Post by: Jimbee on 11/01/2024 08:33:21
IANAScientist. But what I described above seems to be opposites. And gray is black plus white.
So what is gray?
Post by: varsigma on 11/01/2024 08:48:41
imagine a line of grey between black and white. What is the intensity of black? of white? Does the intensity of either vary along the line?
Post by: alancalverd on 11/01/2024 09:14:43
Post by: evan_au on 11/01/2024 09:47:04
- A body which reflected 100% of the light falling on it you would call "white"
- A body which reflected 0% of the light falling on it you would call "black"
https://en.wikipedia.org/wiki/Albedo#Optical_or_visual_albedo
Post by: vhfpmr on 11/01/2024 12:39:06
The Moon reflects about 14% of the light falling on it (albedo=0.14), so you could say it is grey/gray.
- A body which reflected 100% of the light falling on it you would call "white"
- A body which reflected 0% of the light falling on it you would call "black"
https://en.wikipedia.org/wiki/Albedo#Optical_or_visual_albedo
What the brain thinks is black and white is all relative:
With a TV switched off, the unlit CRT looks grey, but when it's switched on the same areas look black when they're unlit.
Photographers use an 18% grey card for exposure metering, because a surface with a reflectance of 18%, not 50% appears mid way between black & white.
Post by: evan_au on 11/01/2024 21:57:40
Quote from: vhfpmr
a reflectance of 18%, not 50% appears mid way between black & whiteFor a lot of human senses which need to span many orders of magnitude in intensity, the response tends to be logarithmic, rather than linear (linear would imply 50% is half-way).
If we call White 100% reflectance, the geometric mean of white & black is the square root of their product,
- For a geometric mean of 18%, the reflectance of "Black" would need to be around 3%
- Reasonable for a very black card in sunlight (but modern TV screens claim contrast ratios over 1000:1 - in a very dark room)
PS: I think that kids would find maths and science more relatable if we talked in units they can feel - logarithmic units
- Sound intensity is measured in dB (logarithmic), sound frequency is measured in octaves (logarithmic), brightness in astronomy is measured in magnitudes (logarithmic), and hardness is measured on Moh's scale (logarithmic except for diamond)
- I suspect that things like touch, smell and taste would also have a logarithmic response
- Psychologists have even shown that abstract concepts like "value" or "wealth" also have a logarithmic response
- The Metric System and Scientific notation are both based on a logarithmic scale
I might write up some ideas on this when I get some time...
Post by: alancalverd on 11/01/2024 22:33:07
R = 10 - log P
where P is the probability of something bad happening.
The inevitable (P = 1) has R = 10, and if R = 0 (P = 10-10) then no living person is likely to observe it.
It turns out that folk generally tolerate R ≤ 4, expect some form of statutory regulation where R > 5, and consider R > 8 to be unacceptable.
Post by: Bored chemist on 12/01/2024 13:56:34
https://www.hse.gov.uk/enforce/assets/docs/r2p2.pdf
Post by: evan_au on 12/01/2024 19:28:13
I got a Christmas present: a tear-off calendar with a brief science story for each day.
Catching up after my summer vacation, the story for January 9 was about black bird feathers.
- Apparently, some birds of paradise have "ultrablack" feathers, absorbing 99.95% of the incident light. Electron microscopy revealed feather textures which enhanced light absorption.
- However, the feathers of "normal" black birds (I assume crows and ravens) absorb only 96.8% of the incident light.
This 96.8% absorption is coincidentally close to the 3% reflectance that I guesstimated in the back-of-the-envelope calculation above for "Photographers Black".
- if "Photographers Grey" is 18% reflectance, then "Photographers Black" is (18%)2 reflectance = 3.2% reflectance = 96.8% absorption.
- After all, who takes photos of objects on Earth which are blacker than the feathers of a crow or raven?
Post by: evan_au on 12/01/2024 20:00:09
https://photo.stackexchange.com/questions/62307/why-is-18-grey-considered-to-be-in-the-middle-for-photography
I was interested to learn that the characteristic of video cameras and video monitors are calibrated for a "gamma" of 0.5.
- This means that for 8-bit video (pixel intensity range 0-255), the "middle" value of 127 corresponds to a brightness of 18% of maximum.
A speculation was that film cameras can handle exposures over about 5 f-stops (logarithmic scale). The 18% grey standard developed for film cameras is around the middle of a 5 f-stop range.
- Digital cameras can handle a slightly wider dynamic range than film cameras, and apparently some are calibrated for 12% grey (implying about 1.4% reflectance for black)
- The human eye can resolve 10-14 f-stops (with a fixed pupil size)
Post by: vhfpmr on 13/01/2024 16:42:41
For a lot of human senses which need to span many orders of magnitude in intensity, the response tends to be logarithmic, rather than linear
Any measurement that spans multiple orders of magnitude needs to be logarithmic: try designing a filter with 80dB of stopband rejection with the network analyser switched to linear, or transmitter harmonic emissions using a spectrum analyser on linear. Electronic component preferred values are a geometric progression, component tolerances are also in geometric terms (tolerances in mechanical engineering generally aren't, but you don't usually see bolt sizes in the same piece of equipment varying by orders of magnitude).
On the other hand, bicycle gears only span about 6:1, but they're also a geometric progression, they feel all wrong if they aren't.
- Psychologists have even shown that abstract concepts like "value" or "wealth" also have a logarithmic responseWhen it comes to money, people can be paradoxically geometric in their thinking when an arithmetic view is correct. It's been shown that people who would travel to get a 50% discount off a ?500 telly wouldn't travel the same distance to get a 1% discount off a ?25,000 car, even though it's the same benefit to their bank account. On the other hand, banks will round ?10.001 to ?10, but I bet they wouldn't dare try rounding ?10,001,000 to ?10,000,000
I published a note a few years ago, proposing a logarithmic scale of risk.It isn't really practical to objectively quantify risk, because risk isn't objective.
