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HOW DANGEROUS IS CYCLING? DEPENDS ON WHICH NUMBERS YOU EMPHASISE.



 
 
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  #151  
Old May 25th 19, 09:00 PM posted to rec.bicycles.tech
Frank Krygowski[_4_]
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Posts: 10,538
Default HOW DANGEROUS IS CYCLING? DEPENDS ON WHICH NUMBERS YOU EMPHASISE.

On 5/24/2019 12:36 PM, jbeattie wrote:
On Wednesday, May 22, 2019 at 4:43:11 PM UTC-7, Frank Krygowski wrote:
On 5/22/2019 4:49 PM, jbeattie wrote:
On Tuesday, May 21, 2019 at 2:07:39 PM UTC-7, Frank Krygowski wrote:
On 5/21/2019 11:29 AM, jbeattie wrote:
On Monday, May 20, 2019 at 4:10:56 PM UTC-7, Frank Krygowski wrote:
On 5/20/2019 5:07 PM, jbeattie wrote:

Tom, statistically, you did not have any of your head injuries. They were imagined...

IOW: "Math is HARD!!!"


It's not math. It's statistics -- where two plus two may equal four, depending on who you are. Large population studies say little or nothing about the risks encountered by individual cyclists in particular areas or engaging in specific types of cycling. Tom is an example -- as are most of my cohorts. It doesn't take a math genius to recognize that lumping together the accident rates of NYC bike messengers and Sun City retirees is going to create a combined rate that is not accurate for either group.

Jay, that has nothing to do with your quip "Tom, statistically, you did
not have any of your head injuries."

Obviously, that's not what the statistics say. But unfortunately, there
are plenty of people who seriously engage in your logical fallacy. One
way it's been expressed is "Yes, there may be only one bike fatality per
ten million miles ridden. BUT WHAT IF THAT ONE IS _YOU_??"

What logical fallacy?


The same one that leads millions of people to waste billions of dollars
on lottery tickets. "It doesn't matter if the odds are hundreds of
millions to one against me. What if _I_ win?"


Ah, no. The whole point of my post is that unlike a lottery, the odds of wining or losing are different for each cyclist depending on a number of variables. Whether those odds are so high for a particular cyclist to create a psychological or practical barrier to cycling is a whole other matter.


The same one that leads people to shun vaccinations for their kids. "The
scientists have numbers claiming vaccinations don't cause autism, but
what if they're wrong about _MY_ kid?"

It's the belief that every individual is totally unique, and that large
population data can say nothing about any person's chances of any
occurrence.

Who's on the other side of this debate? Medical science, for one - with
large medicine trials that confirm that medicine A is beneficial; and
with other trials that show that medicine B is no better than a placebo.
They do this by testing large numbers of patients; and the assumption is
that the next patient won't be miraculously different. He'll probably
respond about the same way.


Insurance companies are also on the side of statistics. They take in
billions of dollars betting against the idea that everyone is absolutely
unique. They know that there are individual differences; but they bet
heavily on aggregate data. Of course some individuals fall far enough
outside the norm to cost the insurance folks money; but the vast
majority of their customers meet their predictions well enough to ensure
healthy profits.



Both of these examples miss the point -- first, in large scale clinical trials, the cohort is carefully matched resulting in the approval of a drug for a very limited purpose (and a lot of off-label use for others). Health insurers simply eliminate coverage for pre-existing conditions, include annual maximums and re-insure large risks. They can use relatively blunt statistics and control risk in other ways. Accident policies may be denied to hang-glider users



Your statistics are so blunt, its like saying that a man has a one in 1,000 chance of getting ovarian cancer because that is the national statistic.


Of course, you have to choose the applicable data for the proper cohort.
(Although, weirdly enough, we're now in an age where gender is
purportedly a matter of opinion!)


And regarding large population studies: It's true that every large
population has its probability distribution, usually a bell curve. And
there are certainly individuals out on each tail end of each bell curve
- the good end and the bad end.

But that does not mean the studies say "little or nothing" about
individual risks. Unless the individual is riding his bike off the roof
of a skyscraper, his individual values are best thought of as
modifications of the mean value. One individual will very likely be
within two standard deviations of the mean. He's very unlikely to be
more than three standard deviations away from the mean. Or in other
words, almost everybody is almost average.

