
Time lost by driving fast - shawndumas
http://www.ncbi.nlm.nih.gov/pubmed/20190187
======
eggoa
I like the assumption implicit in this study: time spent driving is equivalent
to the time spent dead.

~~~
lukifer
Not necessarily; I often listen to audiobooks and the like while driving, or
sometimes I value it as time to think. I've even consumed several dozen
college lectures via MIT and UC Berkeley podcasts.

~~~
gregwebs
I find when an audio-book is truly engaging that I don't realize I just drove
20 miles which probably means I wasn't paying as much attention to the road as
I should have.

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danparsonson
Ah, one of my favourite correlation/causation mix-ups. Proving that increased
speed is associated with an increased accident rate is not the same as proving
that accidents are caused by speeding (and therefore 'accident rate could be
reduced by slowing down').

Personally, I'm more inclined to think that dangerous drivers tend to speed
more than safe drivers, hence the correlation, but in any case I'd love to see
some evidence either way.

~~~
brc
It's not clear whether this applies to urban speeding or highway speeding.

Urban speeding does increase accidents because of the large number of
unexpected events in an urban setting (pedestrians, cars driving into
intersections, etc).

But the main issue I have with speed limit studies is that seem to make this
underlying assumption that everyone follows them. If the core group of
accident-causing people drive fast/drunk/etc regardless of the rules, then
lowering limits/changing rules must have limited effect.

Underlying all this is the government love of speeding taxes. The only problem
is, the marginal return on speeding tax decreases as the tax take goes up.
Because people decide to obey the limit, the tax take starts to go down. Thus
the conundrum for governments - do they set the fines at a level where people
are annoyed but don't mind, or do they increase the fines to the point where
revenue steeply drops.

~~~
cullenking
Two very good points. I speed like crazy on an open highway when on my
motorcycle, but I accelerate very slow and stick to the speed limit when in
the city. Too many bicyclists and pedestrians, not to mention intersections.
Speeding on an empty and straight freeway has considerably less consequence.

I definitely agree that the worst 20% of drivers create 80% of accidents (made
up numbers), which makes most any speed limit conversation null and void.

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jerf
I pretty much stopped caring after "computer model". I find it _very_ hard to
believe the putative results are above the noise threshold of errors in the
model. In fact the cynic in me finds itself a little surprised that that's the
best result they managed to gussy up after fiddling with their model's
parameters. I also can't help but think that they could kiss further funding
goodbye if they reported that driving faster is better.

~~~
nlavezzo
>>I also can't help but think that they could kiss further funding goodbye if
they reported that driving faster is better.

So true...

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Sukotto
This seems akin to economists claiming that a 10% chance at $10,000,000 is
just as good as a guaranteed $1,000,000 because on average you end up with the
same amount of money.

Although it's technically true, any given person is better off choosing the
more certain result.

that's my initial gut reaction. Though I should add that my gut reaction has a
fairly low success ratio when it comes to statistics.

------
chasingsparks
My problem was the conclusion: "As a nation, drivers in the United States
travel slightly too fast and could improve overall life expectancy by
decreasing their average speed slightly."

As a nation, drivers in the United States travel at pretty much the average
speed. (See: <http://en.wikipedia.org/wiki/Speed_limits_by_country>) The
national comparison seems like a rhetorical device, suggesting American's do
something inferior to other countries, therefore we should change to keep up.
Instead, you should only conclude that a decrease in speed could increase life
expectancy.

~~~
houseabsolute
> suggesting American's do something inferior to other countries

No, it very clearly is only suggesting that Americans are doing something
inferior compared to the ideal.

~~~
chasingsparks
Perhaps you're right regarding what the comparison is inviting. It might not
be suggesting cross-country comparisons, but it's still making a normative
statement concerning the ideal. My contention is that it should not do that;
it should only focus on the decreased probability of death by reducing speed.
Weighting the trade-offs is too objective.

(Edit: Also, it's a Canadian paper.)

