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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

#271

Post by whackernews »

sagarm wrote: post #95
mountain_peak wrote: post #46

Earlier quoted context omitted.

Maintaining a safe following distance is incredibly challenging on busy freeways where hard braking is often 'required'. Most people have likely found themselves in this situation: vehicle changes lanes in front of you; you slow down to maintain a safe following distance, another car sees a gap and changes lanes in front of you. Repeat for your entire commute. Incredibly frustrating, and I've driven all over North Am…

If you think highway driving requires hard braking, you're a bad driver.

Absolutely agree. I take it a step (probably too far) further and think if you’re breaking on the motorway at all, you’re a bad driver. Ok, sometimes you have to, it’s chaotic out there, I get it. If you’re paying attention to actually driving your two ton killing machine you can drive for 200 miles on a motorway and not touch the break once.

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

#272

Post by genocidicbunny »

Sohcahtoa82 wrote: post #252
c22 wrote: post #240

Earlier quoted context omitted.

It seems like a tragedy, but actually it can be a boon as long as you travel in neither the leftmost nor rightmost lane . The majority of the traffic entering your buffer will be exiting your buffer out the other side as soon as they can, so you can just chug along at a (greatly reduced, but) consistent speed. Meanwhile, the traffic to either side of you is in standstill, paralyzed by your bow wake.

It's wild to me how often the left lane is not the fastest lane. I've had times where the right lane ends up being the fastest. On I-5 near Woodburn, OR, it's 3 lanes. So many drivers, including truckers, will often stay out of the right lane entirely to avoid being caught up in traffic coming on/off. Meanwhile, the left lane is going 5 mph under the limit because there's a left-lane camper somewhere miles ahead. So…

Truckers sometimes have a good reason to do that -- they can't brake or accelerate as quickly as a small vehicle, and thus can end up going very slowly if they stick with the right lane. To a driver going 3 exits down the 205 it's not a big deal, to a truck driver doing the same they may be at the end of a long haul up the I5 and every minute starts to count since it can affect their pay. And if you can avoid hard braking/hard acceleration in the right lane, that can help your fuel costs quite a bit since slowly coasting behind someone doing 5 under in the left lane is more efficient than jerking around in the right lane.

There are plenty of ramps on I5 and 205 that I merge to the left for because I know they will spill into the right and (when it exists) middle lanes. Because of how traffic also reacts to brake lights (some people brake too hard even when they have sufficient distance to let off the gas and coast to a slower speed) it seems like it ends up making my experience through those stretches a bit better.

Ultimately, any individual behaviour is largely irrelevant, it's what the whole mass of cars moving along does that affects things the most. Often you don't want to be the (significantly) odd one out regardless of the situation.

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

#273

Post by colechristensen »

_carbyau_ wrote: post #241
radlad wrote: post #101

Earlier quoted context omitted.

On the other hand, at age 20, with very high premiums, I got one of these devices which never beeped except on a few too-short exit ramps on highways in my city. The choice on these exits is to slow down traffic on the highway, or endure a "hard stop" by braking immediately when you are on the ramp, and coming to a full stop at the stop sign. Just a few of these was enough that my "discount" was only a few dollars. I…

There is no upside to giving personal data to a for-profit company with a monolithic amount of money and a clear view of the statistics around any activity. The incentives just don't line up.

I'm fine with having opted in to doing it for 30 days once.

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

#274

Post by rootusrootus »

Sohcahtoa82 wrote: post #252
c22 wrote: post #240

Earlier quoted context omitted.

It seems like a tragedy, but actually it can be a boon as long as you travel in neither the leftmost nor rightmost lane . The majority of the traffic entering your buffer will be exiting your buffer out the other side as soon as they can, so you can just chug along at a (greatly reduced, but) consistent speed. Meanwhile, the traffic to either side of you is in standstill, paralyzed by your bow wake.

It's wild to me how often the left lane is not the fastest lane. I've had times where the right lane ends up being the fastest. On I-5 near Woodburn, OR, it's 3 lanes. So many drivers, including truckers, will often stay out of the right lane entirely to avoid being caught up in traffic coming on/off. Meanwhile, the left lane is going 5 mph under the limit because there's a left-lane camper somewhere miles ahead. So…

> On I-5 near Woodburn, OR

The section of I-5 between Portland and Salem is absolutely psychotic, and I have never been able to reason out exactly why. It consistently has a left lane jammed with angry people going at or below the speed limit, a fairly normal center lane filled with cruisers, and a mostly empty right lane with the occasional big rig and regular very-high-speed cars expressing their frustration with the left lane by going 25+ mph over the limit in the right lane.

I know that's what you basically just said. Just venting. The driver behavior in that section of freeway confounds me, and I do not know what the underlying cause is. It is otherwise an unremarkable bit of interstate like any other.

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

#275

Post by genocidicbunny »

a_e_k wrote: post #235
maerF0x0 wrote: post #219

Earlier quoted context omitted.

