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"Cautious driver" is not a real category. It's not something my crash database can filter on.

Yes, obviously it is not a well-defined category, I mostly hoped that you could filter for taxi or similar.

Anyway, I am not claiming to be the best driver in the world (although I'm 100% safe at least w.r.t. drinking since I don't drink at all), I'm just claiming to be at least as good as a taxi driver, and I would be really really surprised if it turned out that taxi drivers crash their vehicles with the same frequency as the general population.

See in context

36 Deeply Cover Car Crashes?

by jefftk

10th Dec 2023

jefftk

1 min read

36

When there is a train, plane, or bus crash, it's newsworthy: it doesn't happen very often, lots of lives at stake, lots of people are interested in it. Multiple news outlets will send out reporters, and we will hear a lot of details. On the other hand, a car crash does not get this treatment unless there is something unusual about it like a driverless car or an already newsworthy person involved.

The effects are not great: while driving is relatively dangerous, both to the occupants and people outside, our sense of danger and impact is poorly calibrated by the news we read. My guess is that most people's intuitive sense of the danger of cars versus trains, planes, and buses has been distorted by this coverage, where most people, say, do not expect buses to be >16x safer than cars. This also affects our regulatory system, where we push to make high-capacity transportation modes safer (usually) even when this makes them less competitive with cars, shifting more people to driving, and increasing risk overall.

News outlets deciding that car crashes are sufficiently routine that most are not worth deep coverage is probably a commercially reasonable decision, where they expect stories that wouldn't get enough readers or viewers to justify the time investment. But I wonder whether groups trying to shift people away from cars could make up the difference. They could fund a newspaper to deeply investigate crashes, looking into the circumstances that led to the incident and illustrating the human impact of the tragedy. Just because something happens often doesn't mean each time matters less.

(I'm somewhat nervous about "pay for more coverage of events that point in the direction you advocate". I don't know how much this is currently accepted, or what approaches news outlets have in place to keep this kind of arrangementf from producing distorted coverage?)

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[-]Bezzi1y143

My guess is that most people's intuitive sense of the danger of cars versus trains, planes, and buses has been distorted by this coverage, where most people, say, do not expect buses to be >16x safer than cars.

Well, even after eyeballing this graph, I still don't expect to be 16x safer on a bus than while driving my car.

My experience is that car crashes are covered at least by local news, and the overwhelming majority of car crashes I've heard of involved drunk drivers, ludicrous speed, or idiots looking at their smartphones instead of the road. A bus is safer than a car mainly because the average bus driver is more scrupulous than the average car driver.

Do we have data on car crash fatalities limited to public services like taxi? My best guess is that fatalities would decrease by an order of magnitude when you restrict to rule-abiding drivers.

[-]mad1y402

Hi! This is my area of expertise - I work in the road safety field and spent 9 months investigating fatal car crashes. You are right that there are definite "Darwin Award" candidates but there are also deeply relateable ones that could happen to anyone.

Some anecdotes off the top of my head:

A person accidentally had their car in reverse instead of forward when manouvering after leaving a parking spot. This resulted in their car falling into the ocean and the passenger dying.
A very common crash type that usually results in very little damage: two vehicles on a back street colliding. At this particular crash, one of the passengers died.
An ambulence transporting a passenger (so no sirens) was hit by a vehicle driving in the wrong direction. The ambulence passenger died. (i.e. it is not always the driver at fault who dies)
A parent was driving their child home from school, so no doubt took this route every day and was presumably not drunk/high. On this day, they ended up hitting a tree when they were going around a corner (cause: speed? wet? tyres had gone bald? loose sand on the road? the curve was too tight for the speed limit of the road? kid said/did something distracting? who knows! probably a combo!)

Data shows that changing the law on what is permitted (speeds, BAC, seat belts, etc) results in corresponding reductions in fatal crashes. Fatal crashes have halved in Australia (my jurisdiction) since around 1980, despite the population rising.

Here's a good infographic from the WHO showing each country's level of regulation around driving and related activities: https://extranet.who.int/roadsafety/death-on-the-roads/#ticker

The thing about human error is that you make errors ALL THE TIME. You, or other road users, should not die because of your errors. And the errors that tend to result in fatal crashes are not "I was drunk and on meth and speeding" (though those obviously do), the ones that more commonly result in fatal crashes are "I looked away from the road for a second to adjust my GPS and hit a pedestrian".

