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High visibility law yields no improvement in safety



 
 
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  #11  
Old March 31st 18, 03:23 AM posted to rec.bicycles.tech
Frank Krygowski[_2_]
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Posts: 7,053
Default High visibility law yields no improvement in safety

On Friday, March 30, 2018 at 8:27:21 PM UTC-4, Andre Jute wrote:

That leaves another Krygowski nothingburger. Perhaps he thought we'd read his deceptive headline and pass on without checking the article.


I thought perhaps people would read the article and we could have an intelligent
conversation. Jute, I didn't expect you to take part, since you don't qualify.

- Frank Krygowski
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  #12  
Old March 31st 18, 05:24 AM posted to rec.bicycles.tech
Andre Jute[_2_]
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Posts: 8,705
Default High visibility law yields no improvement in safety

On Saturday, March 31, 2018 at 3:23:28 AM UTC+1, Frank Krygowski wrote:
On Friday, March 30, 2018 at 8:27:21 PM UTC-4, Andre Jute wrote:

That leaves another Krygowski nothingburger. Perhaps he thought we'd read his deceptive headline and pass on without checking the article.


I thought perhaps people would read the article and we could have an intelligent
conversation. Jute, I didn't expect you to take part, since you don't qualify.

- Frank Krygowski


Oh, but we are having an intelligent conversation, Franki-boy. Its purpose is to expose your incompetent and deceitful method of conducting your war on facts you don't like.

Here you deceitful headline is again, Franki-boy: "High visibility law yields no improvement in safety". Instead of slinging limp personal insults, why don't you attempt to prove your headline is not deceitful so we can all enjoy a giggle at your floundering in another morass of your own making?

Unsigned out of contempt.
  #13  
Old March 31st 18, 05:51 AM posted to rec.bicycles.tech
Jeff Liebermann
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Posts: 2,833
Default High visibility law yields no improvement in safety

On Fri, 30 Mar 2018 12:23:13 -0400, Frank Krygowski
wrote:

https://www.bikebiz.com/news/hivis-compulsion-study


Chuckle. On the same page that the researcher reports that:
https://www.sciencedirect.com/science/article/pii/S2214140518300045
- A bicycling visibility aids law had no influence on bicycle crash.
- A bicycling visibility aids law had no influence on proportion
of bicycle crash.
- The law did not produce immediate effects, nor did it have
any effects over time.

is a link pointing to this article with the opposite conclusion:

"Randomized trials and self-reported accidents as a method to
study safety-enhancing measures for cyclists - two case studies"
https://www.sciencedirect.com/science/article/pii/S0001457517302543
A large number of studies show that high visibility in
traffic is important in the struggle of getting the attention
from other road users and thus an important safety factor.
Cyclists have a much higher risk of being killed or injured
in a traffic accident than car drivers so for them high
visibility is particularly important. A number of studies
have examined the effect of high visibility, such as
reflective clothing, but most studies have been primitive,
the data limited and the results very uncertain.
(...)
A main result from Table 4 is that there were 38% fewer
multi-party personal injury accidents in the treatment
group compared to the control group, and that the difference
is statistically significant (p 0.05).

Perhaps someone should design a reversible safety vest. One side
would be a bright and reflective color designed for maximum
visibility. The reverse site would be in some form of camouflage, for
those days when one does not feel like being a target for road rage
infected motor vehicle drivers.

--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
  #14  
Old March 31st 18, 06:04 AM posted to rec.bicycles.tech
Jeff Liebermann
external usenet poster
 
Posts: 2,833
Default High visibility law yields no improvement in safety

On Sat, 31 Mar 2018 07:19:59 +0700, John B.
wrote:

If you follow the links in the article it leads to a reference to a
study published by a Laura Thomas, described as a legal expert, that
recommends changing the law to tackle the issue of dangerous and
careless cycling that causes injury or death.


The summary of the article didn't go into much detail as to what was
actually measured. Was it hospital admissions, self-reported bicycle
accidents, police reports, insurance claims, etc?

