
Measuring how deadly our daily activities are - blegh
https://theconversation.com/whats-most-likely-to-kill-you-measuring-how-deadly-our-daily-activities-are-72505
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npstr
What if Shark attacks are so low, because people pay attention to the risk?
Just like airplane travel is safe because of all the regulations, not just out
of itself?

And I dislike measuring the micromorts per population, it should be divided by
those people actually going swimming/surfing, just like riding x miles with a
motorcycle increases your risk of dying by y micromorts, going swimming for a
hours should be increasing your mms by b.

~~~
2muchcoffeeman
Can any statisticians comment why total population is taken into account when
only a portion actually participates in said activities?

~~~
ch4s3
I think it's so that you can more easily compare things apples to apples.

~~~
gwern
I think it's just hard to estimate. How many visits-to-the-beach go into that
shark attack number? It'd be useful to know the per-visit risk for the same
reason it'd be useful to know the per-mile risk for driving, but is harder to
estimate:

"It’s important to be aware, however, that being based on population-level
data, the micromort is not a measure of your personal risk. For example, the
risk calculation for fatal shark attacks is based on the average risk across
the whole population.

So it effectively estimates a risk based on the assumption that all
Australians swim in the deep ocean a similar number of times per year. But if
you live in Alice Springs, you would not expect your risk of being killed by a
shark to be the same as for a surfer who lives on the coast. Similarly, if you
only wade in water up to your knees and don’t swim in deep water, your
personal risks would be different."

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kbutler
> you would divide the number of people who have died due to a shark attack
> each year (on average three to four each year based on recent data) by the
> population of Australia

This method is meaningless, as it assumes the risk of dying by shark attack is
constant regardless of your behavior (e.g., daily swim in chummed waters vs
never entering the water).

The wikipedia article does a better job of micromort-per-unit-of-exposure.

[https://en.wikipedia.org/wiki/Micromort](https://en.wikipedia.org/wiki/Micromort)

e.g., Travelling 17 miles (27 km) by walking (accident) = 1 micromort

But it still doesn't account for differing risk levels, like walking on an
indoor track vs walking in city traffic.

And it doesn't include shark attacks.

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beloch
Approximately half a million people died of malaria in 2015, and that was
after a long trend of decreasing deaths (it used to be much worse)[1]. That's
_deaths_ from malaria, not cases of malaria. If we naively assume everyone on
Earth has equal odds of dying from malaria, that means sharing our planet with
mosquitoes carried a risk of 59.2 micromorts for every human on Earth in 2015.
It's probably gone down slightly since then, but it's still a lot worse than
sharks or skydiving.

Obviously, your real risk is lower in most places, but dramatically higher if
you live in sub-Saharan Africa.

[1][http://www.who.int/gho/malaria/epidemic/deaths/en/](http://www.who.int/gho/malaria/epidemic/deaths/en/)

~~~
wapz
That's very high for the overall population, but I'm guessing the actual
number is close to 0 for say Americans who never left the country (we don't
have malaria deaths contracted from inside the states, do we?). If you are
someone that surfs 4-5 times/week during the season, I guarantee the odds of
you dying from a shark are much higher than dying of malaria.

~~~
wffurr
>> Now approximately 1,500 malaria cases and five deaths are reported in the
United States annually, mostly in returned travelers.

[https://www.cdc.gov/malaria/resources/pdf/fsp/cdc_malaria_do...](https://www.cdc.gov/malaria/resources/pdf/fsp/cdc_malaria_domestic_unit.pdf)

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bootload
_" Interestingly, kangaroos (approximately 0.1 micromorts) pose a risk of
death that is similar to that posed by sharks, but our cute national emblem
does not evoke quite the same fear in us."_

The fear of running into Kangaroos is real. Hitting an 80kg buck at 70km/hr
looks like this:

\-
[https://www.flickr.com/photos/bootload/5037959035](https://www.flickr.com/photos/bootload/5037959035)

\-
[https://www.flickr.com/photos/bootload/5037959047](https://www.flickr.com/photos/bootload/5037959047)

\-
[https://www.flickr.com/photos/bootload/5038593608](https://www.flickr.com/photos/bootload/5038593608)

\-
[https://www.flickr.com/photos/bootload/5147428118](https://www.flickr.com/photos/bootload/5147428118)