My lifetime mileage is approaching 300,000 miles which is a multiple of standard deviations above the norm and yet you would put me in the same cohort as the once-a-year beach-bike cruiser at the local resort.


Somewhere upthread, we were talking about your individual crashes or
injuries, which you proclaimed to be many.


It depends what you call "many." Compared to my MTB friends, it is few.


Your lifetime mileage is extremely impressive. It would be interesting
to take your personal injury count, divide by your lifetime mileage, and
see how far you lie outside the available averages - recognizing that
the "average" data is very rough.

Frankly, what I'd expect is that you (and most other super-dedicated
riders) would have much lower per-mile crash rates than average. FWIW,
Forester claimed this in one of his books.


Again, proving my simple point -- individuals have individual risk profiles. Mine is not the same as yours or Danny MacAskill's.


But it depends. Danny MacAskill also has tons of mileage; but I'm sure
he has tons of crashes. (He actually does ride his bike off rooftops.)
And I've known avid riders who gave it up because they had too many
crashes. Extreme risk takers and extremely clumsy people must be a big
part of the "bad" tail of the bell curve.

Above all, if a person chooses situations and behaviors that are well
within his skills and capabilities, he can place himself further on the
"good" side of that bell curve. If he takes excessive risks, he places
himself further toward the "bad" side.

An individual with a large number of crashes almost certainly didn't get
those because statistics failed. It's because one way or other, his
choices were bad.

Thank god you're not a doctor -- you'd ignore family history, work exposure and every other relevant factor in predicting whether a particular patient was at risk for a specific disease.

All the world is not the same, and everyone in the world is not exposed to the same risks. For example, most of the pedestrian deaths in Portland happened on a handful of roads. You are at risk crossing those roads -- more so than crossing any other roads in Portland. You're crazy to ignore the specific circumstances under which others ride, walk, sleep, garden, etc.


I'm not ignoring them. But I'm saying almost everyone is almost average.
That's true within any properly selected cohort.

If someone's experience falls far outside the norm for his cohort, then
something very strange is happening; or perhaps there's been some
mis-measurement.

Here's a specific example: The best data available (from several
sources) estimates that there are about ten million miles ridden in the
U.S. between bike deaths. (Actually more, but that round number will
suffice.) And the best data I could find said about 45% of those were
actually caused by TBI. Some others claim a higher TBI percentage,
although the "75%" claim seems imaginary.

So, again using very round numbers, there are probably at least 15
million miles ridden between bicycling TBI deaths. Yet I've recently
read a claim "My helmets saved my life three times!"


Fundamentally, this is all about helmets. No? And the crushing fear of MHLs. This is unfortunate because it turns the question of personal risk into a political discussion with statistics being used to prove a point.

What's the most rational conclusion? Seems to me one possibility is that
person is an ASTONISHINGLY bad rider, way out beyond the 99.9999th
percentile. Or much more likely, that person is flat out wrong - that
none of the three head impacts would have killed him, despite his
heartfelt belief.

IOW, I don't think the people who make that claim or very similar claims
are really that far outside the norm.

And - "Completely separate issue" warning! - I think it's still true
that in most incidents when a bicyclist falls, he (or she) made a
mistake. They could have avoided it if they had done things differently,
including shunning a risk that was outside their capability at the moment.


Which again proves my point. Risk is different for different riders. If you JRA at 12mph on dry village streets, you are at low risk of injury. If you ride in snow, ice and rain on steep, broken roads, you are at a higher risk of injury. If you do laps in the Arc d'Triumph roundabout or filtering through London traffic, you're in a whole other risk category. And then, each of those categories is modified further by skill and experience.


Now that I have some time, let's back up a bit. Maybe some summary and
clarification is needed.

Here's my position, based on years of reading many reams of studies and
data. (BTW, I'm applying this to on-road riding, not mountain biking,
where tricks and risks are part of the culture for many riders.)

Ordinary cycling is not an unusually dangerous activity. Serious
injuries among bicyclists are pretty rare, in terms of miles per injury.
Fatalities are far more rare, either per mile or, nationally, per year.
Traumatic brain injuries fatalities of cyclists are even more rare. And
the benefits of bicycling have been shown repeatedly to tremendously
outweigh the risks.

Yes, I'm sure the risk of cycling follows a normal distribution, with
dangers being greater for some and less for others. But the data that
confirms my views already includes wrong way riders, drunk ones,
no-lights-at-night ones, red light runners, clumsy people, extreme risk
takers, etc. Competent and reasonably cautious riders certainly have
lower risks than average. For them, cycling is even safer.

