In article ,
says...

"Stefan" wrote in message
.. .
In article ,
says...

For
instance, mortality rates of bowling are significantly higher than
scuba.

Evidence? I seriously doubt that is actually the case.

The statement also assumes causality. 'Mortality rates OF bowling' is not
the same thing as 'mortality rates WHILST bowling'.


Yes but I doubt the statement is true even regardless of causality.

Some of these nonsense statistics are remarkably persistent. A common
one heard in the climbing community is "There is a 1% chance you will be
killed by climbing in your first year." If you climb, you hear this one
from people all the time. It can be traced to a UK government report
from the 1950s and was clearly wrong even then. Given the way climbing
protection equipment has improved in the meantime, it is wildly
inaccurate today. Nevertheless, people read or hear it, assume it's true
and go on repeating it.

Ian Johnston wrote:

About 3000 people in the UK die in road accidents each year. Assuming
that almost all the population uses roads in some way, that;s 3000 out
of 60 million, which is 1 in 20000.

If the average person lives to the age of 80, it follows that 1 in 80
of the population dies each year anyway (from all causes). Thus you'd
expect 1 in 700000 of the population to die in any hour.

If the average person spends 200 hours a year on the roads, you'd expect
1 in 3500 of the population to die on the roads each year (from all causes).

If in addition 1 in 20000 die from road accidents per year, this suggests
6 in 7 of all road deaths are non-accidental.

Of the 5000 or so glider pilopts
in the UK, about 5 die flying annually which gives a death rate per
annum of 1 in 1000.

You'd still expect 1 in 700k gliders to die each hour simply because they
are part of the general population. And if they spend 20 hours per year
in the air, you'd expect 1 in 35k of gliders to die in the air each year.
If in fact 1 in 1000 die in gliders each year, you'd expect only 1 in 35
air deaths to be non-accidental.

Doesn't that make gliding 30 times as dangerous as being on the road?

In article ,
ldomain says...


Doesn't that make gliding 30 times as dangerous as being on the road?

On an hourly participation basis, that is probably reasonable.

When I used to glide, I once worked out that for an under-40 male, being
a driver roughly doubled your annual mortality risk, and gliding roughly
doubled it again. But on a hourly basis, gliding is certainly more risky
than driving.

On Mon, 17 Apr 2006 11:35:04 UTC, Ronald Raygun
wrote:

: Ian Johnston wrote:
:
: About 3000 people in the UK die in road accidents each year. Assuming
: that almost all the population uses roads in some way, that;s 3000 out
: of 60 million, which is 1 in 20000.
:
: If the average person lives to the age of 80, it follows that 1 in 80
: of the population dies each year anyway (from all causes). Thus you'd
: expect 1 in 700000 of the population to die in any hour.

You'd expect that anyway, from the average lifespan being about
700,000 hours. But maybe that's what you meant?

: If the average person spends 200 hours a year on the roads, you'd expect
: 1 in 3500 of the population to die on the roads each year (from all causes).

You are assuming, though, that "being on the road" and "being likely
to die of natural causes" are independent, which is quite definitely
not the case. In addition, the 3,500 deaths per year does not, as far
as I am aware, count people who have heart attacks on buses and so on
- it's people who dies as a result of road accidents.

: If in addition 1 in 20000 die from road accidents per year, this suggests
: 6 in 7 of all road deaths are non-accidental.

.... and, as per above, not counted in the 3500.

: Of the 5000 or so glider pilopts
: in the UK, about 5 die flying annually which gives a death rate per
: annum of 1 in 1000.
:
: You'd still expect 1 in 700k gliders to die each hour simply because they
: are part of the general population.

Neither "being a glider pilot" nor "dying of natural causes" are
evenly distributed, and they are not independent. Would you expect 1
in 700,000 of both schoolchildren and octogenerians to die every hour?

: Doesn't that make gliding 30 times as dangerous as being on the road?

It's certainly a lot more dangerous, but I don't think your
statistical approach demonstrates how much more dangerous.

Ian

When I used to glide, I once worked out that for an under-40
male, being
a driver roughly doubled your annual mortality risk, and gliding
roughly
doubled it again. But on a hourly basis, gliding is certainly
more risky
than driving.

OK. Did some research from US statistics, causality alone, 2002,
all within 20% (cos I'm a back of an envelope person first time
round):
-------------------------------------

Cars.

