3 ms·
This is well-studied. It turns out that the 85th percentile speed (the speed where 85% of drivers are below that speed, 15% above) is nearly insensitive to spee
by URSpider94 9y ago
This is well-studied. It turns out that the 85th percentile speed (the speed where 85% of drivers are below that speed, 15% above) is nearly insensitive to speed limit. Road design is the biggest single determinant of travel speed. http://www.lsp.org/pdf/troopc85thSpeed.pdf http://www.lsp.org/pdf/troopc85thSpeed.pdf
- franciscop 9y agoAmazing insights: > Won’t raising the speed limit cause people to drive faster and cause more crashes? > The Federal Highway Administration studied nearly 200 roads in 22 states where speed limits were raised, lowered or left unchanged. Prior to the speed limit change, 55 percent of drivers exceeded the posted speed limits. After speed limits were raised or lowered as much as 20 mph, there was a slight change in speed, but generally less than 1 mph. There were no significant changes in crashes, although crashes tended to decrease where speed limits were increased to realistic levels. Also, there was little effect on speeds or crashes on intersecting or nearby roadways.
- emj 9y agoThis is for federal highways, traffic in a city should not go faster than 25mph in most shared spaces. Motorways is a different subject, but there should only be overpasses or resegined roads and traffic lights for such places.