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Transportation Science

Unintended Consequences For Traffic Safety Feature 579

An anonymous reader writes: Traffic engineers had a problem to solve: too many pedestrians were getting hit by cars while using the crosswalks at intersections because they didn't know when the 'WALK' sign would change. Their solution was simple: implement a countdown timer. Countless cities have now adopted these timers, but it turns out to have an undesired consequence: motor vehicle crashes are actually increasing at intersections where the countdown timer is used. Researchers think this is because pedestrians aren't the only ones who see the timers. Drivers see them too, and it provides them with information on when the light will change. Then they anticipate the change by either speeding up to beat a change to red light, or anticipating a green light in order to get through before the pedestrians can move into the road. The researchers suggest finding some way to hide the countdown from the drivers, perhaps through the use of an audio countdown that would be difficult to hear from inside a car.
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Unintended Consequences For Traffic Safety Feature

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  • by nedlohs ( 1335013 ) on Wednesday July 02, 2014 @08:59AM (#47367747)

    It has helped. Can you not read or something?

    The timers lowered the number of accidents involving pedestrians.

    So the opposite of "not helped", it worked just fine.

    However, in addition to reducing the number of pedestrian accidents it also increased the number of rear-end collisions.

  • by Anonymous Coward on Wednesday July 02, 2014 @09:47AM (#47368063)

    Then you also take away opportunities to be a gentleman. :(

    Good. I've seen drivers behaving as "gentlemen" inadvertently cause a considerable number of near misses. Not as many as asshats cause, but quite a few. The thing is, drivers should be predictable. It might appear courteous to let someone out of a side road, but it's not usual. As soon as you start behaving differently from everyone else on the road, you cause a degree of confusion. And confusion among drivers is sometimes lethal.

    So next time you're tempted to be unnecessarily courteous, don't. The driver you want to let out of the side road will get out just the same in a minute or so, and there will be reduced opportunity for confusion among other drivers around you. The most gentlemanly and considerate thing to do overall is to drive predictably, and hopefully self driving vehicles will improve that.

  • Re:OR (Score:4, Informative)

    by bluefoxlucid ( 723572 ) on Wednesday July 02, 2014 @10:40AM (#47368539) Homepage Journal

    Because, in America, we threw out the old, broken notion of a one-hour road test and just give licenses out if you can show that you can operate a motor vehicle. The test is simple: Turn the car on. Activate the right turn signal, turn into a parking lot. Stop at stop sign by using brakes. Activate left turn signal, turn. Park. Unpark. Activate right turn signal, turn. Stop at stop sign, signal right, turn. Stop, engage parking brake, shut down engine. Congratulations: you passed your driver's test. You may now drive alone between the hours of 6am and midnight.

    Remember when we used to have Hydrostatic licenses because you didn't pass your driver's test on a manual transmission? We now let you get a license and go buy a manual car, even though you've never driven one, and drive it on the street. I did that, to the annoyance of everyone around me. My license wasn't stamped with a Hydrostatic restriction, so I could drive a car with a manual gear box despite only ever having driven with a hydrostatic torque converter.

    I have been lobbying heavily for stronger driving laws. I want to turn this place into semi-Germany, but that's a long way off; first, I want driver's education and licensing fixed. We can worry about lane control discipline, traffic calming, and stricter procedural laws later.

    Advanced driving courses teach vehicle dynamics, skid control, proper reactionary techniques to road hazards, proactive hazard evaluation, and so on; they cost $300 here, and you can go all the way to $1500 for driving/racing combined classes. Learner's permit should be 6-12 months with at least 5 hours per week of driving and 100 combined driving hours in a 6 month period or 200 combined driving hours in one year; a full license should involve a 1 hour road driving test and a half hour skidpan hazard course test. If the instructor doesn't think you're safe on the road, he can require another 12 hours of hazard and 50 hours of driving to re-apply.

    The cost of $300 for advanced driving and an hour and a half of time would be negligible. Your kid is going to need insurance; you can make him wait another 2-3 months for a driver's license, saving that $300/mo extra premium. If we pay the jackass at the DMV $100/hr, that's $150 more for the test--$450 one time to get your kid licensed. It's worth it. It's not even a real cost: we're essentially moving the age of licensing by a few months.

    I would also like to require re-licensing every 6 years. We get automatic renewals without passing any sort of paper or road test; that's bullshit, and I want you back on the hazard course in 5 years. If, at license renewal time, you haven't passed a hazard test some time in the past year, your license is suspended until you pass a hazard test.

    I dropped from 70mph to 20mph in one second today (good tires) because of other idiots on the road. I don't like running down construction workers, jackasses exiting their car into traffic, small children, or other drivers who can't fucking signal or look before they drive out in front of me; fortunately, I notice most of them before they do something stupid, and I react with precision when I fail my hazard checks.

    This is not superhuman reflex. When I check my mirrors, I pre-load all the safe places to maneuver into my brain stem and spine. When something happens, my body is already carrying out appropriate action before my brain has really decoded the message. That's how baseball players work. That's how lacrosse players work. It should damn well be how drivers work. That 99.99% of the time you spend cruising down the streets is unimportant; it's that ONE SECOND where you either flick the wheel or pulp some idiot on a skateboard that matters. The extremely low probability is significant because you'll be driving way longer than that, and the extremely high severity means this should be a primary risk focus, so why the hell aren't we hazard training our drivers?

The moon may be smaller than Earth, but it's further away.