Despite all that, study after study has shown that one of the most
important reasons (usually THE most important reason) people don't ride
bikes is because they think it's too dangerous. Those people are wrong.

And most "bike safety" propaganda now says one should not ride without
lots of unusual equipment. That propaganda is wrong.

Finally, I think that if I took (another) on-road ride this evening and
injured myself, I'd probably say it was because of a mistake I made.

Now what are you disagreeing with?

Are you saying that bicycling actually is really dangerous? Even for
competent, lawful cyclists?

Are you saying the overall data should be completely thrown out, not
even considered, because it can't be proven to apply to any one
particular cyclist?

Are you saying that we really, really should not ride without most or
all of the "safety" gimmicks promoted by various hand wringers?

Are you saying that your personal crashes were all not your fault, and
that anyone would have had the same crash in the same circumstances, no
matter how skilled and careful they were?

Are you saying my lack of crashes (just two moving on-road crashes since
beginning adult cycling in 1972) are the result of only riding 12 mph on
quiet village streets?

Or are you just saying nothing is knowable, everything is random, and we
should abandon all scientific inquiry?

--
- Frank Krygowski
Ads
  #152  
Old May 25th 19, 11:07 PM posted to rec.bicycles.tech
jOHN b.
external usenet poster
 
Posts: 2,421
Default HOW DANGEROUS IS CYCLING? DEPENDS ON WHICH NUMBERS YOU EMPHASISE.

On Sat, 25 May 2019 15:12:43 -0400, Frank Krygowski
wrote:

On 5/25/2019 2:41 AM, Sir Ridesalot wrote:
On Saturday, May 25, 2019 at 2:22:22 AM UTC-4, John B. wrote:
Snipped
One might ask the question of whether there is some ulterior reason
for wanting to build bike paths? After all, the advocate has been
posting here for years with no mention of bicycle paths until very
recently. Was he struck by lightening while on the road to Damascus?
Are there other reasons?
--
cheers,

John B.

WAY OFF TOPIC but...

Just wondering why so many Americans/ex Americans use the word "lightening" (to make lighter) rather than the word "lightning" (a bolt/sheet of visible electricity in the sky)? I've seen this in so many places including online literature that it's made me curious.


It's just a common misspelling, and one that software spell checkers
don't flag as wrong because it's still a legitimate word in other contexts.

An even more common one is "loose" instead of "lose." I've known very
highly educated, very intelligent people who repeatedly make that mistake.

I wouldn't loose any sleep over the mispellings.


As Mark Twain wrote, "I don't see any use in having a uniform and
arbitrary way of spelling words. We might as well make all clothes
alike and cook all dishes alike. Sameness is tiresome; variety is
pleasing. "
--
cheers,

John B.

  #153  
Old May 26th 19, 12:14 AM posted to rec.bicycles.tech
JBeattie
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Posts: 5,870
Default HOW DANGEROUS IS CYCLING? DEPENDS ON WHICH NUMBERS YOU EMPHASISE.

On Saturday, May 25, 2019 at 1:00:56 PM UTC-7, Frank Krygowski wrote:
On 5/24/2019 12:36 PM, jbeattie wrote:
On Wednesday, May 22, 2019 at 4:43:11 PM UTC-7, Frank Krygowski wrote:
On 5/22/2019 4:49 PM, jbeattie wrote:
On Tuesday, May 21, 2019 at 2:07:39 PM UTC-7, Frank Krygowski wrote:
On 5/21/2019 11:29 AM, jbeattie wrote:
On Monday, May 20, 2019 at 4:10:56 PM UTC-7, Frank Krygowski wrote:
On 5/20/2019 5:07 PM, jbeattie wrote:

Tom, statistically, you did not have any of your head injuries. They were imagined...

IOW: "Math is HARD!!!"


It's not math. It's statistics -- where two plus two may equal four, depending on who you are. Large population studies say little or nothing about the risks encountered by individual cyclists in particular areas or engaging in specific types of cycling. Tom is an example -- as are most of my cohorts. It doesn't take a math genius to recognize that lumping together the accident rates of NYC bike messengers and Sun City retirees is going to create a combined rate that is not accurate for either group.

