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Postby Psamathe » 17 Oct 2019, 10:14am

An interesting section in a Narked Scientists podcast about some research into SMIDSY causes (using simulators, eye tracking, etc.) and seems that often (in the case of motorbikes) the driver did see the motorbike but just immediately forgot about it (hence my SMIFY invention). A short term memory issue.

If anybody is interested in it: starts at 17:00.

(It's a fairly short item)


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Postby xjs » 17 Oct 2019, 12:56pm

Interesting, thanks for the link. Is there also maybe an element of the brain looking only for car-shaped things, so "car" = I can't go, "not car" = I can go?

I drive then cycle through the London rush hour every weekday morning and I know how easy it is to miss someone on two wheels, so I've stopped getting angry with drivers who fail to see me! I'll give the "bike" voice a go tomorrow...

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Postby mattheus » 17 Oct 2019, 1:27pm

xjs wrote:Interesting, thanks for the link. Is there also maybe an element of the brain looking only for car-shaped things, so "car" = I can't go, "not car" = I can go?


But in practice it doesn't matter which of the 2 effects is dominant - the brain user chooses to ignore certain road users before making a decision on what to do next. Unfortunately :( (rubs scar on forehead).

*If anyone hasn't seen it, google the "counting passes in a basketball match" video - it's VERY instructive!

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Postby drossall » 17 Oct 2019, 10:46pm

It's consistent with previous discussions, and with experiences of cyclists who have reported being certain that drivers had seen them, when those drivers then pulled out nonetheless.

It seems to me to be quite fundamental in our understanding of the road, and visibility. We forget, I think, when arguing that being more visible is a good thing, that it's a two-way process involving the other party perceiving you as well. So, it's impossible for everyone to become ever more visible and so keep increasing safety, since as road users we can only give a maximum of 100% of our attention to the road. It follows that, very quickly, we reach saturation, and greater attention paid to one road user can only be obtained by "stealing" it from someone else.

So I wonder whether we should not look to have legal limits on visibility, with the aim of sharing the available attention fairly. This links, for example, to the daylight running lights debate. It also helps to explain why any kind of unusual dress or appearance seems to make you more noticed (and therefore safer) on the road, even if the colours of the clothing are not the most visible ones by any usual measure. Tricyclists, for example, are plainly not more visible than bicyclists, and yet often report feeling safer.

It may also explain why erratic cyclists do not have as many accidents as one might expect, and why some experienced riders like to wobble strategically. Anything that breaks the SMIFY model is likely to help (but responsible choices need to be made).

None of this should be interpreted as advocating ninja cycling; it's not. However, there are stats around suggesting that unlit cyclists at night have far fewer accidents than one might expect, and indeed are under-represented in the accident stats by comparison with those using lights. The only explanation I can think of is that, on well-lit streets, unlit cyclists are sufficiently annoying to draw attention to themselves and hence avoid the SMIFY effect, and this has more effect than the lack of visibility.

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Postby Spinners » 18 Oct 2019, 7:34am

Some of the drivers who pull out in front of me when I'm on my bike definitely have that look on their chops that says, "I can see you but you're only a bike". :?
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Postby peetee » 18 Oct 2019, 9:03am

Spinners wrote:Some of the drivers who pull out in front of me when I'm on my bike definitely have that look on their chops that says, "I can see you but you're only a bike". :?

That sort of behaviour is inherent in so many road users when they encounter a vehicle with less mass or smaller dimensions.
Current status report:
Latter side of fifty and feeling less than nifty.
Too many bikes on pegs and too few miles in the legs.

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Postby Psamathe » 18 Oct 2019, 9:14am

I'd previously thought the pulling out in front of bicycles may have been the driver sees a bicycle and sub-consciously register as"slow" which becomes "not moving" so they pull-out whereas when they see a car they register 20-30 mph.

But the research in the podcast was with a motorbike and motorbikes would seem to suffer this badly and I can't see any way a driver would see a motorbike and register slow - so my previous thoughts are clearly not what is mostly happening.


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Postby mjr » 18 Oct 2019, 9:22am

This is a bit worrying because I thought part of the decision was "is this big enough to dent my precious?" and a motorcycle is, hence my preference for steady lights above the wheel and below handlebars... but this research suggests this isn't a winning tactic!
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Postby Pastychomper » 29 Oct 2019, 10:31am

In 2010 I read about a study that showed elderly drivers who played memory training games scored better on peripheral vision tests. Afair the article didn't describe the study design, so I wonder whether it simply mis-categorised SMIFY-like events as SMIDSYs, or something similar. Maybe small events at the edge of vision fall into a similar category to things not being looked for, and are immediately labelled as Somebody Else's Problem?

If memory-training games do make people more likely to notice what's around them then there's an opportunity for some simple and effective road-user training. I've been trying to remember to try such a game ever since...
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