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#11
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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
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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
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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
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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
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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
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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
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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 Ã* la culture, Ã* l’identité et aux coutumes des autres. Qu’on ne touche pas aux miennes." - Brigitte Bardot |
#18
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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
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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
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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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