Jay, that has nothing to do with your quip "Tom, statistically, you did
not have any of your head injuries."

Obviously, that's not what the statistics say. But unfortunately, there
are plenty of people who seriously engage in your logical fallacy. One
way it's been expressed is "Yes, there may be only one bike fatality per
ten million miles ridden. BUT WHAT IF THAT ONE IS _YOU_??"

What logical fallacy?

The same one that leads millions of people to waste billions of dollars
on lottery tickets. "It doesn't matter if the odds are hundreds of
millions to one against me. What if _I_ win?"


Ah, no. The whole point of my post is that unlike a lottery, the odds of wining or losing are different for each cyclist depending on a number of variables. Whether those odds are so high for a particular cyclist to create a psychological or practical barrier to cycling is a whole other matter.


The same one that leads people to shun vaccinations for their kids. "The
scientists have numbers claiming vaccinations don't cause autism, but
what if they're wrong about _MY_ kid?"

It's the belief that every individual is totally unique, and that large
population data can say nothing about any person's chances of any
occurrence.

Who's on the other side of this debate? Medical science, for one - with
large medicine trials that confirm that medicine A is beneficial; and
with other trials that show that medicine B is no better than a placebo.
They do this by testing large numbers of patients; and the assumption is
that the next patient won't be miraculously different. He'll probably
respond about the same way.


Insurance companies are also on the side of statistics. They take in
billions of dollars betting against the idea that everyone is absolutely
unique. They know that there are individual differences; but they bet
heavily on aggregate data. Of course some individuals fall far enough
outside the norm to cost the insurance folks money; but the vast
majority of their customers meet their predictions well enough to ensure
healthy profits.



Both of these examples miss the point -- first, in large scale clinical trials, the cohort is carefully matched resulting in the approval of a drug for a very limited purpose (and a lot of off-label use for others). Health insurers simply eliminate coverage for pre-existing conditions, include annual maximums and re-insure large risks. They can use relatively blunt statistics and control risk in other ways. Accident policies may be denied to hang-glider users



Your statistics are so blunt, its like saying that a man has a one in 1,000 chance of getting ovarian cancer because that is the national statistic.

Of course, you have to choose the applicable data for the proper cohort.

  #154  
Old May 26th 19, 12:18 AM posted to rec.bicycles.tech
Andre Jute[_2_]
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Posts: 10,422
Default HOW DANGEROUS IS CYCLING? DEPENDS ON WHICH NUMBERS YOU EMPHASISE.

On Saturday, May 25, 2019 at 12:25:58 PM UTC+1, Duane wrote:
Andre Jute wrote:
On Friday, May 24, 2019 at 11:36:33 PM UTC+1, Duane wrote:
Andre Jute wrote:
On Friday, May 24, 2019 at 5:36:16 PM UTC+1, jbeattie wrote to Krygowski:

Risk is different for different riders. If you JRA at 12mph on dry
village streets, you are at low risk of injury. If you ride in snow, ice
and rain on steep, broken roads, you are at a higher risk of injury. If
you do laps in the Arc d'Triumph roundabout or filtering through London
traffic, you're in a whole other risk category. And then, each of those
categories is modified further by skill and experience.

-- Jay Beattie.

I've given up trying to educate that obstinate jerk, Frank Krygowski. But
I must congratulate you on a good job, though your success will, like all
past efforts, be temporary. Bad pennies keep turning up.

You might add that, if you're on a road bike with narrow tyres, your risk
of an incident is higher than if you're on balloons (50mm wide and up)
though only if on downhills you proceed at the same pace as you would on
narrow tyres rather than taking advantage of the greater capability of the balloons.

Andre Jute
2.0 bar


Jay is correct. Risk is different for different riders and even for the
same rider in different circumstances. All cycling is not the same.
Sometime I’m trudging through the traffic alone commuting to work.
Sometimes I’m out in the country in a group pushing it. Both have
different parameters regarding risk etc. Some cyclists do only one or the
other. Some do both. Hard to group them together statistically. And what
would be the point anyway?

--
duane


I understand what you two are getting at, and I agree. But the actuary of
an insurance company would be interested in the average danger in a
representative year to all the cyclists in his demographic universe,
simply as a base number from which to offset the factors we've already
cited, plus no doubt others so that individual quotes can be prepared
that will be different for me, riding in a country area and you, riding
in a great metropolis. We've already had an example of where it has
become difficult to get insurance for a mass ride of very occasional
riders, where the cause might be insufficient data to make a rational
quote, too many payouts for automobile crashes on that particular piece
of road (from an insurance company's viewpoint not irrelevant at all),
prior unprofitable experience insuring such mass bicycle rides, or simply
common sense skepticism.