38,000 deaths pa, (10 times as many injuries).
15 per 100,000 population (UK, about 7/100,000)
1.5 per 100,000,000 miles
4.5 per 10,000,000 hours

Source: http://www-fars.nhtsa.dot.gov/
--------------------------------------

Boats (12,000,000 - of which sail and Aux sail 40%)

Deaths pa 800 (5 times as many injuries)
0.25 per 100,000 of population
7 per 100,000 boats
2.8 per 10,000,000 hours (heroic assumption; 250hrs per boat pa)
However: sailboats are only 1% of deaths!

Source:
http://www.uscgboating.org/statistic...stics_2002.pdf
---------------------------------------

General Aviation (220,000 aircraft, 30,000,000 hours flown)

Deaths pa 600 (1,800 accidents)
0.7 deaths per 100,000 population
270 deaths per 100,000 aircraft
200 deaths per 10,000,000 flying hours

Source: http://www.ntsb.gov/publictn/2004/ARG0401.pdf
----------------------------------------------

First, don't shout about the detail. I said within 20%. Now, some
points of interest:

1. I'm very surprised that US stats show nearly twice as many
road deaths as UK per whatever. Also the small motor boat death
rates in US are far higher as a proportion than in UK.

2. I'm now quite clear why insurance rates for general aviation
are so high, and why boat insurance is similar to car insurance
rates.

3. I think on a per hour basis, car driving in UK is about quits
with boats, though sailboats may be safer! That would take more
research, and I'm in Easter Holiday trouble already.

4. None of this takes account of person to person skill
variations. Surveys have routinely shown that 80% of car drivers
believe that their skills are above the average, if not
exceptional. Pilots are similar. I've never asked sailors - just
examined them. So I've got a good idea what the average skill
levels of examinee sailors are - and they're the skilled minority.
My view is that the personal skill levels are not relevant to boat
safety - I think 'fear factor' is more important. Avoiding things
you can't do, or being very careful when trying them. Most boat
deaths are due to not wearing buoyancy aids, or being under the
affluence of incohol (see reference).
--
JimB
http://www.jimbaerselman.f2s.com/
Describing some Greek and Spanish cruising areas

On Mon, 17 Apr 2006 08:33:00 UTC, Stefan wrote:

: Not true of Nimbus's sport either (mine also at one time). There are
: glider pilots who have been knocked out of the sky by other aircraft,
: typically other gliders in crowded thermals.

I knew an instructor at Portmoak (Scottish Gliding Union) who looked
up once to see the mainwheel of a slowly overtaking glider less than
two feet above his canopy. Thank goodness he had the presence of mind
not to dive away...

Ian

--

Ric wrote:
The most dangerous part of any "dangerous sport", whether sailing,
scuba-diving, climbing etc, is driving in your car to get there....


A curious statement - it almost seems reasonable. How does it apply
to boating in general?

There are about 180 million cars in the US, and 12 million registered
boats, so the ratio is 15 to one. The number of boating fatalities is
around 700, but this doesn't include drowning while swimming off a
boat which is a substantial factor, so I will exercise some
prerogative and call it an even 1000 deaths. There are 30000 auto
related deaths, so that ratio is 30 to one.

Thus, when counted by registered vehicles, auto fatalities are twice
as frequent. However, the story gets muddied by the fact that human
powered boats (canoes, kayaks, rowboats) are not registered in most
situations, yet are involved in a substantial number of fatalities.
This tends to make boating seem even safer, vehicle by vehicle.

The bottom line is that if you have a car and a boat, you're more
likely to die in the car. However, if you consider that most boaters
only use a small portion of their driving time going to their boat, I
would guess that on a given "boating day" the boating portion is more
dangerous.

There is a whole other side to this, however. Those of us with larger
sailboats know that our boats are far, far safer than the small boats
that seem to cause all the problems. For example, we have stays to
hang onto when we pee overboard! Does this hold up? Auxiliary
sailboats make up about 1.2% of the fleet, but were involved in only
1.2% of the fatalities. Hmmm. OK, well at least larger boats must
safer: 4.6% of the registered fleet is over 26 feet, and 5% of the
fatalities involved boats over 26 feet. Hmmm.