It's plain obvious that:
different people have different appetites for risk,
people will act to re-assert their chosen risk level if others attempt to change it,
people don't want zero risk (and yet virtually every risk debate starts from the premise that they do),
there's a cost-benefit analysis involved in assessing and choosing risk,
people behave more carefully when they perceive more risk,
such changes in behaviour affect the risk,
people are many times more sensitive to a risk/cost imposed upon them by others than one they choose for themselves
people are more sensitive to a risk/cost imposed on them than to the same risk/cost when they impose it on others
...and yet people will fight tooth & nail against all this, and evidence supporting it, if and when it contradicts their own behaviour.
If you include the facts that people tolerate risks that are common but don't kill many (like car crashes), rather than risks that are rare but do kill a lot of people (like plane crashes)
Cars kill ~1500 Brits a year, I don't think that many are killed by planes, what's in operation is the Availability Heuristic: people perceive probability according to how easily something springs to mind. The spectacular which gets plastered all over the media at frequent intervals is more salient than the mundane which hardly gets a mention, regardless of the true probability.
Post by: alancalverd on 13/01/2024 21:30:23
It isn't really practical to objectively quantify risk, because risk isn't objective.Oh yes it is. Risk is the product of probability x impact. In most cases involving damage to humans we can ascribe an impact value of 1 to death and turn to the insurance market for a consensus of "partial death" injury values. Thus we have credible estimates for the risk associated with exposure to ionising radiation, for instance, based on a reasonably well-founded linear or sigmoid model of impact against dose.
Interestingly (to me at least) this suggests that danger money is not illegal but actually written into law. The annual dose limit for an employee, i.e. someone whose income depends on occupational exposure, is 20 times that for a member of the public, and we can assign emergency levels up to 5 times that for a single exposure incurred in attempting to save life.
There is a significant difference between objective risk, on which we base engineering decisions, and perceived risk, that determines customer behavior. You could drive a tank and be reasonably certain of surviving any collision - even with another tank - but it would make a mess of the road, burn lots of fuel, and be limited to about 45 mph, so most folk drive something with a finite NCAP squashability rating rather than 30 tons of armor.
I dispute BC's suggestion that people "tolerate" car crashes but not plane crashes. Neither driving nor flying is banned (which would be the case if either were intolerable) but both are subject to regulation and the survivors complain like mad in the event of a collision. In an average year I fly about as far as I drive and find aviation far more tolerable (no traffic jams, no road works, no pedestrians, very few idiots changing lane without signalling) and studiously try to avoid crashing either vehicle.
Anyway, 1500 UK road deaths per year gives us an annual risk index (see reply #6 above) R = 5.3, the level at which I suggested people expect some degree of statutory regulation, which we have. My index coincides pretty well with the will of Parliament and the attitudes of rational people.
Post by: evan_au on 13/01/2024 21:37:19
Quote from: vhfpmr
people behave more carefully when they perceive more risk,Apparently, after cyclones were given both male & female names (back in 1975), it was discovered that female-named cyclones killed more people than male-named cyclones. ("Cyclone" is Australian for hurricane.)
- I saw a speculation this week that female-named cyclones were perceived as less threatening than males, and so people took fewer precautions!
- Of course, if we went the next step and started giving cyclones names from multiple languages, that effect would disappear - and perhaps we may see racism in cyclone deaths? Names in languages that were perceived as more threatening might kill fewer people?
This came up in the context of heat waves - apparently Spain & Portugal have started naming heat waves
- It has been claimed that heat waves have killed more people in Australia than all other natural disasters combined (since modern records began)
- A week ago, I noticed the Bureau Of Meteorology* starting to quote "Dew Point" in weather reports. They said that with a dew point above 24C, some people will start to suffer heat stress (especially the elderly and the young). And that day had a dewpoint of 24C.
*The obvious (and common) nickname for the Australian Bureau Of Meteorology is "BOM" (pronounced "bomb"). Last year they came out with a press release stating that they were only to be called the Bureau Of Meteorology, and never "BOM"... Maybe people had realised that they were dropping too many climate bombshells, after they had to add an extra colour to the weather maps to denote extreme temperatures (purple is higher than red or black).
Australia_Heat_map.png (429.45 kB . 966x606 - viewed 600 times)http://www.bom.gov.au/australia/charts/viewer/index.shtml?type=T&level=2m&tz=AEDT&area=Au&model=CG&chartSubmit=Refresh+View
Post by: alancalverd on 13/01/2024 21:43:31
Post by: Bored chemist on 13/01/2024 22:45:36
I dispute BC's suggestion that people "tolerate" car crashes but not plane crashes. Neither driving nor flying is banned (which would be the case if either were intolerable)They plainly tolerate car crashes so I presume you agree with me on that.
But the electorate has (indirectly) insisted on much more stringent regulations for aircraft safety- to the point where plane deaths are much rarer by most measures (maybe all).
So they are clearly less tolerant of plane crash deaths.
Which was the point.
And, if you look at what I said "if you include the facts that people tolerate risks that are common but don't kill many (like car crashes), rather than risks that are rare but do kill a lot of people (like plan crashes)", you will see I was saying that they have a preference "They tolerate A rather than B".
I could have made it clearer but I figured the audience here was bright enough to understand. It looks like most were.
Post by: Bored chemist on 13/01/2024 22:53:56
Cars kill ~1500 Brits a year, I don't think that many are killed by planes, what's in operation is the Availability Heuristic: people perceive probability according to how easily something springs to mind.I know more people who have been in car crashes than have been in plane crashes.
So the "availability" argument isn't convincing.
If anything, it's the other way round. The newspapers etc publish stories about 10 people dying in a plane crash but not about the 25 killed on the road each month precisely because people are more interested in rare events involving a moderately large number than in the thing which kills a lot more people, but by a steady drip feed of corpses.
I'm told most drivers think they are "better than average" so they aren't so concerned about risks from their own driving.
(If I really wanted to cause an argument, I'd make the point that gun owners think that "their gun" keeps them safe, but "everybody else's gun" is a threat).
