This research team used Google's first-party location data to identify San Jose's Interstate 880/US 101 interchange as a site with statistically extreme amounts of hard braking by Android Auto users.
But you don't need machine learning to know that... San Jose Mercury News readers voted that exact location as the worst interchange in the entire Bay Area in a 2018 reader poll [1]
It's not a lack of knowledge by Caltrans or Santa Clara County's congestion management agency that is keeping that interchange as-is. Rather, it's the physical constraints of a nearby airport (so no room for flyovers), a nearby river (so probably no tunneling), and surrounding private landowners and train tracks.
Leaving aside the specifics of the 880/101 interchange, the Google blog post suggests that they'll use this worst-case scenario on a limited access freeway to inform their future machine-learning analyses of other roads around the country, including ones where presumably there are also pedestrians and cyclists.
No doubt some state departments of transportation will line up to buy these new "insights" from Google (forgetting that they actually already buy similar products from TomTom, Inrix, StreetLight, et al.) [2]
While I genuinely see the value in data-informed decision making for transportation and urban planning, it's not a lack of data that's causing problems at this particular freeway intersection. This blog post is an underbaked advertisement.
[1] https://www.mercurynews.com/2018/04/13/101-880-ranks-as-bay-...
[2] https://www.tomtom.com/products/traffic-stats/ https://inrix.com/products/ai-traffic/ https://www.streetlightdata.com/traffic-planning/
Google/Apple probably collect a massively larger amount of data than those other companies, putting those other companies at a risk of losing future revenue.
Between Google and Apple pretty much every car in the US is monitored.
Where Google/Apple's coverage is quite valuable is for near-real-time speeds for atypical events -- say like yesterday's Super Bowl. But that's not what this blog post is about -- this post is about a well-established pattern that can be identified with historical datasets.
All that to say that vendors sell a wide variety of data products to transportation planners, but just because Google is now entering this niche market doesn't mean they'll be "the best" or even realize what their strengths are.
"A 1974 study by Hall and Dickinson showed that speed differences contributed to crashes, primarily rear end and lane change collisions"
Hall, J. W. and L. V. Dickinson. An Operational Evaluation of Truck Speeds on Interstate Highways, Department of Civil Engineering, University of Maryland, February, 1974.
if we could bridge that gap, the economic incentive for municipalities would be massive lower accident rates mean less property damage and fewer expensive liability lawsuits for the city. it's basically a potential safety feedback loop that just needs the right data sharing protocol to actually kick in.
I was a bad driver. It would frequently beep at me to let me know that I had braked too hard. I was mystified. "What should I have done differently," I'd think, as I raged at the objective machine that judged me so.
The next time my brother came to visit, he called mom. "Oh, and presidentender is a good driver now." I didn't put the pieces together right away, but it turned out that the dongle had actually trained me, like a dog's shock collar.
The reason for my too-frequent hard-braking events wasn't speed, although that would be a contributing factor. It was a lack of appropriate following distance. Because I'd follow the drivers in front of me too closely I'd have to brake hard if they did... Or if they drive normally and happened to have a turn coming up.
Over the period I had the insurance spy box in my truck I learned without thinking about it to increase my following distance, which meant that riding with me as a passenger was more comfortable and it beeped less often. Of course since I'd been so naughty early during the evaluation they didn't decrease my rates, but I think the training probably did make me statistically less likely to crash.
This always stuck with me
It's probably the best single thing anyone can do to improve safety. It also reduces wear-and-tear on your car, and increases your fuel economy as a side benefit.
Why hasn't gamification of safe driving habits been built directly into the car itself before now?
I think it will also back down the cruise control (if set) if it detects that you are gaining on the car ahead. That might be MILs Toyota though.
I learned the "two second rule" in Driver's Education 45 years ago and generally follow that. Nothing more annoying than having the car behind you riding your bumper.
I am so glad it hasn't. Data point of one, but gamification now has the opposite effect on me: it's such a well-worn pattern that it just annoys me. It was great when it was novel. I wonder how many others feel the same but without sampling it's hard to know.
