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Hard-braking events as indicators of road segment crash risk

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Re: Hard-braking events as indicators of road segment crash risk

#21

Post by grog454 »

avidiax wrote: post #9
pavel_lishin wrote: post #4

Earlier quoted context omitted.

My mom had a device installed in her car to get a discount on her insurance, and she was always upset at the hard braking thing - whenever she did it, it was because another car was doing something unsafe that she couldn't control, like pulling out in front of her.

Some amount of that is inevitable, but there is another level of defensive driving where you anticipate poor behavior and arrange that it won't cause an accident. 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…

The landing page video's first incident is a car coming from behind and from the right, cutting off the filming car. The filming car didn't react at all when instant (but measured) braking would've been safer to start building a distance buffer.

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.

Re: Hard-braking events as indicators of road segment crash risk

#22

Post by garaetjjte »

kube-system wrote: post #10
pavel_lishin wrote: post #4

Earlier quoted context omitted.

My mom had a device installed in her car to get a discount on her insurance, and she was always upset at the hard braking thing - whenever she did it, it was because another car was doing something unsafe that she couldn't control, like pulling out in front of her.

Drivers often believe that their insurance rates should be based solely on whether they follow driving rules, but the risks to insurance are not isolated to this. Someone can follow every rule perfectly, but if they are involved in an accident they incur costs for their insurance company.

If they are not found at fault then indeed there's no cost for their insurance company?

Re: Hard-braking events as indicators of road segment crash risk

#23

Post by bluGill »

kube-system wrote: post #6
harshaw wrote: post #2

Nice research. This is fairly well known in insurance circles. Most auto insurers that do telematics consider hard braking the strongest indicator of risk. One of the things that we do at work (Cambridge Mobile Telematics) is build tools to deal with this risk. We have apps that monitor driving and we play a tone to indicate that a hard braking event was detected. Simply letting people know that they had a hard braki…

> Simply letting people know that they had a hard braking event is an effective mechanism for behavior change 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.

Does it matter why? The important part is getting people to change behavior.

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.

Re: Hard-braking events as indicators of road segment crash risk

#24

Post by xnx »

presidentender wrote: post #20

I got one of those dongles from my insurance company that plugged into the ODB2 port and reported my driving habits. 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 goo…

Thanks for sharing. I'm genuinely impressed to hear someone publicly share a story of growing self awareness and improvement.

Re: Hard-braking events as indicators of road segment crash risk

#25

Post by toast0 »

alwa wrote: post #17
harshaw wrote: post #2

Nice research. This is fairly well known in insurance circles. Most auto insurers that do telematics consider hard braking the strongest indicator of risk. One of the things that we do at work (Cambridge Mobile Telematics) is build tools to deal with this risk. We have apps that monitor driving and we play a tone to indicate that a hard braking event was detected. Simply letting people know that they had a hard braki…

When you modify their braking behavior, is that enough to improve their overall driving behavior? Or do forward collisions and rear-enders make up substantially all of what the driver can control, so training the behaviors to reduce that type of near-miss reduces the driver's overall crash risk? To the point that it's similar to the safest tranche? Is it that hard braking events are broadly indicative of surprises of…

Regardless of everything else, forward collisions are most likely to have the driver considered at-fault. Seems like reducing those in your insured population would reduce covered losses more than reducing collisions where your insured may not be at fault.

Re: Hard-braking events as indicators of road segment crash risk

#26

Post by sigseg1v »

avidiax wrote: post #9
pavel_lishin wrote: post #4

Earlier quoted context omitted.

My mom had a device installed in her car to get a discount on her insurance, and she was always upset at the hard braking thing - whenever she did it, it was because another car was doing something unsafe that she couldn't control, like pulling out in front of her.

Some amount of that is inevitable, but there is another level of defensive driving where you anticipate poor behavior and arrange that it won't cause an accident. 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…

Adding on to this, a common reaction I see to online videos of driving incidents is "why did this person just stop? of course you are going to crash into them. They shouldn't have stopped" and many people agreeing with it. It seems they are blind to the fact that if the following driver was using a safe following distance and speed, they should easily be able to stop, making the incident the fault of the driver following too close, not the one stopping.

Re: Hard-braking events as indicators of road segment crash risk

#27

Post by thomasguide »

avidiax wrote: post #9
pavel_lishin wrote: post #4

Earlier quoted context omitted.

My mom had a device installed in her car to get a discount on her insurance, and she was always upset at the hard braking thing - whenever she did it, it was because another car was doing something unsafe that she couldn't control, like pulling out in front of her.

Some amount of that is inevitable, but there is another level of defensive driving where you anticipate poor behavior and arrange that it won't cause an accident. 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…

Without wanting to paint with too broad a brush, I would say in my experience driving in 10x countries, U.S. drivers, being most habituated to spending their lives in cars, drive in the most distracted, least careful way. Especially in places where the typology is the U.S. default of low-density, car-oriented sprawl. Accordingly there are an appaling number of deaths and injuries on the road: 1 in 43,750 people dies each year in the U.K. in automobile accidents vs. 1 in 8,500 in the U.S.A.

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.

Re: Hard-braking events as indicators of road segment crash risk

#28

Post by Someone1234 »

This type of research is highly valuable but too rare; this is generally because of how we view Road Accidents at a core level:

- 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.

Re: Hard-braking events as indicators of road segment crash risk

#29

Post by WarmWash »

pavel_lishin wrote: post #4
harshaw wrote: post #2

Nice research. This is fairly well known in insurance circles. Most auto insurers that do telematics consider hard braking the strongest indicator of risk. One of the things that we do at work (Cambridge Mobile Telematics) is build tools to deal with this risk. We have apps that monitor driving and we play a tone to indicate that a hard braking event was detected. Simply letting people know that they had a hard braki…

My mom had a device installed in her car to get a discount on her insurance, and she was always upset at the hard braking thing - whenever she did it, it was because another car was doing something unsafe that she couldn't control, like pulling out in front of her.

If you take a seasoned motorcycle rider and put them in one of those dashcam subs, they'll rip their hair out.

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.

Re: Hard-braking events as indicators of road segment crash risk

#30

Post by RupertSalt »

WarmWash wrote: post #29
pavel_lishin wrote: post #4

Earlier quoted context omitted.

My mom had a device installed in her car to get a discount on her insurance, and she was always upset at the hard braking thing - whenever she did it, it was because another car was doing something unsafe that she couldn't control, like pulling out in front of her.

If you take a seasoned motorcycle rider and put them in one of those dashcam subs, they'll rip their hair out. 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.

A seasoned motorcycle rider should be unable to rip out any hair, due to safely wearing a helmet!
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