The big reason are less scared of car travel than plane travel is related to the perception of control.
People don't think they will crash their own car. Every year about 1500 find out (briefly) that they are wrong.
Post by: evan_au on 14/01/2024 11:13:06
https://www.thenakedscientists.com/forum/index.php?topic=86692.0
All comments are welcome!
Post by: alancalverd on 14/01/2024 17:20:58
They plainly tolerate car crashes so I presume you agree with me on that.I have never met anyone (outside of a banger race track) who found a car crash tolerable. Most people try to avoid them, but acknowledge their own and others' fallibility. Being a bit of a pedant, I can differentiate between tolerating something, like a smelly but friendly dog, and acknowledging the inevitability of something wholly unpleasant, like death and taxes.
I'm not convinced that air travel is more stringently regulated than road transport. The standard passenger lap belt on a plane would not pass an MoT inspection.
Post by: alancalverd on 14/01/2024 17:30:14
(If I really wanted to cause an argument, I'd make the point that gun owners think that "their gun" keeps them safe, but "everybody else's gun" is a threat).I recall a sensible American student being interviewed after what has become a routine classroom slaughter. Interviewer (Fox News) asked why he didn't carry a gun for self-protection. He said "If the police turn up and see me holding a gun, they will shoot me."
Post by: Petrochemicals on 14/01/2024 20:09:03
"In the event of a head on smash.............."
I'm not convinced that air travel is more stringently regulated than road transport. The standard passenger lap belt on a plane would not pass an MoT inspection.
Post by: alancalverd on 15/01/2024 11:42:53
Not that seat belts make much difference in civil aviation. Many people unbuckle them as soon as the wheels touch the ground, that is, when entering the phase of the journey most likely to incur sudden braking or collision. There's a lot of air upstairs, and very few aircraft, mostly 5 miles apart, but taxiways are narrow and occupied by all sorts of traffic.
It's a known fact that your IQ drops by 10 points whenever you sit in the pilot's seat, but the behavior of passengers, particularly on budget airlines, is utterly baffling. Your ticket says "one carry-on bag", but at least 20% of passengers are unable to count up to 1. Why do people stand in a queue for an hour before boarding, if they have assigned seats? Why do they pay for "priority boarding", which means waiting in another queue at the bottom of the stairs? Why do they stand up as soon as the plane stops moving, fight to encumber themselves with their precious one bag, then hang around in the aisle waiting for the doors to open?
Post by: Petrochemicals on 15/01/2024 17:31:25
.it does not prevent damage to the head and neck. Military transports have the passenger seats facing backwards - much, much safer.The same could be said of most coach seats, they are only lap straps after row 1, i suppose the thinking is that you only need 3 point or more protection if you are somewhere near the front, plus complicated harnesses may hinder the evacuation process.
Funily enough the back of the head and neck injuries are not the things that seatbelts protect from, and probably create more of that sort. Seat belts prevent you from smashing your frontal cortex on the windscreen and dying, or maybe the rear passengers flying through the windscreen face first, the fact that the neck and head are not supported mean that they continue and recieve whiplash. The way to prevent this is as they do in formula one, a helmet with an attachment point at the rear of it, it maybe something the AA should think about bringing in, after all a 500mph head on smash will no doubt lead to whiplash claims. But again this may hinder the evacuation efforts from a flaming winged petrol can.
Post by: Petrochemicals on 15/01/2024 17:32:27
Post by: alancalverd on 16/01/2024 10:16:20
Post by: alancalverd on 16/01/2024 10:19:56
What is white? If you shine an intense enough light on grey does it become white?It becomes whiter. "White" is very much a matter of perception, which is why detergent manufacturers include blue specks in their product to modify the spectrum emitted from nominally white materials.
Post by: Bored chemist on 17/01/2024 10:41:38
An American elephant.
Or, given the spelling.
https://en.wikipedia.org/wiki/Louis_Harold_Gray
Post by: alancalverd on 17/01/2024 11:54:33
Post by: vhfpmr on 19/01/2024 16:07:21
The impact to you might depend on whether you have comprehensive insurance, that will affect your aversion, that will affect your behaviour, and that will affect probability. Risk isn't objective.It isn't really practical to objectively quantify risk, because risk isn't objective.Oh yes it is. Risk is the product of probability x impact.
Give someone a seatbelt and they drive faster, which is largely why the projected benefits calculated from 'objective' risk never materialised.
Give cyclists crash helmets, and they end up with 30% more limb & torso injuries.
In most cases involving damage to humans we can ascribe an impact value of 1 to death and turn to the insurance market for a consensus of "partial death" injury values.So you think that the insurance industry knows the value of your arm better than you do? Value to who, you or the economy? Which of those most affects your own behaviour?
Quote from: vhfpmrpeople behave more carefully when they perceive more risk,Apparently, after cyclones were given both male & female names (back in 1975), it was discovered that female-named cyclones killed more people than male-named cyclones. ("Cyclone" is Australian for hurricane.)
- I saw a speculation this week that female-named cyclones were perceived as less threatening than males, and so people took fewer precautions!
;D Variously known as Risk Compensation, Risk Homeostasis, and in the insurance industry, Moral Hazard. I like that one, I'd not seen that before.
Plane crashes are more available becauseCars kill ~1500 Brits a year, I don't think that many are killed by planes, what's in operation is the Availability Heuristic: people perceive probability according to how easily something springs to mind.I know more people who have been in car crashes than have been in plane crashes.
So the "availability" argument isn't convincing.
newspapers etc publish stories about 10 people dying in a plane crash but not about the 25 killed on the road each month precisely because people are more interested in rare events involving a moderately large number than in the thing which kills a lot more people, but by a steady drip feed of corpses.Wave the plane crashes in their faces every verse end, and that's what people will notice.
Seat belts prevent you from smashing your frontal cortex on the windscreenBut not on the steering wheel.