~~~
rconti
It strikes me as likely that crashing a car into a kangaroo is not considered
a kangaroo-related death.

~~~
bootload
_" crashing a car into a kangaroo is not considered a kangaroo-related death"_

Roo ran into me. Ran up an embankment. I've been in other situations where the
kangaroos (multiple) are window level travelling along roads at speed. Chance
of kangaroo-related death is there.

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swolchok
The problem with a "unit" of risk like this is that probabilities don't simply
sum like this.

Assuming the probability of dying in each activity is independent, planning to
do a 7000-micromort activity A and then (after appropriate recovery time) an
8000-micromort activity B is not an overall activity with 15000 micromorts of
risk. (The math is close enough when talking about single-digit micromorts,
but it doesn't work in general.)

Pr(dying when doing A followed by B) = Pr({doing A and dying} or {doing A and
surviving and then doing B and dying}) = Pr(doing A and dying) + PR(doing A
and surviving and then doing B and dying) = 7000 / 1000000 + (1 - 7000 /
1000000) * 8000 / 1000000 = 14944 / 1000000

The larger the risks or the longer the series of events, the less accurate the
assumption of linearity. This also doesn't take into account the fact that
dying in extreme activities is _not_ independent; by failing to die in A,
you've demonstrated some small amount of survival fitness.

~~~
swolchok
If the micromort was sold as an expected number of deaths, then I wouldn't
have as much of a problem with it. (My major problem is that you can't die
more than once, so probability seems to be more of a concern than expected
number.) The article calls it "a one-in-a-million chance of dying", though.

For example, playing Russian Roulette once is about 166667 micromorts. Playing
it 6 times is 1 mort of risk, but the probability of dying after 6 plays is
not 1. (It's 1 - (5/6) __6, or about 2 /3.)

~~~
AstralStorm
Welcome to the world of bayesian statistics.

Frequentist approach like this micromort unit ignores conditional probability.

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calcsam
Some of these measurements don't make sense because they (a) lack a unit of
time (b) fail to measure alternatives.

> sitting on a chair (due to the likelihood of falling off it) increases your
> risk of death by approximately 1.3 micromorts.

Is this per day? Per hour? Per year? How does this compare to laying down?
Standing up? Walking around?

~~~
betenoire
That part confused me. It is suggesting that flying around the world is safer
than sitting in a chair to watch tv.

1 micromort for 10K km of air travel, and 1.3 micromorts for sitting in a
chair in your own home.

Considering all the standing, sitting, stairs, ramps, overheads, etc. we do
while traveling, this must be referring ONLY the the flying portion of
flying... very misleading.

~~~
jpttsn
The silliness is even clearer in the finale, the part about "every day you get
out of bed...". You're virtually certain to die if you don't get out of bed
for enough days.

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scottshepard
My favorite stat about micromorts is that motorcycle travel and canoe travel
pose the same risk when measured by distance. That is, one mile of
motorcycling has the same risk of death as one mile of canoeing.

~~~
ehnto
I don't remember the exact numbers anymore, but in Australia at least the
statistics suggest that if you: Don't ride under the influence, Don't ride
without a license, Ride with a helment, and Don't ride an unregistered bike,

Then you have decreased your risk by more than 50%. So using the articles
methods, you will be exposed to less than 200 micromorts.

Servicing your motorcyle and having taken a motorcycle saftey course just once
also increases your liklihood of survival.

Another key part of the dangers are where you ride, being more likely to die
in the CBD than anywhere else, and likely related, just under 50% of accidents
are caused by other motorists than the rider. Many riders seem to think it's
skewed much more toward cars being at fault, it's useful to know that's not
the case.

A final tidbit I recall is that the biggest risk group is 40-60 year old,
returning riders. Not younger new riders as you might have expected.

The interesting part of all of that though is knowing such broad stats can not
truly reveal your personal risk factor, and that there is a lot you can do to
help your cause.

~~~
obstinate
There are other factors too. The less powerful your bike, the safer you are.
That one is actually a pretty significant factor.

I was interested in riding a motorcycle once, but I found that even if I
assumed I was at the safest end of the spectrum, my risk was still many times
that of driving. And the comparison is not apt because many of the risk
factors I mitigate on a motorcycle I also mitigate in a car, for e.g., by
being a careful driver, minimizing the amount of driving I do, driving slowly,
and never driving drunk. So it's not like the motorcycle has become safer
relative to the car. It's just that both skew less risky for me.

So I decided I would not do it. Maybe when I'm older and other risk factors
are more pressing.

