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Overcoming Bias Commenter's avatar

According to the WHO 2004 estimates, the total amount of DALYs due to road accidents is 985 per hundred thousand. This compares to a total of 1,384 for cancers for example.I am reading this blog for the first time in years, and I have noticed that Robin has talked about health economics. But maybe this suggests we should be concentrating more on road safety than certain health priorities? The speed vs safety elasticity is certainly an interesting question, but you have to also consider effects of commuting times. Such as behavioural effects - choosing where to live and work.

Some people may actually enjoy their commutes, their private time to listen to music, or chat socially with friends. Perhaps the time spent commuting time lets us process our thoughts for the day. Who knows, but there are lots of questions that can be asked.

Admittedly I'm also an aggressive driver with a turbocharged car and I agree with Robin's behavioural characterisation of aggressive drivers.

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Overcoming Bias Commenter's avatar

Aggressive driving works well inside cities (off the highway.) A study I saw about 5yrs ago found that, worldwide, cities with more aggressive drivers had much higher avg traffic flow.

Only trouble is, aggressive driving only works on highways outside the city grid when the road is relatively empty. When it's congested, traffic jams are almost entirely due to the common aggressive behaviors: tailgating and lane switching. The jam shown in http://www.trafficwaves.org video is caused by a fight between mergers versus blockers (or "cheaters" versus "vigilantes.") If those drivers opened up and tried to attain "zipper" merging, those lanes would flow fast like gear teeth.

If you want to drive fast in congested traffic, the best tactic is to avoid triggering traffic jams: temporarily suppress aggressive behavior. One website likened this to the "Gravel-pit Etiquette" used by professional drivers in large construction projects. In those situations the "cheaters" will end up getting fired. By trying to get a couple positions ahead, they completely foul up the overall flow, and the rapid moving "gear teeth" patterns all grind to a halt.

On congested highways it's *impossible* to drive faster than average. For example, during rush hour the cars are spaced 1-2 seconds apart, so in order to shave 5min off your commute, you'd have to pass 300-600 other drivers. WEIRD, EH? If you're not passing hundreds of other cars, then you're not driving faster. That's where dishonest human nature cuts in: we abandon our goal of actually getting to work earlier. Instead we try to pass a handful of other drivers, and if successful, we congratulate ourselves as if we're winners in a race. In a race, ten positions ahead is significant. You might come in first rather than being ten cars back. But on a commute, ten positions is completely insignificant: it's shaving 10 or 20sec off your commute.

The trick is to judge when aggressive driving works, and when it's counterproductive. On key to this is to notice "race mentality" in yourself. On open highways you can speed, and easily pass hundreds of other drivers in an hour of driving. But as soon as you notice yourself working to get one car ahead, or notice that "my position in line" has become important, that's when attempts to drive faster will only throw a wrench in the gears.

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