You have to keep these two ideas, one based on demographics in large
universes, one based on particular risks in particular places, separate,
because the statistical principles applying to them are quite as
different as the underlying assumptions of macro- and
micro-economics.That is what's so tiresome about Krygowski's ignorant
insistence that all you need is a technician's rote-learned math and
Leontiev is your uncle: hey, presto, you understand statistics! This
ignorance and insensitivity to people, coupled to immorality, is what
drives Krygowski's repeated attempts to argue from the particular (that
what he himself does is superior to what anyone else does) to the
general, and then to assume that 200 or 300 unnecessarily dead cyclists
every year don't matter.

Andre Jute
Actuaries rule


Well statistics in the macro sense can serve to direct solutions to macro
problems but don’t serve much use on the micro level. I think I was taught
that in a first year stats course. But I think that’s what you just said.

--
duane


You rock, Duane!

Andre Jute
Don't let the bull****ters baffle you
  #155  
Old May 26th 19, 12:32 AM posted to rec.bicycles.tech
Andre Jute[_2_]
external usenet poster
 
Posts: 10,422
Default HOW DANGEROUS IS CYCLING? DEPENDS ON WHICH NUMBERS YOU EMPHASISE.

On Saturday, May 25, 2019 at 3:18:37 PM UTC+1, sms wrote:
On 5/25/2019 4:25 AM, Duane wrote:

snip

Well statistics in the macro sense can serve to direct solutions to macro
problems but don’t serve much use on the micro level. I think I was taught
that in a first year stats course. But I think that’s what you just said.


Statistics are notoriously bad in protecting you in a head-impact crash.


You got the wrong mindset, Scharfie. Think Nietsche and let the Oberguru Krygowski put you on the path to willpower and taking the lane, and you'll never need a stahlhelm again.

Andre Jute
What cat? -- Erwin Schroedinger
  #156  
Old May 26th 19, 01:35 AM posted to rec.bicycles.tech
Frank Krygowski[_4_]
external usenet poster
 
Posts: 10,538
Default HOW DANGEROUS IS CYCLING? DEPENDS ON WHICH NUMBERS YOU EMPHASISE.

On 5/25/2019 6:07 PM, John B. wrote:
On Sat, 25 May 2019 15:12:43 -0400, Frank Krygowski
wrote:

On 5/25/2019 2:41 AM, Sir Ridesalot wrote:
On Saturday, May 25, 2019 at 2:22:22 AM UTC-4, John B. wrote:
Snipped
One might ask the question of whether there is some ulterior reason
for wanting to build bike paths? After all, the advocate has been
posting here for years with no mention of bicycle paths until very
recently. Was he struck by lightening while on the road to Damascus?
Are there other reasons?
--
cheers,

John B.
WAY OFF TOPIC but...

Just wondering why so many Americans/ex Americans use the word "lightening" (to make lighter) rather than the word "lightning" (a bolt/sheet of visible electricity in the sky)? I've seen this in so many places including online literature that it's made me curious.


It's just a common misspelling, and one that software spell checkers
don't flag as wrong because it's still a legitimate word in other contexts.

An even more common one is "loose" instead of "lose." I've known very
highly educated, very intelligent people who repeatedly make that mistake.

I wouldn't loose any sleep over the mispellings.


As Mark Twain wrote, "I don't see any use in having a uniform and
arbitrary way of spelling words. We might as well make all clothes
alike and cook all dishes alike. Sameness is tiresome; variety is
pleasing. "


I recently read an article about Noah Webster and Benjamin Franklin
trying to reform American spelling by getting rid of double letters,
superfluous letters, silent letters, etc. Using new symbols so each
letter signified just one sound. Their ideal was completely phonetic and
uniform.

Obviously, it failed badly.


--
- Frank Krygowski
  #157  
Old May 26th 19, 03:46 AM posted to rec.bicycles.tech
jOHN b.
external usenet poster
 
Posts: 2,421
Default HOW DANGEROUS IS CYCLING? DEPENDS ON WHICH NUMBERS YOU EMPHASISE.