Post by: alancalverd on 19/01/2024 17:22:49
So you think that the insurance industry knows the value of your arm better than you do?Any insurance policy is a negotiated contract.
You decide how much your arm is worth: the insurer estimates how likely you are to lose it (i.e. the risk: probabiity x impact), and offers you a premium to cover that amount. There are some standard policies that represent previous court settlements for injury to Joe Average, the cost of motor vehicle repairs, house fires, etc but an athlete or a musician might require a higher figure for certain personal injuries.
Post by: Petrochemicals on 19/01/2024 20:29:30
Give someone a seatbelt and they drive faster, which is largely why the projected benefits calculated from 'objective' risk never materialisedNonsense, most people drive in a way to prevent damage to their car, seat belt or no, the idea of imminent demise is not really a thought. Seatbelts save lives.
But not on the steering wheelyes even on the steering wheel.
Post by: Bored chemist on 20/01/2024 00:19:08
Nonsense, most people drive in a way to prevent damage to their car, seat belt or no, the idea of imminent demise is not really a thought. Seatbelts save lives.OK imagine that one day you are asked to drive to a meeting across town. They give you an armoured truck to make the trip.
Then, the next day, for the same trip, they give you a rickety old schoolbus which has a bottle of nitro-glycerine on the next seat and dodgy suspension.
Do you drive the same way in both cases, or do you adjust your driving according to the apparent risk?
Anyway, here's some data. from
https://en.wikipedia.org/wiki/Reported_Road_Casualties_Great_Britain
Seat belt death.png (118.79 kB . 1024x650 - viewed 679 times)
Post by: evan_au on 20/01/2024 05:56:55
- He wrote a paper arguing that road safety measures weren't worth the cost, because they didn't save any lives.
- Apparently, the numbers in Peltzman's paper were later found to be in error;
- Subsequent work suggests that the gain from some safety measure is up to half offset by more risky behaviours (the comment about bicycle helmets suggests a 30% offset).
Maybe Peltzman was more worried about the effect on purchase price than the effect on human life?
https://en.wikipedia.org/wiki/Risk_compensation
Post by: Bored chemist on 20/01/2024 12:44:57
Previously, people didn't even try to work in "gassy" mines.
With the lamp, they could do so.
And when a pickaxe struck a spark...
Post by: Petrochemicals on 21/01/2024 16:55:52
- Subsequent work suggests that the gain from some safety measure is up to half offset by more risky behaviours (the comment about bicycle helmets suggests a 30% offset).Any correlation in a graph between road deaths and seat belts is highly dilute. For example it can be refuted by the following graaphs
Screenshot_20240121_165734_com.android.chrome~2.jpg (131.19 kB . 1920x1131 - viewed 211 times)car ownership Screenshot_20240121_165707_com.android.chrome~2.jpg (192.5 kB . 1920x1137 - viewed 203 times)bicycle ownershipAs you can seeevwn though car ownership goes up, road deaths come down with the drop in bycycle ownership.
Post by: vhfpmr on 22/01/2024 15:28:08
So how much will you sell me your arm for then? Mine aren't for sale.So you think that the insurance industry knows the value of your arm better than you do?You decide how much your arm is worth
Janssen at the Dutch transport research labs says otherwise, because unlike you, he's done the research.Give someone a seatbelt and they drive faster, which is largely why the projected benefits calculated from 'objective' risk never materialisedNonsense, most people drive in a way to prevent damage to their car, seat belt or no,
Quote
the idea of imminent demise is not really a thoughtYour conception of risk compensation is utterly naive, almost all of the behaviour is completely subconscious. All it takes to wipe out the benefit of seat belts is one extra death every few million miles travelled, no single individual even has that amount of personal experience, let alone the ability to perceive it.
Quote
Seatbelts save lives.Professor John Adams at UCL is the guy who did all the research into seatbelts for the government prior to their being made compulsory. He found that nowhere in the world had been able to demonstrate a reduction in road deaths attributable to the introduction of compulsory seat belt legislation. His work was peer reviewed by the DoT, but HMG chose to ignore it, and legislate anyway. The initial legislation was for a temporary trial period, during which time the DoT report was leaked to New Scientist, but the HMG and society in general still ignored it, and so the law became permanent.
But not on the steering wheel
Quote
yes even on the steering wheel.The piece of my nose bone that I dug out of the steering wheel in this says otherwise:
TR7 #2.jpg (44.79 kB . 466x322 - viewed 176 times)As I said above, virtually all of risk compensation is stark staring obvious, and yet people will fight tooth & nail against it when it contradicts their own vested interests.
It's sometimes called the Peltzman Effect, named after a Chicago economics professor.It's more complicated than that, because the probability of changing your behaviour will depend on your perception of the effectiveness of the safety device. Paradoxically, that means those most likely to benefit from a helmet are the ones who think it's least effective.
- He wrote a paper arguing that road safety measures weren't worth the cost, because they didn't save any lives.
The immediate effect of teh introduction of Davy's safety lamp was an increase in mine explosions.Yup, John Adams cites this example of risk compensation.
Previously, people didn't even try to work in "gassy" mines.
With the lamp, they could do so.
And when a pickaxe struck a spark...
Another interesting one is that motorists who cycle are half as likely to crash their cars than ones who don't.
Why? Because they see the roads from both sides of a car windscreen and experience the treatment meted out to cyclists first hand, and so have an entirely different perception of the risk on the roads. Cyclists can even get a discount off their car insurance.
83% of cyclists drive, and know what they're talking about, 70% of motorists don't cycle, and from years of arguing with them on Twitter I can say they generally talk out of their bums.
Walk a mile in another's shoes, and all that.
car ownership goes up, road deaths come downIt's been known for decades that road deaths correlate with traffic density, not safety devices: busy roads look more dangerous, so people drive more carefully on them.
Post by: Petrochemicals on 22/01/2024 15:42:33
The piece of my nose bone that I dug out of the steering wheel in this says otherwiseYou where alive to dig it out.
