Traffic safety “nudges” can cause number of crashes to increase (2022)
science.org
science.org
But how do we know a different color might not save lives? Only half joking.
What if yellow cures everyone?
Everything is cured and everyone is happy.
[0]: https://goodui.org/leaks/google-has-been-a-b-testing-link-co...
50 cm above the floor the wall had 6 washed out grayish colored bars 20-25 cm width with green and orange slightly brighter. I didn't notice a productivity gain but it did allow excellent peripheral vision.
Were the bars vertically oriented or horizontally oriented?
"I worked so hard so that this exact thing wouldn't happen"
It could be that the warning color added subconscious stress to doctors and patients alike.
Green has a soothing, calming effect on people because it's most common in our natural surroundings. For example, TV shows use "green rooms" filled with plants (and sometimes even painted green) to calm down guests before they go on stage for this very reason.
Orange, on the other hand, excites people and can elevate their heartbeat. It's a cross between red (hot-blooded, passion, rage) and yellow (energy, happiness, attention). You could say it encourages your emotions to interfere with rational thought.
So you can keep your appetite for large-scale redesigns! Just add a step to incorporate color psychology.
Irony...
What happens if you try to make an http call from the dialog?
"Our infotainment system is a danger for anyone to use because of the terrible design. Please press "I agree" to confirm it is all your fault and responsibility somehow." Mercifully but even more ridiculous, it just goes away without being pressed when you start driving.
Some don't, I'm afraid to say.
"If you ignore this automatic popup warning in order to focus on driving, the screen will continue to display the message indefinitely at maximum brightness to distract or blind you for your entire trip until you take your attention away from the road to turn it off."
My car's crash safety rating was significantly dinged because lower trim lines don't have low beams that follow the steering.
I wish they'd deduct a star for "there is a circumstance in which the car is on, and the main console is displaying a non-time-critical-popup, or refusing to accept input".
On a related note, why do car manufacturers make you come to a complete stop on the freeway so the person in the passenger seat can type an address into the navigation system?
I have to wonder whether adding friction to the UX in the name of safety can have the complete opposite effect. Sure, drivers might do something dumb like trying to pair a Bluetooth device while they're driving, but if the car makes this impossible, isn't it increasing the amount of time the driver is distracted?
I have GPS in my car, but I use an external one because the internal one is so annoying this way - the first time I got lost because my passenger could not interact with the GPS was also the last time I used it.
The GP is taking the nanny-ware as a given, and narrowly asking why the passenger isn't allowed to bypass it.
I'm pointing out that cars don't have a is_occupied_by_human(), just car_seat_weight() and seat_belt_in_use(). That it works this way isn't obvious to anyone who hasn't looked into it.
Um, except they actually do, and its used to control safety-related equipment (passenger=side airbag), safety notifications (passenger airbag and seatbelt lights), and alarms (passenger seatbelt not in use when seat occupied alarm).
It may not be wired into the infotainment system, though.
"I'm a good multitasker! I can do this perfectly safely! Why shouldn't I? Cops do it all the time!"
Every time I've seen this sorta subject come up on car-related forums there's a non-negligible amount of people who carry an opinion like that.
Putting a nanny on a car is just stupid. Especially because, surprise, surprise, passengers actually do sometimes ride in cars!
This is simply not the job of the car.
I've seen someone on this site call for the abolition of drunk driving laws, arguing that the punishable act should be driving recklessly rather than the factors that led to the reckless driving; because of course, if you think you can drive drunk safely, then why shouldn't you be allowed to (/s)?
Sure if you can demonstrate that you can do X activity safely it seems reasonable to allow you to do so. However, that hasn't been demonstrated.
E.g. sleeping off your drunkenness while sitting in the front seat with the keys within reach. Starting the car to run the heater or AC might get you additional punishment.
It's bizarre - it ought to occur to such people that ordinary folks cannot function with six or eight beers in the head, and that they ought to seek treatment for their condition but it just doesn't. No tolerance for alcohol behind the wheel.
Is there some flaw in the argument? Typically it's the reckless driving which would get you caught anyway. Which is why the "I'm fine" crowd still does it despite it being illegal -- they think they're not going to do anything that will get them pulled over.