It's frustrating because someone is taking your safety buffer as their opportunity to travel faster. And it results in you having to travel slower and slower to maintain the gap that is constantly consumed, tragedy of the commons style, by opportunists.

Not to mention if that if somebody needs to come over, the proper thing to do is signal first . Then I'm happy to politely ease off a bit and open more space for them to come over safely. It's the people who aggressively slide right over just a few feet in front of me (cutting off nearly all of my safety buffer) without so much as a signal that really drive me nuts.

Unless I'm the last car in a line and there's plenty of open space behind me. Then you should just wait until after I've passed before merging, because otherwise you create a little ripple in the flow. A few ripples and you got a wave, and that's how you get traffic.

So for the love of gods, if you're merging, even if you signal, match speeds for merging. If you're too slow to match speed, then suck it up buttercup, and hang out in the right lane until there's an opening.

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

#277

Post by rootusrootus »

c22 wrote: post #240
maerF0x0 wrote: post #219

Earlier quoted context omitted.

It's frustrating because someone is taking your safety buffer as their opportunity to travel faster. And it results in you having to travel slower and slower to maintain the gap that is constantly consumed, tragedy of the commons style, by opportunists.

It seems like a tragedy, but actually it can be a boon as long as you travel in neither the leftmost nor rightmost lane . The majority of the traffic entering your buffer will be exiting your buffer out the other side as soon as they can, so you can just chug along at a (greatly reduced, but) consistent speed. Meanwhile, the traffic to either side of you is in standstill, paralyzed by your bow wake.

> as long as you travel in neither the leftmost nor rightmost lane

What I really hate, however, is that plenty of people will cruise in the center lane but still not leave a decent gap between them and the car in front. They effectively turn a three lane freeway into two one-lane freeways by hobbling the ability of anyone else to switch lanes. The freeway moves way smoother when there is a modest, predictable speed differential between each lane so that people can find their way into the next lane over without having to force the issue.

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

#278

Post by genocidicbunny »

maerF0x0 wrote: post #267
a_e_k wrote: post #235

Earlier quoted context omitted.

Not to mention if that if somebody needs to come over, the proper thing to do is signal first . Then I'm happy to politely ease off a bit and open more space for them to come over safely. It's the people who aggressively slide right over just a few feet in front of me (cutting off nearly all of my safety buffer) without so much as a signal that really drive me nuts.

It's the people who hit the gas when they see your signal, that really irk me. In Austin I stopped signaling because it was a punished behavior.

My experience driving in MA and NY was similar, but so often it was because a rusted out shitbox was trying to merge in that would slow down traffic significantly, and not only put me at risk of rear ending them, but being rear ended myself.

When flows merge, there's turbulence. There's less turbulence if the flows are more closely matched, including speed.

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

#279

Post by genocidicbunny »

aeontech wrote: post #230
Sohcahtoa82 wrote: post #213

Earlier quoted context omitted.

> vehicle changes lanes in front of you; I will never understand why this is so rage-inducing for people. Changing lanes is a necessary part of navigating, even during busy traffic. People on an on-ramp will need to get in front of somebody . People needing to move back to the right because their exist is coming up will need to get in front of somebody . Your lane is not a birth right. Let people merge. > you slow do…

I'll tell you what I specifically and intentionally do when I need to change lanes. I brake slightly, signal, and wait for the person on my right or my left to pull ahead of me, then change lanes immediately _behind_ them. Then sit there for a moment until my following distance evens out a bit. This ensures that a) I do not cut anyone off accidentally, and minimize the amount of stress in my immediate part of the uni…

You shouldn't be braking when changing lanes is what I was taught, you should be matching the speed of the lane you're merging to. There are many drivers who think that braking is always the right solution, when sometimes it's a little more gas.

And in inclement conditions, it can make the difference between losing control of your vehicle or not. When you brake, you decrease your steering ability in most cars. Fine when its calm and sunny in CA, not so much when it's icing over near Ashland OR on the pass.

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

#280

Post by rootusrootus »

rconti wrote: post #169

This is a great use of this technology. In aggregate, these hard braking events _do_ tell us about road design issues. They also tell us about problematic drivers, in aggregate. I'll never use one of these dongles, though, because I don't want my every move second-guessed. There's nothing _inherently_ dangerous about isolated hard braking or cornering or acceleration events. It all depends on context. Am I braking ha…

> There's nothing _inherently_ dangerous about isolated hard braking or cornering or acceleration events.

I have to hope that the actuaries at the insurance company are well aware of that. Tuned correctly, the algorithm should not unfairly penalize you.

I am reminded of my mother-in-law. She has very few at fault accidents in her decades of driving. And yet she has been involved in a statistically unlikely number of major wrecks. She would say that she is a safe driver, because she is not found at fault. I think it more likely that she is an unsafe driver who creates situations where accidents are more likely to occur but in a way that will not peg her as the underlying cause. Her rates should go up. As should yours, if you are experiencing a very abnormal number of hard-braking events even though you can ascribe every one of them to something outside of your control. Because the implication is that something about your driving habit is increased risk.

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