Safe Speed Forums

I am certain that tiny changes in average driver quality will reflect directly in the number of road crashes we experience nationally.

In other words:

Number of crashes is inversely proportional to average driver quality

This works in exactly the same way as 'number of bankruptcies is proportional to interest rates'. Those who are near the edge can be tipped over by the smallest change.

1) I note that this concept of 'working on a slope' is alien to many people. I'd like to understand that better.

2) I've coined the phrase micrometric influence to try to describe the concept that a tiny tiny change WILL have a real world effect. But is there a better term? Is there, perhaps, a known phrase that carries the same concept?

3) Does anyone REALLY doubt that micrometric influence is real and true?

4) Any other thoughts?

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

It sounds a bit like the butterfly effect in chaos theory. Tiny changes can have enormous consequences.

In the driving system it is quite obvious when you think about the number of interactions drivers have with other drivers each and every day. It only usually takes one small adverse event to start a chain reaction. Sometimes it will lead to a full blown accident, sometimes a near miss and sometimes it will be unnoticed. With congestion increasing too this is also tipping the balance towards crash and near miss away from inconsequential. It is ultimately a chaotic system with some rules on interaction. Even if everyone always followed those rules you can't prevent odd things happening which will still cause an accident.

Is the slope one which heads down to zero ie all perfect drivers equals fewest accidents or one which has a threshold ie average driver quality above this number and you have the lowest possible number of accidents considering the amount of congestion and mileage driven?

I suspect pedestrian injuries are also sloped in similar way ie an impact below a certain speed will never cause a fatalitiy. The current models probably assume the risk of fatality decreases down to a 0.1 mph impact. This obviously excludes those that are rolled over or squashed against something. The latter could have serious consequences for assuming how people will be injured and whether unncessarily dropping limits has not actually made an difference to the outcome but has made it more likely that pedestrians are hit due to inattention and speedo watching instead. But I digress...

That's not the way my mental models work - I see it all as quite 'linear' and not at all 'chaotic' (in the mathematical sense). I think the system is large enough that all the random elements are played out daily to give dependable statistical average results.

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

If you analyse the recent fatal crash at Plumton, then I am sure that you will find lots of small factors came together to create the nighmare scenario - and any one of them out of the equation could have saved lives.
Dr. L has the information on the physical aspects of the road - which was just part of a chain with a weak link.

I'm not sure that the public at large would understand the use of the term micrometric - but at this point, I cannot think of a better term.

A good illustration though would be to put a novice road driver on a formula one track, and even experienced F1 drivers might have an accident trying to avoid him (assuming they were ignorant of his lack of experience) which he might not be involved in himself, while he would be more likely to crash himself through not knowing how to handle the power.

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Time to take responsibility for our actions.. and don't be afraid of speaking out!

"Incremental"?

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CSCP Latin for beginners...
Ticketo ergo sum : I scam therefore I am!

Good word - but it comes with a picture of a finite step (at least it does for me) - whereas I was looking for a word that implied 'extreme smoothness' and sensitivity.

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

Ah.

To me the imagery it conveys is an infinitessimal but nevertheless definite movement, which is how I see this system working.

The changes we are trying to make are in themselves all but immeasurable, yet each ratchets the system by a tiny amount in the direction we wish it to go.

Aren't semantics fascinating?

Q. Where does the word "etymology" come from...?

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CSCP Latin for beginners...
Ticketo ergo sum : I scam therefore I am!

How about 'sensitive dependency'?

Or, depending on perspective: 'divergence'?


Would that be 'quantisation'?





......or when it comes to speed cameras: 'excremental'

I think the effect being described is probably best explained by using one of those 2p machines you usually find on seafronts. The ones that have flat surfaces filled with 2ps and a thing that moves back and forth pushing them towards the edge.

I'm not talking about the odds of winning, which are stacked against you as the coins are arranged such that it's hard to generate any movement, ignore that part and concentrate on the coins that are right on the edge.

Some will be hanging so precariously close, that a nudge of a fraction of a millimetre will send them tipping, wheras for the rest of the coins in the system you wont even be able to tell that they have moved.

I think this illustration would work better for an article describing declining standards in driving though. It may only be a small decline, but it's enough to cause real results.

Supercritical slope?

"One can prepare a sand pile with a supercritical slope, but
that state is unstable to small perturbations. Disturbing a supercritical pile will
cause a collapse of the entire system in one gigantic avalanche."

Not really what you are looking for I think, though the idea that a 'system' can be pushed into a catastrophic change with a tiny change may be relevant.

popular with management consultant types:

Kai-Zen

"gradual and orderly, continuous improvement"

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COAST Not just somewhere to keep a beach.