You'll see statistics quoted around the place about human error is involved in 94% of crashes. That is highly misleading. That doesn't mean 94% of fatal crashes involved a sleepy drunk person at the wheel, "human error" includes stuff like misjudging the gap in traffic, not reading a sign correctly, etc. The sorts of mistakes we all make on the road all the time.

As a road safety professional, it's my role to make sure the road is as easy to perceive as possible (e.g. ensuring adequate sight distances, signs that can be noticed and interpreted at appropriate places, sensible line markings, etc), but also to make the roads forgiving of errors when they do happen.

I think this has ended up being a kind of a rant and I apologise for that but this is a very common misconception and is very damaging to efforts to advance road safety.

[-]Bezzi1y108

The thing about human error is that you make errors ALL THE TIME. You, or other road users, should not die because of your errors. And the errors that tend to result in fatal crashes are not "I was drunk and on meth and speeding" (though those obviously do), the ones that more commonly result in fatal crashes are "I looked away from the road for a second to adjust my GPS and hit a pedestrian".

Well, averting your eyes from the road and your hands from the wheel at the same time in order to touch the screen (rather than reaching a calm spot and stop the car first) is so obviously risky that I was lumping it into "idiots looking at their smartphones".

Yes, I do know that even a minor distraction could be enough to crash your car. My point was that also bus drivers are humans and make errors all the time. I generally drive alone, in silence and with the phone turned off, in order to maximize my attention, and it doesn't seem obvious that a random bus driver should have a lower probability to crash their vehicle than me (given that the average bus driver is also older than me and drives a huge vehicle which is surely more difficult to handle than my small car).

Do you have actual numbers on fatalities caused by cautious drivers?

[-]mad1y81

"Cautious driver" is not a real category. It's not something my crash database can filter on.

You make mistakes when you drive. We all do. It is human nature, and driving is a complex chain of tasks.

If you never speed, never drive after even one drink, never break a single road rule, know every single road rule (in my jurisdiction the road traffic code is some 400 pages long!), never take gaps in traffic that are too close, never go through an orange light too late, never jaywalk, always ensure your car is mechanically up to date, etc etc etc, then you are either pathological about your rule following or a liar.

I do crash analysis as part of my job, almost every day. I can tell you there are PLENTY of bus crashes - buses going before the passengers were sat down resulting in minor injuries, buses hitting pedestrians resulting in hospitalisation, heck I was in a bus about a year ago that rear-ended a car in front of it. I only have access to data in one jurisdiction and I don't believe that data includes taxis, uber drivers, etc. Anecdotally my uber drivers often adjust the GPS when they're driving and tend to speed so I wouldn't call them particularly cautious.

For the record, as far as I know I don't have the right to pull out my jurisdiction's crash data so I won't be able to respond to specific requests. I do know that "bus" is a category of vehicle we have. I don't know whether taxi is.

EDIT:
https://www.9news.com.au/national/liverpool-crash-pedestrian-dies-hit-by-bus-sydney-south-west/6eba1c4a-0825-4828-87c1-b530e5e4e2b5 - a man in Sydney died after being hit by a bus a month ago

https://thewest.com.au/news/traffic/perth-crash-man-hit-by-bus-on-wellington-street-as-police-close-road-c-12809596 (paywall i can't bypass) - a man in Perth was hit by a bus last week

seriously I just searched for "pedestrian hit by a bus" and there are SO MANY in Australia. With a cursory search I see three in Perth (2 million in the greater metro area) in the last six months.

[-]Bezzi1y10

"Cautious driver" is not a real category. It's not something my crash database can filter on.

Yes, obviously it is not a well-defined category, I mostly hoped that you could filter for taxi or similar.

[-]mad1y70

https://acrs.org.au/files/arsrpe/RS050099.pdf <- there's a paper that covers your exact question (comparing crashes in taxis and passenger cars. in case you don't know the terminology, "fleet vehicle" refers to cars that are registered as work cars for an organisation, so more likely to be people on their "best behaviour" as far as drinking/speeding/etc)

Table 5 in particular, per 100 million vehicle kms travelled you have taxis having about half as many fatal crashes as cars but about 50% more injury crashes and maybe 10% more towaway crashes (eyeballing it)

Table 10 also shows that some 30% of taxi drivers involved in crashes weren't wearing seat belts (they're apparently not legally required to in NSW! news to me), which is a pretty big clue that taxi drivers aren't the paragon of careful driving one might assume.