I also think some of the car sensors (Subaru especially) that are trying to make you safer are notoriously bad.
I also find the random “coffee break” notice on Subarus frustrating.
My personal examples: “eyes on the road” - triggered frequently by one pair of sunglasses I have, looking left to check blind spot, checking mirrors, etc.
“Hands on the steering wheel” - triggered occasionally on long drives when I have been giving input, but very light input.
Now she still has the machine, still follows too closely, and still breaks too hard in her new car...
Good it worked for you though!
No smooth maintaining of speed and nice passes as able without slowing down.
Surprisingly, his accidents have mostly seemed to involve gas pumps, barriers, and other obstacles at low speed.
Incredibly frustrating, and I've driven all over North America - there's practically no major city where this doesn't happen. If you're not maintaining a safe following distance on city/residential streets, that's a different matter.
Unfortunately, sometimes over a 45 minute freeway commute, dropping back repeatedly means arriving 15 minutes or more later. Again, no big deal now, but it was somehow unacceptable when I was younger.
A slight increase in average speed really only makes a significant difference over long drives. (5 mph increase over a 10 hour drive can cut off 50 minutes).
Otherwise we are talking about small differences in efficiency.
(I would be very open to another opinion here.).
My opinions are formed by nearly ~2 million miles driven at this point, two different driving courses, and the motorcycle safety course.
One thing I truly think that’s overlooked is how reduced road noise in the vehicle cabin can both reduce driver fatigue, but also frustration in traffic.
You can't really say that without knowing the starting speed, or alternatively the distance. All you can say is that a 5 mph increase over a 10 hour drive with get you 50 miles farther.
If you do a comparison of a 600 mile trip at 60 vs 55 you’re pretty close.
But yes, to be pedantic and more exact, you are spot on that it will get you 50 miles closer.
But in real world examples,
If you’re traveling 700 miles.
65 vs 70, 70 will reduce your time by 43 minutes.
So in certain scenarios, 5 mph difference must be able to save you 50 minutes ! ;)
(I do understand your point, and you’re correct. I’m just poking fun at it- my point with the mph difference is because 50 miles doesn’t have the same translation for most people at 50 minutes, but is a more accurate data approach. )
1. In any amount of traffic above “a few cars” people will cut in front of me, sometimes two, negating the safe following distance. Regardless of speed.
2. If I have a safe following distance while waiting for someone to get over. (I e they’re going 60, I want to go 70), if I have my distance set at a safe following distance, people are much more likely to weave / pass on the right. (My theory would be that the distance I’m behind the person in front of them signals that I’m not going to accelerate / pass when the person gets over ).
Disclaimer: I don’t usually have to drive in any significant traffic, and when I do (Philly, New York City), I’m probably less likely to use the automatic features because the appropriate follow distance seems to increase the rage of drivers around me.
However - I will say most of the roads I’m on are 2 lanes of traffic. I will have to experiment and see if this doesn’t occur when there are 3 or 4 lanes.
What I will say is some of this may be the difference between manual driving - and automatic.
If I’m manually driving - where my follow distance fluctuates more due to speed / traffic - almost no one cuts in.
If I am driving where I’m using the vehicle to maintain a perfect set distance, people cut in.
Again, anecdotal
At any rate, even if people are continuously going around you like water going around a rock in a stream, you only have to drive 2 mph slower than traffic to constantly rebuild your following distance from the infinite stream of cutoffs. But my experience is the majority of following distance is eaten up by people randomly slowing down, not cutting in.
The issue is not that I can’t rebuild the following distance, the point I’m trying to make is that even if I constantly rebuild the following distance it sets off a cascading effect.
I’m following at set speed, car cuts in front, hits brakes, I now slow down, car behind me slows down, I rebuild following distance and car perhaps 7-8-9 cars behind me repeats because at some point the cascade magnifies to a larger slowdown behind.
Can I mitigate this by manually letting my distance be closer for a time, and slowly easing to larger ? Yes.
