Impact on Driving: Drinking and Cellphones
Alex Tabarrok at Marginal Revolution discusses a study comparing cellphone users and drunk drivers that found:
When controlling for driving conditions and time on task, cell-phone drivers exhibited greater impairment than intoxicated drivers.Two possible conclusions: 1. cellphone usage affects driving or 2. legal definitions of intoxication are at levels too low to affect driving. The first conclusion is similar to those studies that show that sleep deprivation is like drunk driving. (I personally can't talk and drive at the same time, even with a hands-free set; just takes too much to focus on either.) On the second conclusion, the paper finds that legal intoxication limits don't affect driving much:
When participants were legally intoxicated, neither accident rates, nor reaction time to vehicles braking in front of the particpant, nor recovery of lost speed following braking differed significantly from baseline.This can hardly be said to be politically correct, and I'm not sure why Tabarrok thinks this conclusion is spin in the p.c. direction. However, A Stitch in Haste questions the study's methodology, and warns of the danger of writing off laws against driving under the influence. On reason I like the blogosphere - the speed of accumulation of knowledge, of arguments and counterarguments astounds me somtimes.