The advantage of that proposal isn't that the drunks get away with it. If they're weaving in and out of lanes or driving 35 on the highway they're still getting cited.
It's that the person doing the exact same thing because they're excessively tired or otherwise incapacitated gets the same citation even if they can blow in the machine and get a zero.
It can cause someone else to hit you.
And the example was driving under the minimum speed.
(Almost every modern car knows when there is a passenger in the front passenger seat — they could feed this knowledge to the infotainment system.)
They're supposed to blank the video out when the car is moving (going audio-only), but your dealer will pretty much by default pull the one sense wire on the back of the unit that causes it to do that so you can watch TV when driving, since that's what everyone wants.
Now here comes the interesting part - despite having the sense wire pulled so that it can play video while in motion, it will still disable the settings menu when the car is moving. So there must be a second sense wire somewhere in the wiring harness that it's using for the "real" safety feature, while leaving a sacrificial sense wire for the feature everyone will disable anyway. Very bizarre.
However, that doesn’t change the fact that the warning label “CAUTION: Contents hot” on a paper cup is indeed pretty useless and likely exists as a result of this lawsuit — not because it will actually keep anyone from burning themselves (for that goal, you’d want it to say some variant of “our coffee is much hotter than what you make at home”), but because a bunch of lawyers thought it would make for an easier defense next time.
That’s the root cause right there.
- traffic messages that are displayed by rotating through three or more screens; two is fine if necessary, as you can ingest all of it in short order; but to keep staring at it waiting for the third screen is just way too dangerous
- digital advertising billboards, for the same reason; these are even worse because the ads are generally poorly designed with tiny fonts that are hard to read at a glance
I have a strong preference for an analog speedometer for the same reasons. In an instant your eyes can discern whether you are accelerating or decelerating. On a digital display, with a measly 1 MPH resolution, you have to keep looking down over and over to determine if you are maintaining your speed.
If you are accelerating at 1 mph per second, it can take up to an entire second for the digital display to indicate that you are accelerating at all, and, even then, you still don't know how fast you are accelerating. The resolution just isn't good enough.
Maybe under ideal conditions. Not while driving. And below .25 is still enough to have you drift off speed.
> you definitely would be aware that you are accelerating and whether your efforts to compensate are increasing or decreasing it.
It is by no means definite. It's very easy to drift off the correct speed when e.g. the slope of the road changes, even if you're trying not to.
https://www.varaosahaku.fi/image/900/a/85/d62c83/path/mnt/ne...
Their dependent variable is the number of crashes per hour, scaled by the "population average" for segments of the same length. I guess this is fine so long as you look at the same areas. They give two tests to try and control. One is checking upstream crashes but I kind of suspect the signage is positioned where you're supposed to be extra careful due to increase risk, so that may not be relevant. The other is looking at the same areas before and after. This does seem like a fair argument.
They also include specific effects for exact date-hour combos, but I feel like this is a bad approach as you would want to ideally capture higher level weekday + hour seasonality traits; not specific date hours.
They say on the multi variate: > In particular, we show that clustering by segment-year-month reduces the standard error in half, clustering by just geography produces slightly smaller standard errors, controlling for rain more flexibly does not affect our results, not controlling at all for rain doubles our estimated treatment effect, not controlling for holidays increases our estimate slightly, and dropping hours immediately before and after campaign weeks (i.e., hours outside of campaign weeks that sometimes display fatality messages, see fig. S6) further increases our estimate
Which implies a lot of it may be random sample bias of the test set all being on worse weather days, even if they try to control for it here.
Regardless. I think it's a plausible analysis. The effect size is just 1-2% though.
Presumably, if the sign is displaying "congestion ahead" warnings, then traffic has often already slowed to a crawl, which could lead to a few percentage point decrease in crashes.
Also, unless the signs were placed poorly, they're likely in high-congestion areas, and frequently toggling between normal and congested display modes.
Actually of course texans are no dumber or smarter than anyone else, but there were very many opportunities for a laugh, parallel to the "known to the state of California to be harmful" signs. Still, it would be interesting to see if there are cultural differences before drawing too broad a conclusion.