Post by: Petrochemicals on 22/01/2024 15:48:10
It's been known for decades that road deaths correlate with traffic density, not safety devices: busy roads look more dangerous, so people drive more carefully on themUnless they have seatbelts, as such they start screaming around like a stock car racer with a death wish?
Post by: alancalverd on 22/01/2024 17:59:44
Another interesting one is that motorists who cycle are half as likely to crash their cars than ones who don't.
Why?
Because most road accidents occur within 5 miles of the home of one of the drivers. If you have a bike, you are less likely to use the car for short journeys!
Post by: alancalverd on 22/01/2024 18:04:32
So how much will you sell me your arm for then? Mine aren't for sale.
Standard compensation claim for one arm (solicitors' guidance)
Quote
Above the elbow, GBP102,890 -122,860, below the Elbow GBP90,250 - 102,890More for younger people. Self-employed would probably choose 2 - 5 times that level of insurance.
Post by: evan_au on 23/01/2024 09:48:44
Quote from: OP
What Is Gray?I heard there are 50 shades of Gray...
Post by: vhfpmr on 26/01/2024 16:30:39
Indeed, but proof that a seatbelt saved my life doesn't constitute proof that seatbelts reduced the total deaths on the roads.The piece of my nose bone that I dug out of the steering wheel in this says otherwiseYou where alive to dig it out.
After seatbelts were introduced, deaths among pedestrians went up by 8-20%, cyclists 13-40%, and rear seat passengers (who had no belt compulsion), 27%. When rear seatbelts were made compulsory for children, deaths among children in rear seats went up by 10%.
All it took to negate the benefits of seatbelts was one extra death every 200,000,000 kilometres, that's hardly what I'd call screaming around like a stock car racer with a death wish. Germany enshrined risk compensation in law by increasing the maximum permitted speed for coaches fitted with seatbelts from 80km/h to 100km/h.It's been known for decades that road deaths correlate with traffic density, not safety devices: busy roads look more dangerous, so people drive more carefully on themUnless they have seatbelts, as such they start screaming around like a stock car racer with a death wish?
Perhaps, but the Dutch are famous for cycling a lot, and they drive as many miles as we do.Another interesting one is that motorists who cycle are half as likely to crash their cars than ones who don't.Because most road accidents occur within 5 miles of the home of one of the drivers. If you have a bike, you are less likely to use the car for short journeys!
Why?
I don't think there are many other than you who would forfeit a good arm for ?123,000, or even ?1,230,000, and particularly not just because a solicitor has told them that's what it's worth.So how much will you sell me your arm for then? Mine aren't for sale.
Standard compensation claim for one arm (solicitors' guidance)QuoteAbove the elbow, GBP102,890 -122,860, below the Elbow GBP90,250 - 102,890More for younger people. Self-employed would probably choose 2 - 5 times that level of insurance.
Post by: alancalverd on 26/01/2024 17:54:32
Perhaps, but the Dutch are famous for cycling a lot, and they drive as many miles as we do.Partial statistics aren't terribly helpful.
I don't think there are many other than you who would forfeit a good arm for ?123,000, or even ?1,230,000, and particularly not just because a solicitor has told them that's what it's worth.Nobody is talking about voluntary trade here, nor the "worth" of a limb. The solicitors' numbers represent average awards decided by the courts, and are therefore the starting point for most insurance policies in the UK. The absence of free rehabilitation services in banana republics like the USA leads to much higher settlements, and as I said, if you want to insure anything for more that the standard offer, you can negotiate with the insurer. As an example, if you hire a small mobile crane, the industry standard insurance cover written in large print on every page is GBP25,000 per lift, which will pay for a lot of bricks and even repairing the car that they fell on. My brilliant company secretary ignored the "ask for more if you need it" warning and contracted at standard rate for lifting a GBP500,000 MRI machine which, by the immutable laws of physics, they managed to drop from a considerable height. A veritable harvest for the lawyers and scrap merchants.
Post by: vhfpmr on 26/01/2024 19:45:04
That's precisely what we're talking about, the voluntary decision whether to get in a car, or go rock climbing, and the subjective evaluation of the personal benefit of that activity against the cost of being maimed. Neither a solicitor nor a mathematician can tell you how much you're going to enjoy climbing, or how much you're going to dislike losing an arm. The best they could do is inform you with the odds.I don't think there are many other than you who would forfeit a good arm for ?123,000, or even ?1,230,000, and particularly not just because a solicitor has told them that's what it's worth.Nobody is talking about voluntary trade here, nor the "worth" of a limb.
The solicitors' numbers represent average awards decided by the courts, and are therefore the starting point for most insurance policies in the UK. The absence of free rehabilitation services in banana republics like the USA leads to much higher settlements, and as I said, if you want to insure anything for more that the standard offer, you can negotiate with the insurer.This is all irrelevant, it's about the cost of providing disability aids after you've already lost your arm, and aren't getting it back again.
Post by: Petrochemicals on 26/01/2024 21:35:11
After seatbelts were introduced, deaths among pedestrians went up by 8-20%, cyclists 13-40%, and rear seat passengers (who had no belt compulsion), 27%. When rear seatbelts were made compulsory for children, deaths among children in rear seats went up by 10%.Is this not ambiguous? Afer seatbelts where introduced when? until now? Car ownership has gone up a gazillion times in a century. A statement could read
"before seatbelts the country had a far higher death rate on the roads, even though car ownership was a fraction of what it is today"
Even though true, it is about as contextual as your statement
Indeed, but proof that a seatbelt saved my life doesn't constitute proof that seatbelts reduced the total deaths on the roads.I would say that it does.
that's hardly what I'd call screaming around like a stock car racer with a death wish.They either drive more responsibly or they drive more recklessly, (or perhaps there are other reasons.