~~~
wapz
I probably put in about 100k miles on motorcycles over the years and never had
an accident/incident. I do not agree that a less powerful bike makes you safer
(I only rode sports bikes btw). The slower bikes (250cc or so) generally had
much worse brakes and couldn't accelerate if needed. I found 600cc bikes were
the easiest to control and "safest." That of course is only true if you are
going the same speed as the counterpart (which is difficult especially if
you're riding a 1000cc).

~~~
obstinate
> I probably put in about 100k miles on motorcycles over the years and never
> had an accident/incident.

Cool!

> I do not agree that a less powerful bike makes you safer (I only rode sports
> bikes btw).

You don't need to agree. It's a statistical fact that power and danger are
associated. May not be causal. Probably isn't, in fact.

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sien
Dr David Spiegelhalter runs the Winton programme for the public understanding
of risk at Cambridge.

He has some good stuff on this for more everyday activities like drinking
beer, being 5kg overweight for a day and smoking a cigarette and things.

[https://understandinguncertainty.org/microlives](https://understandinguncertainty.org/microlives)

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Namrog84
Their skydiving estimate and comparison shows some faults with this approach.
If 10 people die a year from x. But those 10 people were people pushing the
limits of skydiving by doing something unusual or intentionally chumming
waters to swim with sharks the numbers are really all wrong

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dabadabadoo
Is anyone else really fascinated by how this article exposes how human beings
are simultaneously irrational and yet, also completely rational when it comes
to fear?

Humans as a whole are irrational when it comes to fear because their fear is
almost never proportional to the actual risk. We're afraid of the one-in-a-
million occurrences, but not the one-in-one-hundred. We don't (yet should)
fear the mundane and the superficial. Humans always strive to be rational, so
why are we so irrational when it comes to fear?

And yet, arguably this is also simultaneously a perfectly rational reaction to
fear. Think about it. If humans were hard-wired to be completely rational when
it comes to fear, i.e. our fears are proportional to the risks involved, we
would be unable to function in our daily lives. We'd be paralyzed by fear from
the moment we wake up. We wouldn't drive cars, or step into bathtubs, or eat
fatty hamburgers. The explanation as to why humans are afraid of shark
attacks, but not driving can be as simple as this: it allows us to exist.

~~~
wffurr
>> We wouldn't drive cars, or step into bathtubs, or eat fatty hamburgers.

Is it really rational to do those things? I put a non-slip mat in my tub, eat
less meat, and generally avoid driving if at all possible. I'm certainly not
unable to function nor continually paralyzed with fear, but my risks of death
from some very common causes are greatly reduced.

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amelius
It would have been interesting if they had compared the risk of all these
activities to the risk of a fatality by an act of terrorism.

~~~
joe_the_user
They could make units of "kilo-terrors" and "mega-terrors", units of a
thousand times the risk of dying in a terror attack and a million times the
risk respectively.

~~~
AstralStorm
I suspect maybe 0.1 micromort of you live in the US, less in France and
Germany, negligible elsewhere.

Higher in Middle East, but I lack precise enough death data for those
countries.

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failrate
The risk of skydiving into a shark's mouth are extremely low. Ironically, if
you were assaulted by a skydiving shark, you would probably die of a heart
attack.

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AstralStorm
The most fun thing is that such risks are generally additive. Not being tied
to number of participating in a given activity makes it a bit better for this
purpose.

That said, instead of frequentist approach a bayesian one would be more
relevant. This would allow including fuzzy participation data like never, once
per year, once per week, daily etc.

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w8rbt
Really, anytime we move faster than we can walk and are on the ground (car,
bus, bike, etc.) we're likely to be involved in an accident that may kill us.

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Havoc
In the end they all die from obesity and booze anyway. Modern life is all
about self-inflicted harm.

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bluebeard
I wonder if Morty from Rick and Morty got his name from micromorts.