But if I allow the car to do it automatically, it will increase the follow distance at a rate that causes a cascade in tight traffic.
Though - I do think with these discussions on HN- it does depend on where you’re driving.
My experiences are centered on East Coast, thinking of route 80, 81, 83, etc. or Philly / New York City.
The driving experience is radically different in California, Florida , or the mid west.
I would say when driving in California people seem to navigate traffic better. (SF, LA) then on drivers on 80/81/83. (Or perhaps it’s due to better designed roads ).
On the occasion when I am towing our travel trailer, it is really incredible how unsafe that makes other drivers act around me. They will jam themselves in front of me at all costs, with no consideration for physics.
Just a few of these was enough that my "discount" was only a few dollars. I regret giving Progressive my driving data.
- Road Accidents: "A driver caused this, let's determine who, and find them at fault."
- With Air Accidents: "The system caused this, let's determine which elements came together that ultimately lead to this event."
The first is essentially simplifying a complex series of events into something black and white. Easy to digest. We'll then keep doing it over and over again because we never changed the circumstances.
The second approach is holistic, for example even if the pilot made a mistake, why did they make a mistake, and what can we do to prevent that mistake (e.g. training, culture, etc)? But maybe other elements also played a part like mechanical, software, airport lightning, communications, etc.
I bet everyone reading this knows of a road near them that is an accident hotspot and I bet they can explain WHY it is. I certainly do/can, and I see cops with crashed cars there on a weekly basis. Zero changes have been made to the conditions.
In a similar way that Google Maps shows eco routes, it’d be fun for them to show “safest” routes which avoid areas with common crashes. (Not always possible, but valuable knowledge when it is.)
harshaw•2h ago
pavel_lishin•1h ago
avidiax•1h ago
Have a look at a few dash cam accident videos [1]. There are many maladaptive patterns of behavior, but a frequent one that the average good driver can improve on is limiting speed on two occasions: when approaching a blind spot, and when passing stopped or slow traffic.
That second one gets lots of otherwise good drivers. They seem to think that by limiting their speed vs slow/stopped traffic they'd be encouraging people to dart in front of them. Which is somewhat true. But with limited speed, that's an avoidable or less injurious accident. By gunning it past stopped traffic, you make the accident unavoidable and more serious.
[1] https://www.youtube.com/@IdiotsInCars1
grog454•1h ago
One thing HPDE taught me is that most people under brake in dangerous situations because they simply don't know the limit of their vehicle nor the sensitivity range of the brake pedal.
The hard braking heuristic makes sense when estimating risk of road segments, but not as a proxy for driver competence.
ominous_prime•1h ago
35 years without an accident on my record isn't because I'm a magnificent driver, it's because I always try to leave a way out for when something unexpected happens, because the unexpected _does_ happen.
The fact that some people may have the skill to drive more aggressively means nothing in the aggregate as far as insurance companies are concerned. If you are skilled enough to drive in that manner, you are skilled enough to avoid it as well. It's simply statistics.
grog454•30m ago
Then use it? Mandate reaction speed tests or other driving mechanics competency evaluation (not road sign comprehension) and watch insurance margins explode.
The driver in my example did poorly and scored top marks in the heuristic.
sigseg1v•1h ago
duderific•1h ago
SoftTalker•1h ago
infecto•1h ago
thomasguide•1h ago
Inb4 deaths per mile driven, I'd argue higher VMT in the U.S.A. only proves the point - too many cars being driven too much because of silly land use. High VMT is acutally a symptom of a dangerous mobility system as much as a cause.
maest•1h ago
geocrasher•54m ago
But now even when in a car, I retain that "I'm invisible" mentality, which makes me much more aware of what other drivers are doing, and much more skeptical of their ability to make good decisions. This has saved me several times.
kube-system•1h ago
garaetjjte•1h ago
AngryData•1h ago
amanaplanacanal•1h ago
SoftTalker•1h ago
kube-system•23m ago
First, the insurance company incurs costs just processing the claim. If things escalate with the other party, they may even incur legal and court costs.