~~~
fleitz
A Canadian paper on US data, not enough people actually live in Canada for
cars to approach each other on average. (I'm Canadian, but also making fun of
the abuse of averages to describe this data).

------
fleitz
Interestingly, most accidents occur below the speed limit and increasing speed
limits decrease accidents, because limits are artificially low and thus almost
no one heeds them, except for a few people who do who cause accidents because
accidents happen when the variability of speed is greatest.

<http://sense.bc.ca/disc/disc-09.htm>

What speeding does generally is increase the severity of accidents and
alarmingly fast (Thanks, Newton!).

Energy levels follow square law and the human body has a rather low ceiling
for the amount of energy it can absorb. It makes perfect sense that you're
going to see large "averages" especially when the people going most
excessively over the limit are the youngest and most inexperienced.

Now consider that young people also want to live in dense urban environments
where there are a lot of other cars travelling at variable speeds, what you
have is a recipe for high statistical impact accidents with energy levels
following a square law with a low ceiling for death.

Lets look at a rather typical case: Young family, two kids, ages (28,28,2,3)
they are travelling 10 over rushing to daycare and jobs, they run into an 85
year old grandpa driving 20 under. Everyone dies, so you have 10 over
associated with (75-28+75-28+75-2+75-2) or 240 years of life expectancy, now
on the other hand you have 20 under associated with -10 years of life
expectancy. Lets not even get into who caused the accident according to anyone
but a prosecutor.

Do this study on people over 75 and you'll find that old people should
drastically increase the speed of their driving. Do this study on 0-10 year
olds and you'll find that we shouldn't even be driving at all. The only thing
this study says is that young people speed and when they die they have a
disproportionate affect on average life span. The rest of it is just asinine
statistical interpretations on data that have nothing to with speeding, and
everything to do with the fact that the faster you are travelling the more
likely you are to die when you crash. If they wanted to make this
scientifically valid they should publish a chart showing at what age you
should be speeding by how much, because once you're past 2/3rd life expectancy
it's advantageous to speed according to this study, but this isn't about
science, it's about speed = bad, so they can tax (err.. fine) you for doing
it.

It's absolutely idiotic to add those numbers given the age and driving
preferences and think that speeding is counter productive. This study is as
stupid as a study that says that if Bill Gates moves onto your block that
everyone on your block becomes a billionaire. Yes, it works on "average" but
everyone knows that you still have to go to work (you may even have to speed
to get there on time) in the morning if bill gates moves to your block.

I'd much rather get in an accident going 10 over a 50 zone than 5 under in a
100 zone (especially if it's on coming traffic).

Also, in Montana after a Judge invalidated their speeding laws as
unconstitutional the number of accidents dropped.

<http://www.hwysafety.com/hwy_montana.htm>

I'll take real world data over a computer model any day of the week.

~~~
baddox
The pro-speed limit argument falls apart as soon as someone says "but
accidents are more deadly at 90mph" or "your reaction time is less adequate at
90mph." The problem is that while the statement is true, it's also true _any_
lower limit, anything >0.

~~~
alphaoverlord
> The pro-speed limit argument falls apart as soon as someone says "but
> accidents are more deadly at 90mph" or "your reaction time is less adequate
> at 90mph." The problem is that while the statement is true, it's also true
> any lower limit, anything >0.

1\. There is more than one argument for speed limits.

2\. Just because it is true at any lower limit does not invalidate the
statement. This just means that there needs be a balance between efficiency
(higher speeds) and risk of collision (lower speeds). This is regulated, abet
subjectively, through speed limits.

3\. I doubt that it is true at 'any' lower limit. My guess would be that it is
bounded. An accident when you are driving at 5mph is not much less deadly than
an accident at 10mph. The chances that you are not the cause of the accident
is much higher at lower limits.