[-]Bezzi1y50

Table 10 also shows that some 30% of taxi drivers involved in crashes weren't wearing seat belts (they're apparently not legally required to in NSW! news to me), which is a pretty big clue that taxi drivers aren't the paragon of careful driving one might assume.

WTF!?

Ok, I suppose I have to update my priors on taxi drivers (man, they even write "There is considerable anecdotal evidence that taxi drivers around the world drive in a manner the rest of the public considers to be unsafe").

Do you have suggestions about other proxies for careful driving?

[-]Ben4mo40

I suspect there is a large variation between countries in how safely taxi drivers drive relative to others.

In London my impression is that the taxis are driven more safely than non-taxis. In Singapore it appears obvious to casual observation that taxis are much less safely driven than most of the cars.

[-]mad1y30

I can't believe you've never heard the stereotype that taxi drivers aren't safe drivers.

I don't know about proxies for "careful driving". That is not my area of expertise.

That said, it's well-known that professional race car drivers die in car crashes at higher rates during their general driving (I don't fancy digging up a citation; you can google it yourself).

I always think of the old chestnut that something like eighty percent of people think they're above average at driving.

I attended a training course recently that stated that educating drivers about the dangers of texting while driving is not very useful, as everyone thinks that they are careful with how and where they choose to text (e.g. only while stopped), but they agree that other drivers shouldn't. Apparently, they reckon it's most effective to tell people "if you text and drive, your kids will grow up to text and drive too". Psychology, eh?

I think all of those are very illustrative of the biases people have in how perceive their operation of their vehicles.

I am relatively convinced that 95% of crashes involve a variety of factors contributing (swiss cheese model). There is rarely, if ever, only one thing that causes a serious crash. As a road safety professional, then, my duty is to make sure that the road forgives any human errors. Safe Systems is the current philosophy in road safety, which states that nobody should be seriously injured or die on the road, even though people do make mistakes. And they do. All the time.

[-]jefftk1y56

I always think of the old chestnut that something like eighty percent of people think they're above average at driving.

This is a silly tangent, but I'm not sure that they're wrong. If I think driving well means getting there as fast as possible and you think it means getting there safely as possible we can each (correctly!) think we're better at driving than the other. So for 80% of drivers to correctly rate themselves above average all we need is 30%+ of drivers to value different behaviors in driving.

[-]faul_sname1y51

Also people may be thinking of "better than average" as " fewer dangerous maneuvers per mile driven than the average across all drivers", for which "I have to take evasive action to avoid a collision with other drivers far more often than they have to do so for me" is a reasonable estimate. And by that standard, if there are a few egregiously bad drivers, that may mean that almost everyone else is above average (not above median, but above average).

[-]avancil1y32

Yes, when it comes to ordinary driving situations, there's only so good you can get, if you can get from A to B without trouble, without annoying and/or scaring your passengers or other people on the road, it's hard to do noticeably better. It's hard to get too much above the median; the 80th percentile driver won't seem that different from the 50th percentile driver. But, you can be really bad and drag the average down. Thus, the average is below the median, ergo most people (most drivers, anyway) are above average drivers. (Even assuming we are using some identical, objective scale, which, as jefftk points out, is not going to be the case.)

[-]Said Achmiz1y-30

“Cautious driver” is not a real category. It’s not something my crash database can filter on.

What makes “cautious driver” “not a real category”? You don’t mean that it’s “not a real category” just because you don’t have data on it in your database… do you?

[-]mad1y43

I mean it doesn't describe something objective/measurable unless you define it explicitly in terms of behaviours. People can do research on e.g. crash rates for drivers who never drink and drive vs frequently drink and drive, people who speed and people who don't, etc.

[-]Said Achmiz1y30

Are you suggesting that there’s no correlation between such behaviors (e.g. between frequency of drinking and driving vs. frequency of texting and driving, or vs. frequency of speeding, or vs. frequency of failing to use turn signals properly, etc.)?

(Because if there are such [positive] correlations, then a “carefulness” factor would emerge, such that we could give the value of the factor for a given driver and it would predict behavioral metrics we hadn’t measured yet. That would be objective and measurable.)

[-]mad1y10

Yeah, okay.

Look at me thinking like an engineer - "but it's not useful from a practical point of view because we don't have access to that data".

[-]Said Achmiz1y30

Sure, that’s a reasonable view.