On Sat, 25 May 2019 20:35:30 -0400, Frank Krygowski
wrote:

On 5/25/2019 6:07 PM, John B. wrote:
On Sat, 25 May 2019 15:12:43 -0400, Frank Krygowski
wrote:

On 5/25/2019 2:41 AM, Sir Ridesalot wrote:
On Saturday, May 25, 2019 at 2:22:22 AM UTC-4, John B. wrote:
Snipped
One might ask the question of whether there is some ulterior reason
for wanting to build bike paths? After all, the advocate has been
posting here for years with no mention of bicycle paths until very
recently. Was he struck by lightening while on the road to Damascus?
Are there other reasons?
--
cheers,

John B.
WAY OFF TOPIC but...

Just wondering why so many Americans/ex Americans use the word "lightening" (to make lighter) rather than the word "lightning" (a bolt/sheet of visible electricity in the sky)? I've seen this in so many places including online literature that it's made me curious.

It's just a common misspelling, and one that software spell checkers
don't flag as wrong because it's still a legitimate word in other contexts.

An even more common one is "loose" instead of "lose." I've known very
highly educated, very intelligent people who repeatedly make that mistake.

I wouldn't loose any sleep over the mispellings.


As Mark Twain wrote, "I don't see any use in having a uniform and
arbitrary way of spelling words. We might as well make all clothes
alike and cook all dishes alike. Sameness is tiresome; variety is
pleasing. "


I recently read an article about Noah Webster and Benjamin Franklin
trying to reform American spelling by getting rid of double letters,
superfluous letters, silent letters, etc. Using new symbols so each
letter signified just one sound. Their ideal was completely phonetic and
uniform.

Obviously, it failed badly.


Mark Twain also wrote a story about streamlining the English
language, the story is too long to post here but the results was:

"Fainali, xen, aafte sam 20 iers ov orxogrefkl riform, wi wud hev a
lojikl, kohirnt speling in ius xrewawt xe Ingliy-spiking werld." :-)

In Several countries where I have lived, Japan for example, they
cannot understand how anyone can misspell a word as their language is
wholly phonetic and if they can pronounce it they can spell it.


--
cheers,

John B.

  #158  
Old May 29th 19, 08:23 PM posted to rec.bicycles.tech
Tom Kunich[_5_]
external usenet poster
 
Posts: 1,231
Default HOW DANGEROUS IS CYCLING? DEPENDS ON WHICH NUMBERS YOU EMPHASISE.

On Tuesday, May 21, 2019 at 2:07:39 PM UTC-7, Frank Krygowski wrote:
On 5/21/2019 11:29 AM, jbeattie wrote:
On Monday, May 20, 2019 at 4:10:56 PM UTC-7, Frank Krygowski wrote:
On 5/20/2019 5:07 PM, jbeattie wrote:

Tom, statistically, you did not have any of your head injuries. They were imagined...

IOW: "Math is HARD!!!"



It's not math. It's statistics -- where two plus two may equal four, depending on who you are. Large population studies say little or nothing about the risks encountered by individual cyclists in particular areas or engaging in specific types of cycling. Tom is an example -- as are most of my cohorts. It doesn't take a math genius to recognize that lumping together the accident rates of NYC bike messengers and Sun City retirees is going to create a combined rate that is not accurate for either group.


Jay, that has nothing to do with your quip "Tom, statistically, you did
not have any of your head injuries."

Obviously, that's not what the statistics say. But unfortunately, there
are plenty of people who seriously engage in your logical fallacy. One
way it's been expressed is "Yes, there may be only one bike fatality per
ten million miles ridden. BUT WHAT IF THAT ONE IS _YOU_??"

And regarding large population studies: It's true that every large
population has its probability distribution, usually a bell curve. And
there are certainly individuals out on each tail end of each bell curve
- the good end and the bad end.

But that does not mean the studies say "little or nothing" about
individual risks. Unless the individual is riding his bike off the roof
of a skyscraper, his individual values are best thought of as
modifications of the mean value. One individual will very likely be
within two standard deviations of the mean. He's very unlikely to be
more than three standard deviations away from the mean. Or in other
words, almost everybody is almost average.

Above all, if a person chooses situations and behaviors that are well
within his skills and capabilities, he can place himself further on the
"good" side of that bell curve. If he takes excessive risks, he places
himself further toward the "bad" side.