------
omarqureshi
I'm sure simple things like not looking in mirrors to just being completely
stupid and pulling asshat manoeuvres cause more accidents than speeding

In my time driving, I have never seen accidents caused by excessive speed but
all the time by silliness which would have still resulted in an accident if
people drove slower.

Methods of speed prevention such as cameras probably cause even more accidents
due to last second braking.

What is needed is more education in safety on the road and how to control a
vehicle or even in multi-tasking such as being told to navigate by yourself to
a destination without being told where it as whilst the driver is still a
learner.

------
protomyth
When the speed limit was 55 and you happened to be driving in a rural state
(ND perhaps), fatigue was a greater danger than anything else. The roads are
long and straight and you don't have a huge traffic load. If you covered the
driver's speedometer, the driver would naturally be going 75 - 85 on these
roads (had several incidents with a couple of friends that demonstrated this).
That extra 20 - 30 mph does save quite a lot of time.

I do wonder if the results and conclusions of this study are broken out by
rural / urban roads. Or, like many studies I see, do they lump everything
together or just not study rural areas.

------
tmsh
I've actually been thinking about this a lot (recently started commuting from
the East Bay to San Mateo). So it's awesome that others are too. Personally, I
did a back of the envelope calculation for speeds. Was trying to estimate the
time improvements of 65mph over 55mph v. the likelihood of accident. Suffice
it to say, you all can do the math.

But that's not why I comment. I was actually thinking of a startup idea re:
driving and accidents. Specifically, a site attached to Google Maps, etc.,
where people can register comments about where and how they got involved in an
accident. If there were a way to feed in police report data, that would be
awesome too.

But like the San Mateo bridge. I can see it from my desk. And I can see when
it gets slow, and sometimes I'll check sigalert and note that there's been an
accident (it seems to me usually at the top of the bridge where it's kind of
windy and the furthest left lane has like no shoulder). Or otherwise I've
gotten to know where accidents occur on my commute.

So my point is that all the information should be readily available so that
people can figure out what are the high risk locations of their commute or
trip. I think if you had a simple enough interface that integrated with Google
Maps, people would voluntarily start using it. To my knowledge, there doesn't
exist such a service. Perhaps I'm overly cautious, but I'd use it.

~~~
JeffL
Would also be useful for people to register where they get their speeding and
traffic tickets. As a long time Bay Area resident, I know what stretch of 280
the smokies like to hang out at a lot, and I bet that could be useful
information to others, or even others with a satellite navigation program.
Would be awesome if your GPS always had a threat level indicator based on
accident and ticket likelihoods.

~~~
tmsh
That would be awesome. You could even go the next step and include a HUD
projected on a portion of your windshield...

~~~
firebones
Integrate it with your speedometer, look ahead on your GPS route, factor in
time of day vs. likelihood of presence of law enforcement, take into account
accident data and risk based on location and time of day, and rather than a
HUD, simply have an ambient dash light that boils it all down and glows
related to your risk. Integrate GPS+radar detector+Whispernet (real-time
wardriving for speed traps).

I'm sure with the radar detector this would already break laws in about 30
states, but the core idea still would be viable if all you did was integrate
crash data to alert people to risks in areas where their perception of risk
was off.

If they remake the movie "The Gumball Rally" again in a few years, I'd expect
to see this device featured by one of the teams.

------
mildweed
And here I was worried that due to special relativity's time dilation, I was
blurring by important moments outside my car. Thank goodness they were only
talking about getting into crashes.

~~~
cheald
That was my first thought, too. I was hoping for a mathematical analysis in
the difference in speed of aging between fast and slow drivers. The real paper
was far more useful and mundane.

------
alphaoverlord
Med Decis Making has a Impact Factor of 2.597 while, top journals have Impact
Factors >30

Although it is hard to compare impact values across disciplines, I would
venture to guess this is not the best journal in the world.

[http://www.sagepub.com/journalsProdDesc.nav?prodId=Journal20...](http://www.sagepub.com/journalsProdDesc.nav?prodId=Journal201430)

<http://en.wikipedia.org/wiki/Impact_factor>

------
sdh
I have a crazy idea ...