It's so easy to find videos of this online. People should know better but hubris is a hell of a drug. Anyway, I doubt the signs help much.
Always interesting in the wet season. https://www.youtube.com/watch?v=S3zPIbaE_nI
Far better to restructure the environment so that the person can get the work done. In the case of traffic deaths we have really good data that says that you should change the structure of streets and roads so that people instinctively drive safely.
2] when some one shifts focus to do something, and is nagged to do exactly that thing, the chance of it being done, with quality, or at all, will approach zero.
I was bummed when they capped the reading at 70 on the signs in the I-5 mountain passes in Oregon, but that's Oregon for you, I guess. At least they let you pump your own gas now.
Edit: Changed the last paragraph to apply it to traffic.
In Texas they throw up the message similar to "1669 deaths this year on Texas roads" as in the article. Drivers who read the sign have no way of knowing whether this is lower than, higher than, or about the same as the number of deaths for that date in previous years. As the year goes by the number gets larger but there is still no context.
A better way to convey this information if you are going to do it at all would be use a reward/penalty message format that is readily understandable at highway speeds.
The message should be simple. For example - "Texas Traffic Fatalities lower this year than last. Good Job! Drive Friendly" or "Texas Traffic Fatalities higher this year than last. Drive Friendly"
That tells anyone reading exactly what they need to know and the message highlighting an improvement contains a simple reward message. When drivers become accustomed to seeing the message in this format they will immediately recognize that fatalities must be higher because the reward is missing from the message. That could trigger an effort to drive more safely.
Personally I hate the DMS signs and billboards. In a world where I made the rules there would be no billboards at all as the immortal Ogden Nash said:
I think that I shall never see a billboard lovely as a tree.
Perhaps, unless the billboards fall, I'll never see a tree at all. -- Ogden Nash (after Joyce Kilmer's poem about trees)
I would not allow any form of dynamic advertising along roads or highways. That means that if billboards are allowed there would be no LED billboards flashing a new message periodically and distracting drivers. All allowed billboards would be totally static and unless they advertised critical services for travelers they would be unlit at night. That means that no lighted billboards unless they are advertising travel-related infrastructure such as restaurants, clean restroom facilities available for travelers, auto towing, maintenance, or repair shops, etc. All advertised infrastructure can only be lighted during the hours when it is open and available for use by travelers. If the business is closed then the lights must be off.
There are already too many distractions for drivers with dash-mounted tablets, cell phone holders, navigation screens, and drivers do not need flashing shit along the road to distract them from the important task of maintaining a safe following distance from other traffic and monitoring other drivers on the road while scanning the highway for hazards along their route like traffic light status, objects in the roadway, unsecured loads, etc.
> That tells anyone reading exactly what they need to know and the message highlighting an improvement contains a simple reward message
Do they need to know it though? Is someone going to see that, and adjust what they're doing because numbers are trending up? It seems unlikely.
If you have to show something, how about a standard caution sign that says "elevated accident zone"? It conveys everything that /might/ be helpful, is highly relevant to the specific area the driver is in, and does not require critical thinking (numbers up? numbers down? how does this affect me? Is it for this spot, or all of Texas?). Caution signs are also taught as part of driver's ed as warning of road hazards - deer crossing, falling rocks, etc.
The data cited shows that the negative message they currently employ has an effect on the accident rate: multi-vehicle accidents increase in proximity to the signs.
This suggest that some drivers see the message and react by adjusting their driving and that other drivers near them either do not see the sign, do not make adjustments, or are not paying enough attention to the road to notice that a driver in their hazard zone has made an adjustment that will cause an accident if they don't react similarly.
It may be that some drivers see the sign and slow down or change lanes to a slower traffic lane while the driver behind them is too close and this speed or lane change leads to a collision.
Using the signs to highlight sections of highway with higher than average accident rates sounds like a good idea. It would be especially useful on interstates affected by sudden heavy rainfall where ponding leads to hydroplaning at ordinary safe speeds for a dry highway. There is a long stretch of interstate west of FtWorth where this is a problem due to the number of curves and the crown of the road not allowing rain to flow to the shoulders fast enough to prevent ponding.