An individual with a large number of crashes almost certainly didn't get
those because statistics failed. It's because one way or other, his
choices were bad.


--
- Frank Krygowski


The numbers of cyclists killed over decades is still way too small to make a good graph on. You are still stuck making generalities and theories. So these "I would have been killed were it not for my helmet" don't have any idea what they're talking about.
  #159  
Old May 29th 19, 08:32 PM posted to rec.bicycles.tech
Tom Kunich[_5_]
external usenet poster
 
Posts: 1,231
Default HOW DANGEROUS IS CYCLING? DEPENDS ON WHICH NUMBERS YOU EMPHASISE.

On Tuesday, May 21, 2019 at 7:11:03 PM UTC-7, Andre Jute wrote:
Oh dear. When did you last get anything right, Franki-boy?

On Tuesday, May 21, 2019 at 10:07:39 PM UTC+1, Frank Krygowski wrote:

An individual with a large number of crashes almost certainly didn't get
those because statistics failed.


No, no, no! Statistics don't fail. Statistics are an inanimate concept for mathematically determining from a relevant sample or compilation of cases the likelihood of a random event happening to any individual in a given universe in a particular time period. Statistics can therefore fail as little as any kind of math can fail -- ask yourself, does the math fail when a student fails to grasp Timoshenko's meaning, or is it merely the student who fails? Here, let me help you: It is not the math that fails, it is the foolish people who apply the math that fail. You give multiple samples every year, Krygowski, of really dull, commonplace ways in which the less bright among us can contaminate even simple statistics. But that never means the statistics have failed, only that you have failed to grasp what statistics can and cannot do, and because you have no relevant experience of handling statistics, you invariably go beyond what the math really describes into the bee-space in your bonnet.

It's because one way or other, his choices were bad.


No, no, no! Jesus Christ, how thick can you be? This is a novice conceptual error. Statistics are random, and have already taken into account the fact some people are accident-prone. You cannot now come and say, "Yes, but an exception must be made for the accident prone, or the drunk, or anybody I, the Great Frank Krygowski, don't like."

Then we have this prize idiocy:
But unfortunately, there
are plenty of people who seriously engage in your logical fallacy. One
way it's been expressed is "Yes, there may be only one bike fatality per
ten million miles ridden. BUT WHAT IF THAT ONE IS _YOU_??"


Once more, dear friends, into the breach of Krygowski"s endless, malignant, mindlessly stubborn stupidity. That is exactly what statistics do: they tell you a likelihood that a randomly chosen member of the cycling universe will, in the particular case under discussion here, be killed on his bicycle -- and by logical extension they tell you that you may be that random fatality. The greatest, all-embracing law in physics is that chaos prevails, that events, if you measure enough of them, are random, which for the individual biped mean they can happen to him, but Krygowski, who claims to be an engineer, doesn't understand the implications of what (if he's around 70) he was no doubt taught.

BTW, the smartest thing Krygowski ever said was his complaint that we talk only of fatalities. There are of course things a bicyclist can do to avoid becoming a statistic, but let's not pretend that his fate is entirely in his own hands when it is actually in the hands of the motorist texting his husband (see how intersectional I am? -- next Krygowski will become pregnant), the cell phone here being the deus ex machine of randomness. And do let's finish with the fatalities before we turn away to less serious injuries, because Krygowski still refuses to discuss the New York compilation of injuries and fatalities over a period of years tending* to show that between a third and half of national US bicycle fatalities can be avoided by a mandatory helmet law. That's a serious policy consideration even for a lightweight pol like Scharfie -- and it is a proper use of statistics. It leads to the frightening question: "What if you're one of the 300 odd bicyclists dying *unnecesarily* on American roads because clowns like Krygowski zealously hate helmets and abuse statistics to get their way?"

Andre Jute
The problem that all but the best engineers have with statistics is that it is an art form deceptively dressed in the outer respectability of mathematics, and so appears to be something they can understand. It isn't. For railroad minds, at best statistics is a troll, at worst a roadmap to ridicule..

* Notice the form of words I choose. This is not because I'm a weasel -- when a professional wordsmith of my experience weasels, you'll feel no pain -- but because years of thinking about the meaning of statistics in a milieu where a single mistake could cost hundreds of millions (not to mention your extremely rewarding job) powerfully inclines me to cautious spreads rather than easily attacked hard stands. You can distinguish the brainier engineers among the anti-MHL forces by their caution with the results of statistical studies -- and you can equally distinguish the incompetents and those in the grip of a beestung passion by the hard and fast rules they extract from threadbare statistics, when everyone else with the slightest experience grasps that a trend line can change direction.