Post by: vhfpmr on 27/01/2024 14:04:52
Comparison is with the period immediately before belts to that immediately after, and as I've already said, the accident rate goes down not up when traffic density increases.After seatbelts were introduced, deaths among pedestrians went up by 8-20%, cyclists 13-40%, and rear seat passengers (who had no belt compulsion), 27%. When rear seatbelts were made compulsory for children, deaths among children in rear seats went up by 10%.Is this not ambiguous? Afer seatbelts where introduced when? until now? Car ownership has gone up a gazillion times in a century. A statement could read
"before seatbelts the country had a far higher death rate on the roads, even though car ownership was a fraction of what it is today"
Even though true, it is about as contextual as your statement
Well it patently doesn't, does it. How do you know that I would still have had that accident if I'd not been wearing a seatbelt? To prove the case you have to demonstrate that there are fewer deaths with seatbelts, not just cherry-pick one example of a crash.Indeed, but proof that a seatbelt saved my life doesn't constitute proof that seatbelts reduced the total deaths on the roads.I would say that it does.
You need to count:
1. Those who survive because they are wearing a belt
2. Those who die because they're not wearing a belt
3. Those who survive because they're not wearing a belt
4. Those who die because they are wearing a belt
Reckless: Heedless of or indifferent to the consequences of one's actions; lacking in prudence or caution; willing or liable to take risks; rash, foolhardy; irresponsible. (OED)that's hardly what I'd call screaming around like a stock car racer with a death wish.They either drive more responsibly or they drive more recklessly, (or perhaps there are other reasons.
If someone is likely completely unaware their behaviour has changed, and witnesses are equally unaware, I think you'd be hard pressed to describe it as reckless as defined in the OED (you are free to make up your own definitions of words, however, if you like being misunderstood). As I said above one extra death per 200,000,000km is too small for any single individual to perceive in the behaviour of themselves or others, it takes statistical analysis.
It does offer ample opportunity for society to be systematically obtuse, however.
Post by: vhfpmr on 27/01/2024 15:14:40
a rickety old schoolbus which has a bottle of nitro-glycerine on the next seat and dodgy suspension.You've been watching Wages of Fear
Anyway, here's some data. fromAdams can do a bit better than that, the cohorts in this graph contain 80% of all the world's motor traffic:
https://en.wikipedia.org/wiki/Reported_Road_Casualties_Great_Britain
Fig 7.1 World.png (79.15 kB . 682x702 - viewed 159 times)Note how deaths in the no-law group fall faster than the deaths in the group with compulsory belts, and how the fall in deaths doesn't coincide with the introduction of legislation.
This plot shows Denmark's experience of seatbelt legislation compared against the countries with no law:
Fig 7.2 Denmark.png (56.75 kB . 691x654 - viewed 161 times)From Adams:
"Doubt was first cast on the international evidence for seat belt laws in a paper of mine in 1981 (Adams 1981); Figures 7.1 to 7.4 above were first published in this paper. Britain?s Department of Transport commissioned an internal critique of my paper. This critique, entitled Seat belt savings: implications of European statistics (Isles 1981), concluded that there was no foundation for the Department?s oft-repeated claim that a seat belt law would save 1,000 lives and 10,000 injuries a year. It found what I had discovered, and what Evans found ten years later in his review of the evidence worldwide?that there were no directly measurable reductions in fatalities that could be attributed to seat belt laws. It said
'Available data for eight western European countries which introduced a seat belt law between 1973 and 1976 suggests that it has not led to a detectable change in road deaths [my emphasis]?The results are not compatible with the Department?s ?1,000 plus 10,000? estimates?'
The author of this report was aware of the risk compensation hypothesis, and hence aware that evidence concerning the effectiveness of seat belts in crashes did not constitute satisfactory evidence about the likely effect of a law compelling people to belt up. He insisted that ?international comparisons provide the only information about the effect of compulsory seat belt wearing, both on car occupants and on other road users?. Furthermore, this report also noted that in all eight countries, as in Australia, the number of pedestrians injured following the passage of a seat belt law increased. Individually, none of the increases was statistically significant, but collectively this result was highly significant."
Post by: alancalverd on 27/01/2024 15:52:36
in all eight countries, as in Australia, the number of pedestrians injured following the passage of a seat belt law increased.which suggests that wnen car occupants wear seatbelts, more pedestrians wander into the road.
Unexpected, and therefore worth investigating.
Post by: Petrochemicals on 27/01/2024 16:05:28
Comparison is with the period immediately before belts to that immediately after, and as I've already said, the accident rate goes down not up when traffic density increases1)which is the immediate period.
2)impossible, density 0 = no accidents because of no flow . Density = 100 no accidents because of no flow This is road traffic science.
https://en.m.wikipedia.org/wiki/Reckless_driving
So given a seat belt do most drivers irresonsibly start hareing around? Or are drivers responsible?
Post by: alancalverd on 27/01/2024 23:29:23
Suppose in Country A we had a fatality rate of 1000 per million population in 1973, and it decreased to 800 per million in 1977. Normalise to 1973 = 100 and you have the "no law" curve for graph 7.1 above.
Now suppose Country B had a fatality rate of 100 per million in 1973, falling to 85 per million in 1977. There's the curve for "law".
By normalising, we have made the country with around 10 times the fatality rate look "safer"! Next thing you know, we'll be declaring Rwanda a safer place than France because the UK only granted asylum to 8 Rwandans fleeing persecution last year, and 15,000 to folk who arrived from Europe.
Post by: Petrochemicals on 28/01/2024 16:23:44
https://en.m.wikipedia.org/wiki/1973_oil_crisis
Post by: vhfpmr on 28/01/2024 18:12:16
The reason more die is because motorists aren't driving as carefully, the same reason that more children died in back seats after they were made to wear seatbelts. Or are you going to suggest that children wearing seat belts are more likely to wander in front of the car?in all eight countries, as in Australia, the number of pedestrians injured following the passage of a seat belt law increased.which suggests that wnen car occupants wear seatbelts, more pedestrians wander into the road.