While it is true that caution signs and things like this are part of driver's ed, that doesn't mean that they make it into the actual practice part of every driver's skillsets. In my view, everyone should be required to take a defensive driving test at least every 5 years so that the lessons about focusing on driving and minimizing accident potential are set in stone. Ordinary drivers ed covers this ground but most drivers never have to revisit the safe driving habits after getting licensed unless their employer requires defensive driving or they get a ticket and opt for ticket dismissal thru defensive driving course.
This is all potentially true, but an equally valid interpretation of the limited data is that the larger sign requires more cognitive overhead, resulting in less attention given to the road.
> take a defensive driving test at least every 5 years so that the lessons
Yes, especially here in the US where it's really easy to get a license to drive. A cultural shift would help too, because right now it's all about "Well, it's not my fault" - as if the accident and potential fallout is less important than who bears financial responsibility. In /most/ cases, there are defensive steps a driver could have taken to avoid an accident even if they were not directly at fault, but we don't emphasize that enough. (Or at all?)
Whoever they have picking messages is doing a really good job keeping things consistently corny.
Around here, the signs flip between time and distance to other highways or cities and a safety message. If there is an accident closing lanes, that's displayed instead of the safety message. The signs seem okay at night. Nothing like blinding billboards.
I think the message has a more positive impact if it emphasizes positive things or uses humor. Texas, with their focus on depressing stats with no context, loses out by alienating drivers.
Anyway fellow Texan, I too appreciate the traffic data the most. Just tell me before I get to my exit whether I should consider a different route due to traffic or unusual events. Provide actionable information and stop all the dumbass silver warnings and missing person shit unless it can clearly be demonstrated that those warnings have helped locate a missing person or an old person who just needed to get away.
It's worth a try.
Like telling someone they will do badly on a test and comparing them with a control group that isn't told that. Reverse placebo effect.
No clue if that's true, but it doesn't seem entirely unlikely so my thumbs don't go inside the wheel.
Showing relevant information with a clear impact on the driver has proven to work effectively: have color-coded feedback telling you that your insurance premium just went up when you drive too fast, erratically, too close to the car in front don’t look ahead, or turn without checking behind the mirrors and behind you.
Accepting this reality, and working with it, is completely different from "mass mind control". Any time a city decides which streets to repair, it's a nudge. Any time a city decides which streets to renovate at the same time, it's another nudge. Any time a city decides not to repair streets it's a nudge. How do you get out of this "nudge-less"?
how about you fix the streets when people complain that the street in front of their house is fucked? or better yet stop promising people you can fix their streets if they continue to pay their taxes and stop arresting people who fix their own streets? what are you even talking about lol
I've made a clear point in my previous comment. Please engage with it directly.
Maybe you're not aware, but the thing about mother birds rejecting their chicks if they're touched by humans was a nudge. Not like an exaggeration or a miscommunication. A straight-up nudge. You literally funded your own scientific gaslighting hahaha.
Maybe that's not consequential enough for you. The thing about masks not working was a nudge so you wouldn't buy up all the masks. Then the thing about masks stopping the spread was a nudge. You got cross-nudged on the same issue by the same guy. And that doesn't even get into what people were told about medicine these last few years.
Go ahead and defend your ludicrous utilitarianism where you can monitor and track and account for all possible consequences of your publicly-funded disinformation via your surveillance state.
What of the people who die because your deliberate falsehoods? Do they get restitution? Or they're just collateral damage on the avenue to utopia?
Thank you for being upfront with this, I'll end the conversation here. You've either fundamentally misunderstood my point or are arguing in the worst faith possible. Either way it doesn't make sense to talk any further. Have a nice day!
The 55 MPH Speed Limit Will Be Enforced
If I get a speeding ticket, can I just argue that the sign's use of the future tense clearly indicates the lowered speed limit doesn't apply yet?
That's why I formulated my silly example the way I did, but I guess I was being too subtle.
And generally don't those say "Strictly Enforced"? The implication being that they will bust you even for 56 in a 55 (generally, again, because it's a construction zone).
Finally, I seem to remember that the issue is that California has a relatively (couple years old) new law that a speed limit must demonstrate that it is at the 80% point or has an explicitly documented exception or it's challengable. Presumably, these signs fall into the "explicitly documented exception" category.