Of course, the flip side of acknowledging that nonetheless there is such a thing as a “cautious driver” (and even aside from the logic described in the grandparent, it’s clearly much too intuitive a concept to give up—witness the fact that you use it yourself!) is realizing that although we might not have access to that data now, there is no principled reason why we couldn’t have such data…

[-]mad1y30

I think I'm making a distinction between using it colloquially (i.e. I can say that my uncle is tall, which can be true, but it doesn't tell you much about my uncle's actual height) and using it with the rigor that Bezzi implied (i.e. "has someone studied this clear category of cautious drivers"?)

Then again, my example here seems to have failed because people do study tallness: https://www.sciencedirect.com/science/article/abs/pii/000291499390523F , but they crucially define tallness as above the 95th percentile. Other studies I'm glanced at use height as a continuous variable, so who the heck knows.

[-]Joachim Bartosik1y40

First result (I have no idea how good those numbers are, I don't have time to check) when I searched for "fatalities per passenger mile cars" has data for 2007 - 2021. 2008 looks like the year where cars look comparatively least bad it says (deaths per 100,000,000 passenger miles):

0.59 for "Passenger vehicles", where "Passenger vehicles include passenger cars, light trucks, vans, and SUVs, regardless of wheelbase. Includes taxi passengers. Drivers of light-duty vehicles are considered passengers."
0.08 for busses,
0.12 for railroad passenger trains,
0 for scheduled airlines.

So even in the best-comparatively looking year there are >7x more deaths per passenger mile for ~cars than for busses.

[-]Bezzi1y50

This is the same chart linked in the main post.

Again, I am not here to dispute that car-related deaths are an order of magnitude more frequent than bus-related deaths. But the aggregated data includes every sort of dumb drivers doing very risky things (like those taxi drivers not even wearing a seat belt).

Since I'm quite confident to have a particularly cautious driving style, I am not very interested in the total number of fatal car accidents, because lots of people driving recklessly make it skyrocket (I'm not relying entirely on self-judgement here; anecdotally, at least four times I gave a ride to a friend and they mocked me for my overly cautious driving).

To make a comparison, take this document on cancer incidence (chart on page 2). Lung cancer is the most frequent cancer of them all, so you should be more worried about lung cancer than every other cancer, right? Wrong, unless you smoke, since people who have never smoked only make up 10-20% of all lung cancer cases (it follows that you should be 5x less worried about lung cancer if you aren't a smoker, I presume).

I'm now trying to find data on the number of car fatalities not involving people doing stupid things like texting or speeding. I thought that taxi drivers were a good proxy for cautious drivers, but I was very wrong and now I don't know what else to use as a proxy.

[-]mad1y40

I think the thing you're missing is you're still exposed to crashes because of some maniac doing something extremely risky and hitting you.

I'm also a very cautious driver (as you can imagine in my line of work), but I do make mistakes all the time.

This paper seems like it might be interesting for you to read: https://www.pnas.org/doi/epdf/10.1073/pnas.1513271113

I've just had a skim but here's some of my impressions. I might read it in more detail when I get to work today.

It doesn't deal with fatalities (just crashes) but having a quick look at Fig 1, drivers who aren't distracted or impaired are involved in ~28% of crashes. Note that "impairment" also includes things like anger.

Fig 2 is pretty great for you - shows the baseline of each type of impairment, error, distraction and the odds ratio for crashes it's involved in. Not a statistician but I believe that means you're 10 times more likely to get into a crash if you're visibly angry/sad but only 3 times more likely if you're drowsy. Which is very interesting to know.

And that 51% of drivers are observed to be distracted in some way during normal driving condition (which can include "dancing in seat to music" and "interaction with adult passenger".

This paper was just the first result in a scholar search for the term "crash causation factors driver", so this info is relatively easy to find.

[-]Bezzi1y10

I think the thing you're missing is you're still exposed to crashes because of some maniac doing something extremely risky and hitting you.

Yes, but this is true even when I'm not driving. An out-of-control car could crash into me even when I'm walking or sitting inside a bus (and in some cases even when I'm at home).

Anyway, thanks, I'll look into this paper.

[-]Said Achmiz1y20

An out-of-control car could crash into me even when I’m walking or sitting inside a bus.

Indeed this is a perfectly ordinary occurrence. I know at least one person who drives regularly, and has been driving for many years; she’s been involved in exactly one serious car accident, ever—which involved a car hitting her while she was walking.

[-]Joachim Bartosik1y10

Sorry about slow reply, stuff came up.

This is the same chart linked in the main post.