In the case of children in back seats, the year before children's seatbelts (1988) to the year after (1990). Pedestrians & cyclists, dates will vary by country. The seatbelt law didn't apply to HGVs when it was first introduced, so pedestrians and cyclists killed by HGVs went down, and not up like those killed by cars.Comparison is with the period immediately before belts to that immediately after, and as I've already said, the accident rate goes down not up when traffic density increases1)which is the immediate period.
2)impossible, density 0 = no accidents because of no flow . Density = 100 no accidents because of no flow This is road traffic science.
You can make a nonsense of any data if you extrapolate it beyond the bounds of common sense.
Smeed Annotated.JPG (87.46 kB . 1124x789 - viewed 161 times)https://en.m.wikipedia.org/wiki/Reckless_drivingSo we've now established they aren't driving recklessly by either the OED definition of the word, or the US Legal definition. So why are we arguing about what you call it at all? It's kafkaesque, like watching someone get stabbed and then starting an argument about whether the weapon's called a knife or a dagger. Drivers have more accidents when they belt up. Too few more for any one individual to be able to detect in their lifetime, but enough to negate the effect of seatbelts.
So given a seat belt do most drivers irresonsibly start hareing around? Or are drivers responsible?
The graphs are a fine example of really bad statistics.
Suppose in Country A we had a fatality rate of 1000 per million population in 1973, and it decreased to 800 per million in 1977. Normalise to 1973 = 100 and you have the "no law" curve for graph 7.1 above.
Now suppose Country B had a fatality rate of 100 per million in 1973, falling to 85 per million in 1977. There's the curve for "law".
By normalising, we have made the country with around 10 times the fatality rate look "safer"! Next thing you know, we'll be declaring Rwanda a safer place than France because the UK only granted asylum to 8 Rwandans fleeing persecution last year, and 15,000 to folk who arrived from Europe.
I don't see what you're getting at, if you don't normalise the effect of belts to the number of deaths that could potentially be saved you get nonsense. It could end up being like arguing that a vaccine that prevents 10% of a million deaths is better than one that prevents 90% of 1000.
Law countries reduced their deaths ~15% over the same period that no-law countries reduced their deaths ~20%.
Post by: vhfpmr on 28/01/2024 18:18:14
https://en.m.wikipedia.org/wiki/1973_oil_crisis
Yes of course, the oil crisis only picked on the countries that introduced compulsory seat belts and left all the others alone didn't it. Silly me.
Post by: Petrochemicals on 28/01/2024 23:11:27
Yes of course, the oil crisis only picked on the countries that introduced compulsory seat belts and left all the others alone didn't it. Silly me.Well surely the scarcity of petrol has an effect. It was an example as to the factors that are not represented on the graph. For example cars increace so do road deaths actually go down or is there more opportunity? The increace in road deaths correlates with the ammount of 2nd cars, used probably at this point in history by married women who where house wives during the day.
Post by: Petrochemicals on 28/01/2024 23:31:19
In the case of children in back seats, the year before children's seatbelts (1988) to the year after (1990).But uk road deaths show a very steady deline from 1990 onwards? Not withstanding that children have a tendancty to catapult out of adult seatbelts, i think this is why childrens booster seat where introduced.
You can make a nonsense of any data if you extrapolate it beyond the bounds of common sense.
Relationship-of-speed-volume-density-LOS-and-total-crash-rates.png (210.28 kB . 850x525 - viewed 174 times)So we've now established they aren't driving recklessly by either the OED definition of the word, or the US Legal definition. So why are we arguing about what you call it at all?Because given a seatbelt drivers according to you start being more reckless. Or do reckless drivers not cause road deaths?
Post by: vhfpmr on 30/01/2024 19:32:59
Petrol use was the same for both the law & no law cohorts, the difference between them is the seatbelt law. I can't make any sense of the rest of your post. Death rates have shown an accurate correlation with traffic density in almost every country it's been measured over decades, but not to other confounding variables.Yes of course, the oil crisis only picked on the countries that introduced compulsory seat belts and left all the others alone didn't it. Silly me.Well surely the scarcity of petrol has an effect. It was an example as to the factors that are not represented on the graph. For example cars increace so do road deaths actually go down or is there more opportunity? The increace in road deaths correlates with the ammount of 2nd cars, used probably at this point in history by married women who where house wives during the day.
Post by: vhfpmr on 30/01/2024 19:50:38
But uk road deaths show a very steady deline from 1990 onwards?Yes, because traffic density is increasing.
Not withstanding that children have a tendancy to catapult out of adult seatbelts, i think this is why childrens booster seat where introduced.So children bounce around inside the car more when they're belted than when they aren't? I don't think so.
This means nothing without any explanation of what it relates to, and what its relevance is supposed to be.
Because given a seatbelt drivers according to you start being more reckless. Or do reckless drivers not cause road deaths?Again:
The difference in behaviour required to negate the benefit of seatbelts is one death in 200,000,000 km, that's too small for any individual to detect without statistical analysis. Whether you choose to call it reckless is irrelevant, but by the OED definition of reckless, it's not.
This just falls on deaf ears, doesn't it.
You are just playing games with words, describing it as reckless knowing that people won't perceive it as such, and hoping that they'll conclude from that that you have successfully refuted the argument, and that if they can't see behaviour change with their own eyes it doesn't exist.
Post by: vhfpmr on 30/01/2024 19:56:49
Smeeds Law (http://john-adams.co.uk/wp-content/uploads/2006/smeed%27s%20law.pdf)
Risk (http://www.john-adams.co.uk/wp-content/uploads/2017/01/RISK-BOOK.pdf)
More (http://john-adams.co.uk/wp-content/uploads/2007/10/risk%20and%20freedom.pdf) on Smeed (Chapter 2)
Post by: Petrochemicals on 30/01/2024 20:42:04
Yes, because traffic density is increasing.But then levels off?. The decline before seat belts to after
In the case of children in back seats, the year before children's seatbelts (1988) to the year after (1990).I'm afraid you argue against your own earlier point.
So children bounce around inside the car more when they're belted than when they aren't? I don't think soNo that would be the decline in road deaths after child booster seats were introduced.