I'd like to see all drivers tested and graded for driving competency. Just
because you can purchase a car and turn a key doesn't mean you aren't a
vehicular homicide waiting to happen. Next, require all drivers to display
their current driver "grade" on their car like a license plate.

Depending on your driver grade you are allowed to do different things in a
vehicle:

Lowest Grade \- can't drive on the highway (probably eliminating most fatal
highway accidents) \- can't drive vehicles over a certain weight (hopefully
ruling out most minivans and SUVs) \- can't drive high-performance vehicles
(hopefully eliminating a lot of machismo stupidity) \- can't drive above 65
mph \- can't ride motorcycles on public roads (reducing harley and sportbike
sales by about a million percent)

Middle Grade \- can't enter the fast lane of a highway \- can't drive above 75
mph

Highest Grade \- can do pretty much whatever the fuck they want

etc

~~~
toolate
And of course everyone agreeing with you would be in the highest grade.

------
CountHackulus
It seems that the authors of the paper are implicitly suggesting that speed
limit should be lowered across the board.

How about we use that time and money and use it towards better driver
education. Something more than a 20 questions test and 10 minutes in the car
with a tester would be a good start. Maybe some sort of forced driving school?

Then, when everyone's better educated, we can raise the speed limits to
reasonable levels and still have less accidents.

------
gregable
Many (hard to say how many) drivers will drive too fast because they are late
for something. If you assume that their only goal is to either be on time, not
be less late, then speeding makes sense, even in a simulation. Said driver has
nothing to lose - they would be late if they didn't speed, crashes also make
them late, but at least sometimes they won't crash and will indeed arrive on
time.

------
code_duck
This doesn't include the time you can lose by being pulled over and sitting
around for at least 20 minutes? You could especially lose a lot of time
eventually if you have to go to traffic court, or are arrested on an unrelated
charge (i.e. drugs, half the reason police actually are interested in stopping
people for speeding).

~~~
nitrogen
I wonder if drug users compose a higher proportion of speeders than general
members of the population. It seems that random stops should be just as
successful at finding illicit substances.

~~~
code_duck
I've heard police say that they're suspicious of people driving exactly the
speed limit, since it appears they may be trying to be extra careful about
getting pulled over.

------
loewenskind
Just invest more in cars that drive themselves and we can forget all of this
stuff. Our grandchildren (hopefully) are going to think we must have been
terrified driving around in these big metal beasts surrounded by others doing
the same.

------
xenonite
Oh yes, by reducing speed, we could maybe reduce the number of accidents and
thus reduce the travel time.

BUT - after few years, the drivers will adjust! they will still drive slower,
but a little more risky. All the savings will vanish.

------
timmaah
What about the extra time I get to live because I got to my destination
faster? All evens out in the end, right?

~~~
kscaldef
Uh, no, the article is saying precisely that it doesn't all even out in the
end: "A approximately 1-km/h (0.6-mph) increase in speed for the average
driver yielded a approximately 26-second approximate increase (not decrease)
in total expected lost time because the savings from reduced travel time were
more than offset by the increased prospect of a crash."

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jdavid
arguments like this are put together for political reasons. someone is looking
for more revenue.

------
countersignaler
ummm, you can't use observational data to draw conclusions like these. period.
you can use them to hint at causations and effects of changes, but you
absolutely cannot make conclusive statements like those made in this paper.
REALLY bad science.

------
karlzt
off topic: how this submission got into the 100 points feed?

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mthreat
Their conclusion seems incomplete, or maybe they came up with the conclusion
before the study.

Other possible solutions include: increasing driving skill, paying more
attention while driving (no sending text messages), etc

------
lhnn
If -I- didn't crash, I lost no time. Someone else getting in a crash doesn't
increase my travelling average.

~~~
deadmansshoes
It does if you are stuck in traffic waiting for the accident to be cleared.