What the author seemed to be doing is making a simple assumption. If
a law that requires wearing colors not found in nature was intended to
prevent bicycle accidents, then there should be a noticeable change in
the accident rate after the enactment of the law. The article is
hidden behind a pay-wall, so I can't offer a critique on the
methodology. However, it would be interesting to see how many
accidents are involved in the study. My guess(tm) is that the reason
there was no obvious change in the accident rate was because the
number of bicycle accidents was sufficiently small and subject to
radical variations in number, that any change precipitated by safety
clothing would disappear in the noise.

It seems to imply that a substantial number of bicycle accidents are
caused by dangerious and careless acts by the cyclist him/her self.


So, if the accident was not caused by a motorist, by default it must
have been caused by the bicyclist? Besides the cyclist, there are
plenty of other potential culprits, such as trains, airplanes, drones,
weather, road hazards, defective bicycle components, etc. High
visibility clothing isn't going to do much if you're straddling the
railroad tracks.

--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
  #15  
Old March 31st 18, 08:48 AM posted to rec.bicycles.tech
Andre Jute[_2_]
external usenet poster
 
Posts: 8,705
Default High visibility law yields no improvement in safety

On Saturday, March 31, 2018 at 6:04:48 AM UTC+1, Jeff Liebermann wrote:
My guess(tm) is that the reason
there was no obvious change in the accident rate was because the
number of bicycle accidents was sufficiently small and subject to
radical variations in number, that any change precipitated by safety
clothing would disappear in the noise.


Possible. Also possible that, for entirely random reasons, the number of bicycle accidents could be within a very narrow range over a quite substantial period. An example is nearer home to you than Italy: A few years ago, when I explained to Franki-boy that cycling in the States is actually much safer than he claimed, because he'd done the statistics incompetently, I discovered that annual bicyclist fatalities numbered for years on end in a rather narrow range around, if memory serves, around 700. The trendline was essentially flat, bearing no relationship to the growth in bicycles. In effect, even with large numbers of novice cyclists coming into the numbers every year, one had to conclude that cycling was nonetheless getting to be safer; next you would have to conclude that dedicated cycle-facilities were actually working, that night was day, and other patent foolishness. The kicker is that the numbers that caused me to perform a double-flip were actually the best available government numbers.

I have no great expectation of this Italian study proving anything more than that academics want to publish papers.
  #16  
Old March 31st 18, 09:35 AM posted to rec.bicycles.tech
John B.[_3_]
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Posts: 3,967
Default High visibility law yields no improvement in safety

On Fri, 30 Mar 2018 22:04:37 -0700, Jeff Liebermann
wrote:

On Sat, 31 Mar 2018 07:19:59 +0700, John B.
wrote:

If you follow the links in the article it leads to a reference to a
study published by a Laura Thomas, described as a legal expert, that
recommends changing the law to tackle the issue of dangerous and
careless cycling that causes injury or death.


The summary of the article didn't go into much detail as to what was
actually measured. Was it hospital admissions, self-reported bicycle
accidents, police reports, insurance claims, etc?

What the author seemed to be doing is making a simple assumption. If
a law that requires wearing colors not found in nature was intended to
prevent bicycle accidents, then there should be a noticeable change in
the accident rate after the enactment of the law. The article is
hidden behind a pay-wall, so I can't offer a critique on the
methodology. However, it would be interesting to see how many
accidents are involved in the study. My guess(tm) is that the reason
there was no obvious change in the accident rate was because the
number of bicycle accidents was sufficiently small and subject to
radical variations in number, that any change precipitated by safety
clothing would disappear in the noise.

It seems to imply that a substantial number of bicycle accidents are
caused by dangerious and careless acts by the cyclist him/her self.


So, if the accident was not caused by a motorist, by default it must
have been caused by the bicyclist? Besides the cyclist, there are
plenty of other potential culprits, such as trains, airplanes, drones,
weather, road hazards, defective bicycle components, etc. High
visibility clothing isn't going to do much if you're straddling the
railroad tracks.