Additionally, there are some costs that are incurred regardless of fault -- like personal injury protection.
Even defining "who was at fault" is a complicated situation. A lot of people presume that it is as simple as: whoever the police issues a citation to at the scene is 100% at fault. But that's not the way things actually work. The way liability is assigned depends on the state, but in a comparative negligence state you could be proportionately liable for as little as one percent of the fault of the accident. Maybe someone else ran a red light, you entered the intersection on green, and hit them. You could end up sharing some of the cost for that, if it is found that you could have avoided the accident but decided not to.
And even after all of this, if the other party runs out of money, doesn't have insurance, or runs away at the scene, your insurance company is stuck paying the costs under their uninsured/underinsurred motorist coverage.
infecto•1h ago
It’s this obnoxious audio warning that tells me I had a hard breaking and it’s 9/10 because I stopped at a red light that I would not have made on yellow. And then it sends me tips and reminders about reducing hard breaking events and it’s annoying. I know they have done the analysis but it detects moderate hard breaking which is frustrating. One of those things that I am sure in net is positive but perhaps slices of the population it does not benefit.
amanaplanacanal•1h ago
infecto•1h ago
WarmWash•1h ago
Most people have near zero defensive driving skill, and view someone pulling out in front of them as "nothing I could have done", when the dashcam shows the offending driver showed 5 signs of pulling out ages before the accident occurred.
RupertSalt•1h ago
organsnyder•1h ago
doubled112•1h ago
Much of being a good driver is just awareness.
One time my light turns green, I don't go. As my wife asks what I'm waiting for, a pickup blows the light. We weren't the first car at that light, and years later she still talks about how there's no way I could know. Well, I didn't get us t-boned at 80 so I must have done something right.
dghlsakjg•18m ago
I do both and I am constantly surprised at the lack of situational awareness of drivers when I’m a passenger in their cars.
I think truckers probably get the same thing too.
kube-system•1h ago
Has this been studied in isolation? Many of the tools that notify upon hard braking also are used to impose financial penalties for doing so... I suspect people may be reacting to the financial incentives.
timbaboon•1h ago
bluGill•1h ago
of course if they change such that they don't break hard when needed that is bad, but if the change such that they don't need to break hard in the first place because they slow down in places that are dangerious that is the point.
kube-system•18m ago
Yeah, if you want to do that, it would be helpful to know whether a financial incentive is required for the effect or not.
dghlsakjg•14m ago
There is a minor financial aspect (price of fuel), but I’m far more interested in seeing if I can get a better “green score” at the end of the drive.
zahlman•1h ago
... How do people not notice that they are braking hard?
infecto•1h ago
advisedwang•1h ago
alex43578•1h ago
The cause of hard braking isn’t mutually exclusive: bad driving or bad road design.
jstanley•5m ago
rogerrogerr•1h ago
mschuster91•39m ago
Fuck all of that.
Sharlin•1h ago
yial•51m ago
Example: open space on either side of the road, tends to encourage people to drive faster.
Closing that space (whether by buildings, shrubbery, etc ) will slow the speed.
But I will say there are also “obvious” bad designs - the rare far to short on ramp to merge, where drivers don’t understand how to adjust.
Or the one I most frequently encounter are “blind spots” created by the speed of an intersecting road, where a mirror may be attached to a pole / tree, or a sign reminding people to look left right left, or even instructing where cars should be beyond for a safe pull out.
I know of one intersection near me that both has markers on the road(don’t pull out if cars are at or beyond this marker), and a reminder about looking, but still has a high frequency of accidents.
buckle8017•37m ago
alwa•1h ago
Is it that hard braking events are broadly indicative of surprises of lots of sorts, and so it happens that the only way to eliminate them all is to develop a full range of defensive driving habits?
More Goodhart's Law or Serenity Prayer?
toast0•1h ago
munificent•1h ago
mecsred•1h ago
infecto•1h ago
It’s still out of the norm braking for my style of driver but from what I see on the road, people drive aggressively like this. Especially in the US.
dghlsakjg•12m ago