GPS Study Shows Drivers Will Slow Down, At A Cost

Jun 21, 2012
Originally published on June 21, 2012 12:06 pm

Some 12,000 Americans die every year in traffic crashes caused by speeding, according to government statistics. Officials have tried many strategies to get drivers to slow down. And now they might have found something that works, after researchers placed a GPS device inside cars that gives drivers an incentive not to speed.

Traffic safety experts have tried using big flashing signs to tell you how fast you're going. (The psychological subtext: Drivers are rational, and they will slow down if they know how fast they're going.)

When that didn't work, they tried putting cops on your tail. (Subtext: If you make the penalty for speeding large enough, drivers will slow down.)

When that failed, they installed hidden speeding cameras on major roads. (If you don't know when you're being watched, you're more likely to drive cautiously all the time.)

The next iteration of the battle between speedsters and authorities may involve putting the cop right inside your car — and a psychologist in the back seat.

Researchers have found that a small GPS-based device that constantly measures the speed of a car against the posted speed limit can slow drivers down, if it's paired with the right financial incentive.

In a "proof-of-concept" experiment partly funded by the National Highway Traffic Safety Administration, researchers found that drivers slow down dramatically when they are promised a $25 prize at the end of each week of safe driving.

The catch: Every time the test subjects went five to eight mph above the speed limit, they lost 3 cents from their prize. And every time they went nine or more mph above the speed limit, they lost 6 cents.

"We found that the incentive system was incredibly effective in getting drivers to reduce their speeding," says Ian Reagan, a traffic safety researcher at NHTSA. "Egregious speed limit violations were almost eliminated — that's driving nine or more [miles per hour] over the speed limit."

Reagan thinks the drivers slowed down because of both carrot and stick: the prize at the end of the week for good driving, and the small penalties for speeding.

For decades now, psychological studies have suggested that people are vigilant about small, accumulating losses — the so-called "ticking meter" phenomenon. But there could be another factor involved. For some drivers, Reagan said, the challenge of "beating the game" could offer an incentive to slow down.

"At least one driver said they made a game out of it," he says. "They wanted to see if they could keep that incentive amount of $25."

Reagan thinks insurance companies might one day offer the tracking devices to drivers who wish to lower their premiums. Many companies currently offer rebates for good driving behavior.

Unlike the way insurance rebates are currently configured, the devices Reagan and his colleagues used gave drivers real-time feedback — every time drivers turned off the ignition, they were informed about the "cost" of that trip.

Stay tuned for that call from your friendly agent.

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It's MORNING EDITION, from NPR News. I'm Steve Inskeep.


And I'm Renee Montagne. Good morning.

Let's hear now about a possibly way to persuade some drivers to slow down to the speed limit. About 12,000 Americans die every year in traffic crashes caused by speeding. And now federal researchers think they have found something that could really be a deterrent. NPR's Shankar Vedantam regularly joins us to share interesting social science research. And he's here this morning.



MONTAGNE: Well, what's the magic formula?

VEDANTAM: Well, apparently the magic formula is not the big, dramatic warnings or having cops on your tail, or even speeding cameras. What these researchers did was they attached these little devices to cars that essentially used GPS technology to keep track of how fast the car was going. And these little devices also were able to monitor what the speed limit was supposed to be on the specific road that the drivers were driving on.

And the researchers found that when they attached these devices and they gave the drivers a special financial incentive, this really prompted people to slow down.

MONTAGNE: So, obviously, these are subjects in a study. But you're saying that you just pay people to slow down.

VEDANTAM: Well, they designed the financial incentive in a really interesting fashion. What they did was they gave people $25 to begin with. And they said that if you reach the end of the week with a perfect driving record, you get to keep the $25. But every time the drivers went a little bit above the speed limit, the researchers took away some of their money. So they took away three to six cents every time the drivers went above the speed limit.

Now, I spoke with Ian Reagan. He's a safety researcher at the National Highway Traffic Safety Administration. He was the lead researcher on the study. And he told me the program really worked.

IAN REAGAN: We found that the incentive system was incredibly effective in getting drivers to reduce their speeding. Egregious speed limit violations were almost eliminated. That's driving nine or more over the speed limit.

MONTAGNE: Even though it sounds like such a tiny amount of money.

VEDANTAM: Well, I think this is one of the really fascinating things about this study, which is when you think about the disincentive that a speeding ticket can give you - you know, you can get a ticket for $150 - and people still disregard that kind of incentive.

What I find really interesting here is that the penalty is so small. And, in fact, there is psychological research that shows that people are very vigilant to small losses of wealth or money. And so when you take away the small amounts of money - three cents at a time, six cents at a time - but you're giving people feedback that they are losing this small amount of money, it seems to have a very strong effect on their behavior.

And what I find really interesting about the experiment that Reagan did is that the behavior of the drivers changed not just because they wanted to follow the speed limit or get a financial incentive, but because at some level, they were enjoying the challenge of the exercise that Reagan was placing before them. Here he is.

REAGAN: At least one driver said they made a game out of it. They basically wanted to see if they could keep that incentive amount at $25.

VEDANTAM: Reagan is essentially using different psychological biases. So the pleasure that we have at playing a game or our reluctance to see the meter ticking and, you know, small amounts or small penalties being added to us to counter the other kinds of biases that make people drive unsafely - you know, the carelessness that they feel or boredom on the road or road rage.

And Reagan thinks that eventually, this kind of system could potentially be put into use in the real world, perhaps by linking these devices with the kind of premiums that drivers pay to their insurance companies.

MONTAGNE: Although, if you link them to insurance companies, you don't get that sort of immediate feedback that you were just talking about. They would not hear, theoretically, from the insurance company for every time they got in their car and got out of their car, what they'd been doing.

VEDANTAM: I think that's exactly right. So, I mean, insurance companies currently give drivers all kinds of rebates for safe driving. But the rebates are tied to your, you know, monthly premium or your annual premium. And I think what Reagan's study is showing is the power of communicating to people on a real-time basis, you know, the reaction to their behavior.

So I think if an insurance company were to figure out a system whereby people got feedback more or less in real time, telling them here's how much your last trip cost you in terms of your insurance premium, and it goes up or down depending on how fast they're driving, it could have a real effect on their behavior.

MONTAGNE: Shankar, thank you very much.

VEDANTAM: Thanks, Renee.

MONTAGNE: That's Shankar Vedantam, who regularly joins us to talk about interesting research from psychology and other fields. You can follow him on Twitter @hiddenbrain. And while you're at it, you can follow this program @MORNINGEDITION. Transcript provided by NPR, Copyright NPR.