A number of surveys have shown that a significant portion of bicycle
crashes are the fault of the cyclist. From memory, the CHP study in
L.A. County showed that more then 50% of the crashes, where fault
could be assessed, were the fault of the cyclist.

To determine whether colorful clothing, flashing lights, etc., are
effective the crashes caused by the cyclist's own misdeeds would have
to be factored out of the equation.

From my own observations, driving a car, cyclists with bright colored
clothing do seem to be far more noticeable then someone wearing dull
work clothes, so it seems likely that the idea that bright colors
should reduce accidents would be a commonly accepted idea.

As an aside, I once came up behind a cyclist wearing bright orange
knee socks. His orange legs going up and down were clearly visible,
and attracted attention, at a measured 300 Meters.
--
Cheers,

John B.

  #17  
Old March 31st 18, 11:38 AM posted to rec.bicycles.tech
Sepp Ruf
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Posts: 207
Default High visibility law yields no improvement in safety

Frank Krygowski wrote:

I thought perhaps people would read the article and we could have an intelligent
conversation.


Before getting effectively publishedTM, the conversation won't really take off:

https://benzinazero.wordpress.com/2017/12/20/perche-la-norma-dei-gilet-riflettenti-per-ciclisti-e-assurda-e-vessatoria/

https://www.bikeitalia.it/2018/03/28/giubbini-catarifrangenti-renderli-obbligatori-non-ha-diminuito-gli-incidenti/


Ironically, the Uni Bologna research seems to be part of
http://www.xcycle-h2020.eu/
which itself employs questionable statistical statements to sound relevant:
"Cyclists suffer a disproportionate share of serious injuries and
fatalities, and indeed in recent years that disadvantage has been growing."

(Btw, anyone who happens to attend the Vienna conference, please check if
there are ANY researchers from UBER.)

In the meanwhile, here is your chance to refresh your Italian by educating
yourself about traffic laws in Italy pertaining to cyclists:

https://www.bikeitalia.it/wp-content/uploads/2014/11/bikeitalia-codice-della-strada-e-bici.pdf

Note that lights and retroreflectors had already been obligatory:
CDS Art. 68
c)
per le segnalazioni visive: anteriormente
di luci bianche o gialle, posteriormente
di luci rosse e di catadiottri rossi;
inoltre, sui pedali devono essere
applicati catadiottri gialli ed analoghi
dispositivi devono essere applicati sui
lati.


Btw, the French introduced a similarly despotic "gilet jaune" law hampering
casual bicycle use by the diminishing proportion of secular law-abiding
inhabitants starting on 1/1/2016, and here is the provisional French
statistic of Y2016 (and Y2010) vs Y2017:

http://www.securite-routiere.gouv.fr/content/download/37631/358704/version/1/file/ONISR_Accidentalite_routiere_estimations_2017.pdf

(The big picture should include mentioning that there were over 900
bicyclist fatalities annually in the 1960's.)


--
" Je ne me suis pas battue contre l’Algérie française pour accepter une
France algérienne. Je ne touche pas * la culture, * l’identité et aux
coutumes des autres. Qu’on ne touche pas aux miennes."
- Brigitte Bardot
  #18  
Old March 31st 18, 04:34 PM posted to rec.bicycles.tech
Frank Krygowski[_4_]
external usenet poster
 
Posts: 6,167
Default High visibility law yields no improvement in safety

On 3/31/2018 6:38 AM, Sepp Ruf wrote:

Btw, the French introduced a similarly despotic "gilet jaune" law hampering
casual bicycle use by the diminishing proportion of secular law-abiding
inhabitants starting on 1/1/2016, and here is the provisional French
statistic of Y2016 (and Y2010) vs Y2017:

http://www.securite-routiere.gouv.fr/content/download/37631/358704/version/1/file/ONISR_Accidentalite_routiere_estimations_2017.pdf

(The big picture should include mentioning that there were over 900
bicyclist fatalities annually in the 1960's.)


Yes, I was aware of the French law. I wasn't aware of an attempt to pass
such a law in a U.S. state, to which Russell alluded.