One thing is clear when looking at the statistics: most deaths occur
from "stupid" behavior. "Overall, carelessness/reckless operation,
operator inattention, operator inexperience, and excessive speed are
the leading contributing factors of all reported accidents."

http://www.uscgboating.org/statistic...stics_2004.pdf

In article , says...

There are about 180 million cars in the US, and 12 million registered
boats, so the ratio is 15 to one. The number of boating fatalities is
around 700, but this doesn't include drowning while swimming off a
boat which is a substantial factor, so I will exercise some
prerogative and call it an even 1000 deaths. There are 30000 auto
related deaths, so that ratio is 30 to one.


Both those accident rates are higher than the UK, whose population is
around 25% of the USA. Boating deaths appear vastly higher in the USA. I
wonder why?

UK road deaths around 3200 in 2005 with 30M registered cars.

Boat-related deaths:

http://www.dft.gov.uk/stellent/group.../page/dft_foi_
610522.pdf shows numbers reported to the Marine Accident Investigation
Board. Incidents involving deaths, maybe half a dozen a year.

http://www.rospa.com/waterandleisure...atersafety.htm
lists 22 boating drownings in the UK in 2004.

There is no legal requirement to register small craft in the UK so
nobody knows how many there are. Also certainly several million.

AMPowers wrote:
Gary,

I think an excellent book on this subject is "Deep Survival". It
discusses "who lives, who dies, and why" in regards to "extreme sports.
The arguments made in it are quite interesting and apply to this topic.

It seems that generally what kills people, more often than not, is poor
decision making, inadequate training/skill and improper preparation. All
of those qualities are just as applicable to driving as to sports.

I don't think the argument can be made "objectively" that driving is any
more or less dangerous than anything else unless you are willing to
theorize an individual who's training/skill, preparation and decision
making skills are objectively equal for each endeavor. Then comparing
that individual in each activity would make sense. The problem with
this is that measuring such things is almost always impossible.

Instead, people resort to statistics of entire populations. For
instance, mortality rates of bowling are significantly higher than
scuba. Why? Because more people who bowl are at greater risk of heart
attack and stroke. The sport itself is not really more dangerous, just
the population practicing it.

When one tends to look at the statistical averages, one ignores the
population's (and consequently the individual's) training/skill,
preparation and decision making abilities I think this isn't really a
"fair" comparison, but it does at least give you some relative sense of
the danger in terms of the population, which is what insurance agencies
(the folks who compile this information) really care about.

While I do believe that any activity has some danger (including driving)
I think more often than not the real level can not be truly,
scientifically determined for the individual. So, while boating may be
dangerous, whether it is more so than driving really comes down to who
is doing it at the time.

Robb

Good point, well articulated. I'll look for the book.

Gary

Both those accident rates are higher than the UK, whose
population is
around 25% of the USA. Boating deaths appear vastly higher in
the USA. I
wonder why?

Nice to see a rational approach!

Partly, US has a far more rigorous reporting system. Nearly half
boat deaths occur in small rowboats and motorised fishing boats
pottering around without lifejackets. These don't interest the
MAIB. Additionally, UK appears to have more sail and auxiliary
sail boats active compared to these small vessels. In US the
safety of these sail vessels is *much* higher - so that could be
an equaliser.

Your RoSPA data included only drownings in UK. Dig into their
leisure industry reports (LASS) and you'll find they report
typically 5,000 to 6,000 injuries over about 11 categories of
vessel (which is confusing!). However, the likely ratio of
injury/death will be around 1/5 (the US boating rate) to 1/10 (US
and UK car rate). This implies around 500 to 600 deaths from
boating in UK per year. I know - heroic assumption!

UK road deaths around 3200 in 2005 with 30M registered cars.

Boat-related deaths:

http://www.dft.gov.uk/stellent/group.../page/dft_foi_
610522.pdf shows numbers reported to the Marine Accident
Investigation
Board. Incidents involving deaths, maybe half a dozen a year.

http://www.rospa.com/waterandleisure...atersafety.htm
lists 22 boating drownings in the UK in 2004.

There is no legal requirement to register small craft in the UK
so
nobody knows how many there are. Also certainly several million.

Estimates from consumer market surveys around 1995 put the numbers
of people who regard themselves as participating regularly in
sailing activites around 3,000,000. Not a very useful stat, but
it's the best I've got!

--
JimB
http://www.jimbaerselman.f2s.com/
Describing some Greek and Spanish cruising areas