Andre, please don't argue about this because I've written papers and even recently looked at the numbers to assure myself that they really haven't changed. Statistics don't fail IF you have a relevant sampling and as far as cycling deaths are concerned there are not relevant samples. Virtually every bicycle death is unique in and of itself. My study suggests that helmets have absolutely no effect but my own experience suggests that they do have an effect in minor crashes to protect the head from road rash or small blows of little consequence as long as you're wearing that piece of safety gear.

Now that Trek has engineered a new type of energy absorption foam that may be a different thing but we have no real evidence beyond test numbers and theories.

So, though I do not expect a helmet to help in any real accident I do expect them to work in minor more common ones and in fact they do work that way.
  #160  
Old May 29th 19, 08:36 PM posted to rec.bicycles.tech
Tom Kunich[_5_]
external usenet poster
 
Posts: 1,231
Default HOW DANGEROUS IS CYCLING? DEPENDS ON WHICH NUMBERS YOU EMPHASISE.

On Wednesday, May 22, 2019 at 1:49:33 PM UTC-7, jbeattie wrote:
On Tuesday, May 21, 2019 at 2:07:39 PM UTC-7, Frank Krygowski wrote:
On 5/21/2019 11:29 AM, jbeattie wrote:
On Monday, May 20, 2019 at 4:10:56 PM UTC-7, Frank Krygowski wrote:
On 5/20/2019 5:07 PM, jbeattie wrote:

Tom, statistically, you did not have any of your head injuries. They were imagined...

IOW: "Math is HARD!!!"


It's not math. It's statistics -- where two plus two may equal four, depending on who you are. Large population studies say little or nothing about the risks encountered by individual cyclists in particular areas or engaging in specific types of cycling. Tom is an example -- as are most of my cohorts. It doesn't take a math genius to recognize that lumping together the accident rates of NYC bike messengers and Sun City retirees is going to create a combined rate that is not accurate for either group.


Jay, that has nothing to do with your quip "Tom, statistically, you did
not have any of your head injuries."

Obviously, that's not what the statistics say. But unfortunately, there
are plenty of people who seriously engage in your logical fallacy. One
way it's been expressed is "Yes, there may be only one bike fatality per
ten million miles ridden. BUT WHAT IF THAT ONE IS _YOU_??"


What logical fallacy? Your statistics are so blunt, its like saying that a man has a one in 1,000 chance of getting ovarian cancer because that is the national statistic.

And regarding large population studies: It's true that every large
population has its probability distribution, usually a bell curve. And
there are certainly individuals out on each tail end of each bell curve
- the good end and the bad end.

But that does not mean the studies say "little or nothing" about
individual risks. Unless the individual is riding his bike off the roof
of a skyscraper, his individual values are best thought of as
modifications of the mean value. One individual will very likely be
within two standard deviations of the mean. He's very unlikely to be
more than three standard deviations away from the mean. Or in other
words, almost everybody is almost average.


My lifetime mileage is approaching 300,000 miles which is a multiple of standard deviations above the norm and yet you would put me in the same cohort as the once-a-year beach-bike cruiser at the local resort.

Above all, if a person chooses situations and behaviors that are well
within his skills and capabilities, he can place himself further on the
"good" side of that bell curve. If he takes excessive risks, he places
himself further toward the "bad" side.

An individual with a large number of crashes almost certainly didn't get
those because statistics failed. It's because one way or other, his
choices were bad.


Thank god you're not a doctor -- you'd ignore family history, work exposure and every other relevant factor in predicting whether a particular patient was at risk for a specific disease.

All the world is not the same, and everyone in the world is not exposed to the same risks. For example, most of the pedestrian deaths in Portland happened on a handful of roads. You are at risk crossing those roads -- more so than crossing any other roads in Portland. You're crazy to ignore the specific circumstances under which others ride, walk, sleep, garden, etc.


-- Jay Beattie.


Jay, what are you arguing about? What statistics are there on bicycle deaths that are relevant in any case above and beyond numbers of deaths per year are on the rise slower than participation of bicycling is growing?
 




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