This does concern me. These efforts are based, once again, on the
assumption that bicycling is so dangerous that it requires special
protective equipment. Laws like this open up possibilities for victim
blaming. Their proponents also tend to wildly overestimate the
protective effect of whatever measure they're selling. And sadly,
there's a fairly large contingent of "bicycle advocates" that are happy
to sell other cyclists up the river for failing to believe in the magic
devices.

Taken at its simplest, if the article is correct, such a law wouldn't
significantly improve safety. If enforced at all, it would certainly
dissuade a certain amount of cycling.

FWIW, I'm also against laws requiring pedestrians to carry lights or
reflectors, or forbidding them to wear dark clothing at night. The
fundamental problem is not generated by the non-motorized travelers.
It's generated by those driving motor vehicles. These laws make no more
sense to me than mandating bullet-proof vests for residents of large
American cities.

--
- Frank Krygowski
  #19  
Old March 31st 18, 05:00 PM posted to rec.bicycles.tech
Jeff Liebermann
external usenet poster
 
Posts: 2,833
Default High visibility law yields no improvement in safety

On Sat, 31 Mar 2018 00:48:29 -0700 (PDT), Andre Jute
wrote:

On Saturday, March 31, 2018 at 6:04:48 AM UTC+1, Jeff Liebermann wrote:
My guess(tm) is that the reason
there was no obvious change in the accident rate was because the
number of bicycle accidents was sufficiently small and subject to
radical variations in number, that any change precipitated by safety
clothing would disappear in the noise.


Possible.


Hard to tell, but I don't want to burn $30.50 for the report to find
out.

Also possible that, for entirely random reasons, the number of bicycle
accidents could be within a very narrow range over a quite substantial
period.


Yep. My apologies for the topic drift, but I spent some time dealing
with a similar effect when attempting to correlate the effects of cell
phone RF exposure with brain cancer. Cell phone use increased
dramatically starting in about 1995 and continues to increase today.
One might expect there to be a noticeable increase in the incidence of
new brain cancer admissions to hospitals if that were the case.

"Brain cancer incidence in SEER 9 areas of US"
https://seer.cancer.gov/faststats/selections.php?run=runit&output=1&data=1&statistic =1&year=201701&race=1&sex=1&age=1&series=cancer&ca ncer=76
Hmmm... no dramatic increase since 1995. The slight peak and decrease
is caused by the introduction of PET (positron emission tomography) to
diagnose brain cancers much earlier than before, which had the side
effect of increasing the brain cancer rate. After a while, PET scans
became the norm, the curve flattened, and the incidence rate returned
to its normal level pre-cell phone levels.

So it should be with bicycle accidents. If effective, a large number
of riders switching to high visibility clothing should produce a
corresponding decrease in accident rate. The key here is the "large
number of riders". If the statistical population sample were large, a
corresponding decrease in accidents might be considered valid.
However, if the number of riders involved were small, which implies a
rather jagged and widely varying graph of accidents vs time, then any
changes produced by a change of clothing reflectivity would be lost in
these variations (i.e. lost in the noise).

An example is nearer home to you than Italy: A few years ago, when
I explained to Franki-boy that cycling in the States is actually
much safer than he claimed, because he'd done the statistics
incompetently, I discovered that annual bicyclist fatalities
numbered for years on end in a rather narrow range around, if
memory serves, around 700. The trendline was essentially flat,
bearing no relationship to the growth in bicycles.


Yep, very much like the cell phone to brain cancer graph. According
to this site:
https://www.statista.com/statistics/227415/number-of-cyclists-and-bike-riders-usa/
there are 66 million cyclists in the USA. 700 accidents is a tiny
percentage of the bicycle riders who are eligible to becoming a
statistic (0.001%). That makes any accident survey susceptible to
huge distortions from coincidental sources, such as season, weather,
road construction, emergency medical availability, riding habits, etc.
My guess(tm) is to establish a minimum test sample of cyclists, I
would need to issue standardized reflective clothes to at least 7,000
cyclists (10%), rigorously control their use, and limit external
factors. For example, reflective clothes lose much of their
effectiveness when filthy. Issuing a reflective vest to a mountain
bike rider in winter is guaranteed to produce a dirty vest. So, 7,000
riders would be required to wash their reflective vest after every
ride. Ummm... I don't think that will work very well as most people
would simply lie and not wash the vest.