Thanks for pointing that out. I took a brake in the middle of reading the post and didn't realize that.

Again, I am not here to dispute that car-related deaths are an order of magnitude more frequent than bus-related deaths. But the aggregated data includes every sort of dumb drivers doing very risky things (like those taxi drivers not even wearing a seat belt).

Sure. I'm not sure what you wanted to discuss. I guess I didn't make it clear what I want to discuss either.

What you're talking about (estimate of the risk you're causing) sounds like you're interested in how you decide to move around. Which is fine. My intuition was that the (expected) cost of life lost as your personal driving is not significant but after plugging in some numbers I might have been wrong

We're talking 0.59 deaths per 100'000'000 miles.
If we value life at 20'000'000 (I've heard some analyses use 10 M$, if we value QUALY at 100k$ and use 7% discount rate we get some 14.3M$ for infinite life)
So cost of life lost per mile of driving is 2e7 * 0.59 / 1e8 = 0.708 $ / mile

Average US person drives about 12k miles / year (second search result (1st one didn't want to open)), estimated cost of car ownership is 12 k$ / year (link from a Youtube video I remember mentioned this stat) so average cost per mile is ~1$ so 70¢ / mile of seems significant. And it might be relevant if your personal effect here is half or 10% of that.

I on the other hand wanted to point out that it makes sense to arrange stuff in such way that people don't want to drive around too much. (But I didn't make that clear in my previous comment)

[-]jefftk1y21

I took a brake in the middle of reading the post

You choose this post to read and comment on while driving!?

(joking)

[-]mad1y10

"Passenger mile" is not a stat we use in my jurisdiction (we use VKT, vehicle kilometres travelled), but if I'm interpreting it right, then you need to know the average number of passengers to know the number of crashes the driver is involved in. For example, say that each bus has 10 passengers on average, that would put the fatalities per passenger mile at 0.80, which given this is OOM seems pretty similar to cars.

That said, following that to its conclusion you'd end up with trains having some horrendously high rate of crashing, which doesn't pass the sniff test. I think I might be having a failure of logic somewhere here.

[-]Joachim Bartosik1y61

I wanted to say that it makes sense to arrange stuff so that people don't need to drive around too much and can instead use something else to get around (and also maybe they have more stuff close by so that they need to travel less). Because even if bus drivers aren't any better than car drivers using a bus means you have 10x fewer vehicles causing risk for others. And that's better (assuming people have fixed places to go to so they want to travel ~fixed distance).

[-]DanielFilan1y101

In Berkeley there's a sign outside city hall (put up by anti-car activists) listing the number of weeks since someone died of a car collision - perhaps that solution could work here. Altho TBH that sign updated me towards thinking cars are safer than I realized - current count is 59 weeks.

[-]Gunnar_Zarncke1y60

The fatality chart mentioned in the post:

[-]Yair Halberstadt1y52

This is one of the reasons I think people should read a lot more local news. Fatal car crashes are rare enough in an area of 100,000 people that they'll usually be reported. Also positive and more relevant news is much more common - this restaurant just opened, that development just started, local job ads, deep dives into the mayoral candidates, etc. Generally end up better calibrated, less depressed, and more focused on issues that actually effect you.

[-]lsanders1y41

Personally, I’m more familiar with folks creating entirely new nonprofit media outlets to focus on reporting in an area that they believe to deserve better coverage (many of which then seek to partner with traditional publishers on specific projects once they have a demonstrated body of work), rather than directly funding that coverage at an existing paper.

I think Religion News Service is basically an older representative of this approximate model, and topic-focused non-profit journalism organizations like this seem to be popping up more frequently as traditional models of funding journalism come under increasing strain. More current examples that appear to fit this approximate pattern include The Intercept for coverage on surveillance and adjacent issues, The Marshall Project for issues relevant to criminal justice reform, and Anthropocene Magazine for climate change solutions.

[-]Dagon1y20

I'm very skeptical about whether this is achievable. I'd love if "deep" coverage about mundane events were available, especially on dimensions that are usually hidden due to privacy and social norms (age and intoxication levels of drivers, for instance, and type and safety rating of vehicles involved). This would let me update more reasonably for my personal decisions.

I'm even more skeptical that any reporting agency can get the balance right for making "attention given" match "statistical importance". Not only are the incentives wrong (because that's not what readers are willing to read, even if it were free), it would have to err in the other direction to overcome human tendency to overweight outliers and "interesting" events.

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