absolute speed. until then, it's conjecture, feelings and wishful thinking. edit: then again urban and highway situations are different, so there's that. but you have truck and slow traffic on the highway anyway thus increasing car limit does increase speed variation in that situation and would be detrimental whether variance or absolute speed are considered
  - u801e 9y ago
    > speed and severity of crashes correlation is quite established in literature, so I'm gonna wait for a study to come up with conclusive statistical data stating speed variance correlates more with injuries than absolute speed. That is if a crash happens. If you compare crash rates and fatality rates on limited access highways where speeds are higher to other types of roads, you'll find that the former is lower on both counts. > but you have truck and slow traffic on the highway anyway Trucks do not drive that much slower than cars unless they're going uphill or have a speed limiter. With higher speed limits, slower traffic will most likely speed up to some extent and trucking companies may remove their limiters (or increase the speed where they kick in).

obstinate 9y ago

Which studies? What did they show? Again, the fact that some guy claims a study shows he is right does not count for evidence.