In effect, even with large numbers of novice cyclists coming
into the numbers every year, one had to conclude that cycling
was nonetheless getting to be safer; next you would have to
conclude that dedicated cycle-facilities were actually working,
that night was day, and other patent foolishness. The kicker
is that the numbers that caused me to perform a double-flip
were actually the best available government numbers.


Garbage in, garbage out. However, when obviously deficient statistics
are the only numbers available, one has to make do with what is
available. I'll take marginal numbers to bad logic, assumptions, and
guesswork any day.

Did you know that the number of bicyclists killed in collisions with
stationary objects correlates well with the number of ABA (american
bar association) lawyers?
http://tylervigen.com/view_correlation?id=6141
and the rainfall in California:
http://tylervigen.com/view_correlation?id=1490

The fallacy also works for the absence of evidence. (Absence of
evidence is not evidence of absence). An unchanged accident rate
after the introduction of mandatory reflective clothing does not mean
that reflective clothing does NOT have an effect on accident rate.
There could easily be a counter balancing effect. For example, it
might be that riders tend to ride more aggressively when wearing a
reflective vest on the assumption that the vest would protect them
from harm. At the same time, vehicle drivers would more easily notice
bicyclists. The two effects cancel each other resulting in an
unchanged accident rate.

I have no great expectation of this Italian study proving anything
more than that academics want to publish papers.


"More research and funding are necessary."
All research papers end like that.

--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
  #20  
Old March 31st 18, 05:30 PM posted to rec.bicycles.tech
Jeff Liebermann
external usenet poster
 
Posts: 2,833
Default High visibility law yields no improvement in safety

On Sat, 31 Mar 2018 15:35:51 +0700, John B.
wrote:

A number of surveys have shown that a significant portion of bicycle
crashes are the fault of the cyclist. From memory, the CHP study in
L.A. County showed that more then 50% of the crashes, where fault
could be assessed, were the fault of the cyclist.


I don't have time to chase this down to the source. Maybe later.

"Cyclists faulted most in bike-car crashes"
http://www.sandiegouniontribune.com/sdut-bicyclists-drivers-crashes-statistics-2014nov22-story.html
Only crashes between bicyclists and motorists in which
a cyclist was injured or killed were included in the 2,515
accident reports from 2011-Sept. 2014. Solo bicycle crashes,
collisions between cyclists, crashes between cyclists and
pedestrians or crashes in which fault wasn't determined
were excluded. Those types of collisions accounted for
30 percent of 3,767 bicyclist crashes.

To determine whether colorful clothing, flashing lights, etc., are
effective the crashes caused by the cyclist's own misdeeds would have
to be factored out of the equation.


In a court-o-law, the percentage of responsibility is divided up among
the various parties in order to equitably divide up the judgment. I'm
not sure, but I don't think it's done that way on California police
accident reports. It also seems to vary depending on State:
https://www.esurance.com/info/car/how-fault-is-determined-after-a-car-accident

From my own observations, driving a car, cyclists with bright colored
clothing do seem to be far more noticeable then someone wearing dull
work clothes, so it seems likely that the idea that bright colors
should reduce accidents would be a commonly accepted idea.


Yep. Visibility improves safety is one of the many assumptions made
simply because it is so difficult to conclusively prove the
connection.

As an aside, I once came up behind a cyclist wearing bright orange
knee socks. His orange legs going up and down were clearly visible,
and attracted attention, at a measured 300 Meters.


Good idea. I have two retro reflective 3M cards with clips on the
back that I fabricated. I clip them onto the back pockets of my pants
or jacket when riding. These reflectors have an odd side effect. When
drivers pass me, they often slow down more than I might expect to take
a closer look at my whatever is producing the randomly flashing
reflections.


--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
 




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