This means nothing without any explanation of what it relates to, and what its relevance is supposed to be.Flow increases, speed decreases, density increaces, crashes increaces. Density increaces accidents.
Again:So if it is undetectable we can not make statements about seatbelts creating reckless deathwish drivers.
The difference in behaviour required to negate the benefit of seatbelts is one death in 200,000,000 km, that's too small for any individual to detect without statistical analysis.
Whether you choose to call it reckless is irrelevant, but by the OED definition of reckless, it's not.Reckless drivers do not cause deaths then, nor deaths by dangerous driving cause deaths either, amazing! And playing with words, mmm them difficult words. Causing problems in arguments.
This just falls on deaf ears, doesn't it.
You are just playing games with words.
describing it as reckless knowing that people won't perceive it as such,Well this is clear codswallop, using words in the hope people don't think the words mean what they mean?
Post by: alancalverd on 03/02/2024 09:05:17
which suggests that wnen car occupants wear seatbelts, more pedestrians wander into the road.Part of seatbelt legislation often requires children to be in the back seat, so some of those who would have died in the front seat now die in the back seat. And as far as I know, pedestrians are not defined as persons wearing seatbelts.
The reason more die is because motorists aren't driving as carefully, the same reason that more children died in back seats after they were made to wear seatbelts. Or are you going to suggest that children wearing seat belts are more likely to wander in front of the car?
Post by: vhfpmr on 03/02/2024 15:28:02
children have a tendancty to catapult out of adult seatbelts, i think this is why childrens booster seat where introduced
the decline in road deaths after child booster seats were introducedI know why booster seats were introduced, you haven't produced any evidence that children's seat belts reduced road deaths.
Flow increases, speed decreases, density increaces, crashes increaces. Density increaces accidents.Irrelevant. Smeed's Law has nothing to do with short term variations in flow rate, it relates to long term variation in the number of vehicles per head of population.
So if it is undetectable we can not make statements about seatbelts creating reckless deathwish drivers.It isn't undetectable, and drivers aren't being reckless.
DON'T PUT WORDS IN MY MOUTH, IT'S DISHONEST.
Reckless drivers do not cause deaths then, nor deaths by dangerous driving cause deaths either, amazing! And playing with words, mmm them difficult words. Causing problems in arguments.
DON'T PUT WORDS IN MY MOUTH, IT'S DISHONEST.
Well this is clear codswallop, using words in the hope people don't think the words mean what they mean?
Everyone knows what reckless means, including you, that's why you keep putting the word in my mouth, even after I have expressly told you multiple times that that is NOT what I (or Adams) is saying. You persist in using the word knowing full well that anyone hearing you misquoting me, then witnessing a driver wearing a seatbelt will see that they aren't being reckless, and then wrongly conclude from that there must be no effect at all.
Here's Adams:
[ Invalid Attachment ]
So that's enough now.
If you can't demonstrate even the most basic level of honesty I don't propose to have any further communication with you, on either this thread or any other.
Post by: vhfpmr on 03/02/2024 16:14:51
which suggests that wnen car occupants wear seatbelts, more pedestrians wander into the road.Part of seatbelt legislation often requires children to be in the back seat, so some of those who would have died in the front seat now die in the back seat. And as far as I know, pedestrians are not defined as persons wearing seatbelts.
The reason more die is because motorists aren't driving as carefully, the same reason that more children died in back seats after they were made to wear seatbelts. Or are you going to suggest that children wearing seat belts are more likely to wander in front of the car?
So what is your explanation for seatbelts in cars increasing deaths among cyclists & pedestrians?
Something a bit less absurd than the suggestion that they are selectively jumping out in front of only cars with belted drivers would do.
Adams' work is genuinely lifechanging for those open minded enough to take on board what he says.
No sensible person disputes that people are more careful carrying a tray of raw eggs than a bale of wool, more careful to stay away from unfenced precipices than fenced, more careful crossing busy roads than quiet, more wary of dangerous animals than placid etc etc, and yet their senses leave them when confronted by the suggestion that they might be a bit more careful if they're driving with no seat belt or riding with no crash helmet. I climbed the rigging on SS Great Britain once. Would I have done it without a safety harness? Probably not, in which case my risk of falling from the mast would have been zero, a smaller risk than I incurred by climbing it.
Try asking a few people what they would do if you were to confiscate their seatbelts (assuming the law were revoked). In my experience quite a few will triumphantly tell you that they would quit driving altogether, seemingly unaware that they've just shot themselves in the foot with an example of the most extreme change of driving behaviour possible.
Post by: Petrochemicals on 03/02/2024 19:00:54
DON'T PUT WORDS IN MY MOUTH, IT'S DISHONEST.. I CANNOT PUT WORDS IN YOUR MOUTH. THE ARGUMENT HAS DEFEATED YOUR POINT. THAT IS THE ODD SENSATION YOU ARE AWARE OF IN THE CHASM IN YOUR HEAD. Stop attempting to stifle the conversation.
If scientific analysis is undertaken there is nothing in the prior arguments that would mean rear seatbelts would not save lives. Rear passenger seatbelts will not endow on a driver any sort of feeling of invunerability as far as i can see, especially as the driver will be already hypothetically emboldened with his own seatbelt.
There is very very clear corelation also on the previous graph of deaths.
[ Invalid Attachment ]
Rear seatbelts also do not neceserrily save the life of the wearer, as can be seen from above it would be very unlikely that rear belts would have no affect.
Post by: alancalverd on 04/02/2024 21:20:29
Adams' work is genuinely lifechanging for those open minded enough to take on board what he says.Is he a politician, a priest, or an economist? Your quote says absolutely nothing about what will or did happen, but merely mentions the possibility that something might. Openmindedness is not the same as uncritical reading.
Post by: alancalverd on 04/02/2024 21:22:28
No sensible person disputes that people are more careful ......crossing busy roads than quiet,which doesn't explain why most UK road deaths occur on rural roads, and fewest on motorways and A roads.