A young loner on a crusade to champion the cause of the innocent, the helpless, the powerless, in a world of criminals who operate above the law.

i'm a bit confused here..... the second statement clarifies the original reflect as referring to an inversely proportional relationship.

'working on a slope' implies (to me) a linear relationship whilst most of the responses have interpreted the relationship as non linear (i.e. quadratic or exponential curve).

so i cant really contribute anything further unti li understand what phenomenomenom we're trying to describe.

Since we have no units of driver quality we cannot determine the 'law' of the slope.

OTOH, if we establish the principle we could go on to specify driver quality in terms of crash risk thereby creating a linear relationship.

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

Ooo-er! It's totally off the original topic of the thread, but I LOVE it!

Safe Speed - the Kai-zen road safety campaign! Is there any element of Kai-zen that folk here DON'T recognise as already existing in Safe Speed's approach to road safety?

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

scrapping all speed cameras is NOT in the spirit of Kai-zen. The kai-zen approach would be to address each one in turn, individually, with only it's immediate environment (and not any political environment!) considered.

The outcome of a kai-zen approach to speed cameras (or preferably, speed limits) would be a spreading zone of appropriate speed limits and appropriate enforcements (some limits would go up, some would go down, similarly some cameras would go up, others would be removed). I sincerely believe the outcome of a kai-zen approach to speed limits would result in variable speed limits and increased motorway upper limits.

The beauty of a kai-zen approach is that it is always possible to do more. One way of representing kai-zen is to say that you will manage the "worst performing" based on comparison with the "best performing", and as each of the worst perfoming areas is addressed the new worst performing areas are identified.

In terms of road safety, it's easy to imagine what could be done. Find the stretch of road with the best safety record (this would require more information that just KSI's - the amount of information required is huge, incuding such variables as visibility, road surface degradation in the wet, even things like the grip on the road that allows accidents to be avoided as it supports ABS without sacrificing braking efficiency - if there is such a measurement or phenomenom, that is). Then compare these myriad of facts with the polar opposite, the least safe road (again, this is more than just KSI's) and identify an action plan for the lower end road.

It's more difficult to actually DO it.

In fact, I'd go so far as to say that kai-zen is the exact antithesis to a "Campaign". Can you imagine the mass rally in favour of adopting kai-zen road safety:

"What do we want?"
"Incremental continuous change"
"When do we want it?"
"Starting immediately and becoming a continual process that does not have a defined end point"

I'm a big fan of a kai-zen approach, I've described an approach elsewhere on these fora that is kai-zen like in it's approach (I'll search my posts for it and find a link). The thing is, the crucial thing, is that for kai-zen to work properly it needs to work on something measurable, and road safety is not easily measurable (yes, you can measure KSI's, but we all know there is much more to it than that). All of the variables need to be measured, and I don't think we (the taxpayers) have the stomach to meet that cost.

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COAST Not just somewhere to keep a beach.

A young loner on a crusade to champion the cause of the innocent, the helpless, the powerless, in a world of criminals who operate above the law.

I'd suggest that the Safe Speed approach to road safety would never have allowed cameras to flourish in the first place. The 'scrap all cameras' demand is simply to return us to the previous baseline of incremental improvement.

I also believe that in order to evaluate the effect of speed cameras we have to look at 'systematic' driver quality, and that since the influence of cameras on systematic driver quality is negative they really do need to go.

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

Agreed. I believe cameras would still have been introduced - but they would never "flourish". Any flourishing done in a kai-zen regime is glacial (slow but unstoppable). In a kai-zen regime, every single camera that was put up would be provably effective ... becuase if it wasn't, it would be taken down.

Wouldn't that be nice.

But you cannot "do" kai-zen by ripping up and starting from a different point, you have to start from here, from now.

You asked the question how safespeed is not kai-zen, that is the answer.

[fighting ... urge ... to .... say .... ahh sod it]

Grasshopper.

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COAST Not just somewhere to keep a beach.

A young loner on a crusade to champion the cause of the innocent, the helpless, the powerless, in a world of criminals who operate above the law.

Actually:

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

And the answer is still:

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COAST Not just somewhere to keep a beach.

A young loner on a crusade to champion the cause of the innocent, the helpless, the powerless, in a world of criminals who operate above the law.

I'm saying that the similarities between Safe Speed approach and kai-zen are an amazing case 'convergent evolution'. If you look at the Safe Speed model of 'how road safety must work and be improved' there seems to be a 100% correlation.

On the camera thing, perhaps we need to create an environment where it is safe and appropriate to start kai-zen? That's the way I see it anyway.

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety