Are you a nanokiller?

I have been intrigued for some time with Ronald A. Howard's idea of micromorts: a way of putting the risks we take in our lives on a human scale. The idea is that one micromort is a 1-in-a-million chance of dying. So, for example, if we say doing a skydive has a risk of 7 micromorts (as that Wikipedia page that I've linked to claims), that means 7 jumps out of each million lead to somebody dying. Or, in other words, if you jump from a plane there's a 7/1,000,000 chance you'll die (assuming you've used a parachute - without the parachute I suspect the chances are far worse). As we'll all die one day, of course, just being alive carries a background risk level of more than 30 micromorts, as the article also explains.

Anyway, I wondered if we might apply a similar principle to road deaths, as a way of making salient a very important point: each time you drive a motor vehicle, there's a small chance someone will die. I've long thought about how, each time I drive, I am effectively killing a tiny fraction of a person because I'm complicit in the overall number of deaths that take place. Today I realised that something analogous to the micromort concept provides a useful way of quantifying this.

So let's find some statistics! The Department for Transport statistics web page reveals that in the United Kingdom in 2012, motor traffic travelled 302.6 bn miles and led to 1754 deaths. Let's do the maths:

• 302.6 bn / 1754 = 172,519,954.39 miles for each death
• 1 billion / 172,519,954.39 = 5.8

And so, ladies and gentlemen, I present you with the nanokilling. Every mile you drive, you commit 5.8 nanokillings. Drive 12,000 miles in a year and you've committed 69,600 nanokillings, or 0.0000696 killings.

So clearly, the typical individual is fairly unlikely to kill over the course of their driving career. Let's say someone drives 10,000 miles per year for 50 years. 50 * 10000 * 5.8 = 2,900,000 nanokillings, or 0.0029 killings. This means you'd need to get together with about 344 other people before you could be reasonably sure that, collectively, you've managed to kill somebody.

But that's the thing, isn't it? 345 people isn't really that many. There's probably that many within a few streets of you. And there are a lot of streets in the country, aren't there?

Obviously the nanokilling would need to be recalibrated from time to time as new statistics on numbers of deaths and the amount of travelling that took place to cause them emerge, but of course that's also kind of beside the point. The point is that as long as there is motorized travel and deaths on our roads, the number of nanokillings will never be zero, which means the fundamental point of this article will endure - when we use a motor vehicle, we commit nanokillings. Unless you foreswear motoring (and the products of motoring, and do nothing to push for alternatives) you're to some extent complicit in causing little bits of a death. I know I am, even if I'm not happy about it.

Thinking out loud: Are cyclists the new weather?

You find yourself standing next to a stranger, perhaps in a pub or a Post Office queue whilst waiting an unbelievable time for a simple stamp. You decide to strike up a conversation with this person to pass the time. But what do you talk about? The list of topics one can raise with a stranger is quite slim. You can hardly start out with "Isn't the current Prime Minister an incompetent buffoon?" as you risk upsetting their political sensitivities. Sport is also risky - they might support a team you do not. So what's safe? What can you be sure they'll not get offended by? Two topics that never fail are weather and traffic.

"Traffic's bad today, isn't it?" is as safe a conversation opener as you can find. The traffic might be light, but don't worry: this won't go challenged. What else is a safe opening line with a stranger? How about "It's hard to find a parking space, isn't it?" or "Cyclists are a nuisance aren't they? Always riding through red lights and on pavements?" Nod nod nod. Safe. Nobody's going to be offended here. We all agree, just as we all agree that winters aren't what they used to be.

These statements about cyclists, of course, raise the hackles of cyclists a great deal. One only needs to look at yesterday's drama about a survey of red-light jumping behaviour and how it was reported. The old saw about cyclists and red lights is one of a family of statements that are so often repeated I recently suggested somebody should make a bullshit bingo card: red lights, pavements, no tax, no insurance, license plates, helmets, lycra...

And this got me thinking. Yes, these statements are repeated an AWFUL lot, aren't they? I've been hearing them regularly for at least 8 years. They crop up in the comments on almost every article about cycling that gets published online (they'll appear below this, no doubt). Yes, they recur suspiciously often. Hmm...

The thing is, what should we take from these statements? Should we take them as evidence for endemic anti-cyclist feeling? I'm starting to doubt that. It's the fact these statements are repeated SO OFTEN and practically verbatim from a hundred thousand different mouths and keyboards that got me thinking. Because they appear almost as a reflex, and because so many people who don't know one another repeat exactly the same phrases, I suspect that these aren't true opinions; I reckon they are merely memes. They are cultural conventions that have grown up over the past years.

I'd like therefore tentatively to suggest that all these statements such as "Cyclists? They all ride through red lights, don't they?" are fundamentally NOT ABOUT CYCLISTS and should not really be taken as such. I believe they are really a set of social conventions that serve the same role as conversations about the weather: They allow a socially acceptable and safe way to find common ground with strangers. They are (in many people's minds) as uncontroversial as statements about how gravity still seems to be working fine, or how politicians can't really be trusted. They are not intended to challenge or provoke; they are intended to provide comfort through the repetition of a familiar and long-standing ritual, not unlike a religious service.

So perhaps we should not make the mistake of thinking that such statements are the product of considered thought, or really represent people's true opinions. People have not looked into these matters deeply enough to really have deep-seated opinions. If people really studied the weather and climate data they'd stop saying that winters aren't what they used to be. If they studied the traffic behaviour and accident data, they'd stop pointing fingers at cyclists.

Because these beliefs aren't really being examined in depth, people take evidence as it comes rather than going and looking for it, and when this happens one usually sees confirmation bias: the tendency to pay attention to information that confirms what we already believe and ignore information that challenges it. So a person doesn't really notice 25 cyclists stopping at a red light and 50 riding on the road, but spots the one who cuts the light and the one who rides on the pavement because these are what they expect to see.

Of course, the notion that a subgroup of society is a menace could not have taken hold were that subgroup not relatively small and perceived as outsiders. The context in which these social norms arose is fascinating and something I've also thought about, but would be a digression here. The main point I want to explore is that perhaps these statements we see so often are merely conventions that are repeated as part of the social glue that holds society together, and do not necessarily reflect people's true opinions about cyclists.

At first glance, the idea that these incorrect views about cyclists are not deeply examined convictions might suggest they will be easy to change. But if I'm correct in what I'm thinking here, we'd have to suggest the opposite: these views will be difficult to change - they came to hold the position they do in our society because they seemed so self-evident and obvious. Perhaps to challenge the idea that cyclists are all law-breakers is like challenging the idea that winters aren't what they used to be.

Why I hate pedestrians

You know what I hate? Pedestrians. That self-satisfied, striding, boot-bedecked bunch of scum. Is it just me, or does the country suddenly seem to be full of them? I've never tried walking anywhere myself -- why would I? I'm a successful adult -- but it seems I can hardly travel down the street these days without one of them stepping off the pavement in front of me without looking, their face set in a holier-than-thou expression as they jump out of the way of my car in a burst of expletives. Something clearly needs to be done, and it's good that the government are starting to realise this.

The thing is, it's not just that pedestrians are all smug and annoying when they bang on about "health" and "pollution". That's sickening enough, but if their smugness was the only problem I could just ignore them - after all, they and their silly 'shoes' flash past quick enough when I get going, and their smugness can't penetrate my car's tinted windows. But the thing is there's more to it than that, because have you noticed that even though pedestrians walk millions of miles on our road system every single day, they contribute nothing at all to the cost of that road system? They have thousands and thousands of miles of dedicated pedestrian-only travel routes -- pavements, they're called, or sidewalks if you're that way inclined -- which they don't pay a penny for! Whilst honest motorists are taxed left, right and centre, they don't pay anything at all for all these facilities they enjoy. It beggars belief.

And recently, of course, it's got worse. As I'm driving up the street I constantly come across pedestrians walking across my part of the road to get from one of these pavements to another. I mean, what the hell...? Do they want the shirt off my back as well? They've been given vast tracts of pedestrian-only routes, where I'm certainly not allowed to drive, but apparently this isn't enough for them. Oh no, they want to keep encroaching into my space as well. Sure, we've all heard these walking zealots who say that it's because the 'pavements' don't form a joined-up network, meaning they can't walk to where they want to go without having to step onto the road from time to time. Aw, bless their little hearts. To pedestrians I say this: get off my part of the road. If you walk there when I'm coming along then I'll happily run you down, that's all.

In the long term there's clearly only one solution to all this. If pedestrians want to walk on our streets, which we pay for with all our driving taxes, then they need to pay their share and take their part of the responsibility. Anybody who walks anywhere should undergo training, should have to pay an annual tax towards the facilities they enjoy, should display a license plate so they can be identified, and should each be made to carry insurance in case they are ever involved in any accidents. Until then, they can sod off back to Shoeville or wherever it is they go when they aren't freeloading off the rest of us.

Research with People published

It's a red-letter day in the Walker household. My textbook, Research with People: Theory, Plans and Practicals has been published. This is a practically based introduction to the issues involved in human testing. It is written to work for anyone who needs to collect information from people - medics, psychologists, sociologists, management types, etc. - and also works for readers who don't carry out research but who want to understand the research process so they can better make sense of what they read. Enjoy!

A (red) herring in the shower

A few days ago I was asked by Tom Vanderbilt, author of the very readable and interesting book Traffic, to write a piece for his blog summarizing my thoughts on bicycle helmets (thanks, Tom).

Karl McCracken has written some interesting words on the subject as well today. The thing I'd like to pick out of his post is the issue of showers. Like Karl, I have again and again heard people say "Oh, I'd love to cycle to work but we don't have any showers so I can't." Let's have a little look at this, shall we?

When I was doing work on how drivers overtake bicycles, I needed somewhere in Bristol to store my bicycle between testing sessions. I called Sustrans and asked them if they had somewhere I could keep my bike. "Yes, we'll find somewhere," they said. "Just turn up."

When I arrived, where do you think was the one place in the building - a building where everybody cycles to work - that was unused? The shower. And sure enough, that's where the bike was stowed.

Item 2. Last year I attended a meeting at the CTC's headquarters in Guildford. Again, this was a building where everybody cycles to work each day. I saw their shower, and I don't think it had ever been used once.

I think we can learn something from this. Here are two buildings in which the whole staff cycle in every day, and in neither is the shower used. It is clear that showers are a red herring. Like bad weather, they seem a huge concern to people who do not cycle but, after only a little experience, everybody realises it is just not the issue they thought.

So heed my words, people! Of course you'll be a little sweaty the first couple of times you cycle to work because you're not fit! Give it a fortnight and it will no longer be an issue. My workplace is on top of a mountain and I've never showered after getting there. If I have been a little sweaty, simply rubbing it off whilst it's still wet is all that's needed to avoid any smell. And cyclists: spread the word. We need to fight this barrier by showing people that it's just a non-issue if they will only try.

Or could it be that people know showers aren't really an issue, and use a lack of showers in their workplace as a way of justifying a no-longer-acceptable preference for driving? Oooh, what a cynical thought.

What's changed, behaviour - or the willingness to talk about it?

The University of Bath, who graciously stick a few quid into my bank account each month, have just completed a large survey of how people get to the campus. The headline finding is that between 2002 and 2008 the proportion of staff driving to the university has dropped from 69% to 58% and the proportion of students driving has dropped from 29% to 12%. Proportions of people catching buses, walking and cycling have gone up.

So does this represent a dramatic shift in behaviour? I hope it does, and that's certainly how the university will perceive it. But this is a campus whose many and massive car parks are groaning, despite being greatly expanded in area since 2002, and where the buses do not appear any more full or numerous than they did 6 years ago. This all leads me to suggest an alternative interpretation for these findings: people who drive are no longer as willing to discuss it as they were in 2002.

If you regularly do something 'wrong', would you take the time to complete an optional survey on that behaviour? How about if you do something perceived as virtuous? It just seems quite likely that these days, a cyclist or pedestrian is more likely to fill in the survey - and thus receive a little glow of satisfaction from talking about their sustainable travel habits - than a driver who will more likely receive a little twinge of annoyance at yet another attack on their habits. So the survey captures a greater proportion of the cyclists and pedestrians than the motorists, which creates an illusory shift in travel behaviour.

Unfortunately, I can't see a solution to this which doesn't involve obliging people to take part in surveys. But as short-distance car-use becomes less and less socially acceptable, we'll have to expect to see more bias of this sort creeping into transport surveys. And we need to be very careful we don't interpret this as people driving less and cycling more!. Mark my words, this mistake will happen.

Of course, if I'm correct in my interpretation, we might try to read these figures as showing that driving to the university is 100 * (1-(58/69)) = 16% less socially acceptable amongst the staff than it was 6 years ago, which is at least a small victory!

I am a scientist...

I've spent the past two weeks taking part in an event called I'm a Scientist, Get Me Out of Here. This was funded by the Wellcome Trust and was all about forging links between professional scientists and school students to further the students' understanding of science and remove a lot of the mystique that surrounds the area.

I was in a knockout contest against four other scientists - two cancer researchers, a chemist and a cosmetics researcher. Over the fortnight students from around the country bombarded us with questions about our work (and ourselves!), and we took part in many frantic live chat sessions where we were grilled mercilessly and made to defend our work in short snippets of text. They voted somebody out every few days.

And the result of all this is that after a week of eliminations, yours truly has been chosen by the students as the winning scientist. I win £500 for science communication - woo-hoo! I'm very surprised: I really thought one of the cancer researchers would get it (not only did the students clearly see cancer research as really worthy, but they were both much nicer than me in the chat sessions!).

But tempting as it is to gloat about winning, I see this as a victory for psychology rather than me. From the questions I was asked (which you can read if you look at the website - log in as a guest and choose GCSE 2 from the menu at the top), it was clear this was an area that the school-aged students simply hadn't been exposed to, and which they found really interesting. School science teaching is rooted in the 'big three' of physics, biology and chemistry, and these are massively important subjects. But there is clearly an appetite for psychology amongst the students too. Already hugely popular as an A-level, it's time for a lot more schools to start offering psychology at GCSE too. If nothing else, it surely would act as a powerful way of keeping girls interested in the more scientific end of education.

Segways and the law

Here's a cutting I ripped from the painfully inoffensive Metro newspaper a few weeks ago. It's about the House of Lords - Britain's strange, unelected upper chamber - discussing whether Segways should be legal. I love this story, because there are clearly so many layers of untold story behind the scenes...

Lords: Give green light to Segways
Scooters known as Segways should be allowed on the roads, peers said yesterday. The electric two-wheelers got the backing after peers tried them out.... Segways are used by police and the public in parts of Europe along with the US. There have been concerns here about safety. But [Liberal Democrat] Lord Redesdale said: 'I drove one straight at Earl Atlee and failed to do him any damage at all.'

Doesn't that last sentence just reek of disappointment?

[Edit: I just found the whole debate here. There are a couple of words missing from Metro's report... "I drove straight at the noble Earl, Lord Attlee, with his consent, and failed to do him any damage at all - unfortunately!" I was right about the disappointment!]

The family minibus

I have a neighbour who regularly travels with his wife and their two children. To move the four of them around, he bought a minibus with 20 seats.

'Why have you done that?' I asked, choosing my words carefully. 'There are only four of you - wouldn't a car make a lot more sense? It would take up less space and use a lot less fuel.'

He gave me a level look. 'But once every six weeks it's my turn to take my son's football team to their match. I need a vehicle with 20 seats.'

'Er, okay. But why not buy a normal car and just hire a minibus on the odd occasions you need one?' I asked. 'It would be a lot cheaper, and probably easier for you.'

'Oh, who can be bothered with that?' he replied, and stomped off.

Okay, so this neighbour is fictitious, but I've had almost exactly the same conversation with many people, with the only difference being that the numbers are all 5 times lower. There are so many people who buy a car with five seats primarily to move one person around. When challenged, they always point out some achingly unusual event as justification ('What about when I need to take rubbish to the tip?') I mean, what's that? Twice a year? Three times?

As plans for congestion charging force us to think about the consequences of our travel more and more, it is the sheer bone-crunching illogic and irrationality of this thinking that drives me crazy. Cars are fundamentally badly designed in various ways (e.g., their need for huge slurpy soft tyres to stop them flying off the road), and one of their basic design faults is that they take up the same amount of valuable road-space to convey one person as five. As I've mentioned before, people are going to have to realise that if they travel alone 95% of the time, it is better for everyone - including them - if they get a one-person vehicle and hire something bigger on the odd occasion they need more space. It's such a shame that we're going to have to go through masses of congestion and heavy-handed legislation to make people act rationally. Bah.

Yellow lines

, originally uploaded by Alex Craven.

There has to be a better way to manage parking than these eyesores.

Road Injury Severity Map of England

Here's something curious. Using the Department for Transport's road accident statistics for 2006, I calculated road accident severity figures for each county in England. The DfT's accident figures include a Killed-and-Seriously-Injured (KSI) statistic, which is the count of the most serious road injuries: those leading to... well, death or serious injury. For each county, I divided the number of road accidents with a KSI outcome by the total number of recorded accidents. The reasoning was that the higher this ratio is, the more severe the outcomes of that county's road collisions tend to be and, in one sense, the more dangerous that county's roads are.

The statistics I computed gave figures ranging from just 5.6% of road accidents having KSI outcomes (in Plymouth, where it seems most road accidents tend to end okay) to 23.7% (in North Yorkshire, where almost one-quarter of all road accidents lead to someone being killed or seriously injured). I then normalized these values to lie on a scale from 1 to 100, converted these into saturation levels of the colour red and filled in the counties on a map. Yes, it took a few hours.

The map reveals a few points of interest:

* We have to work in call centres, but at least we don't get squashed too badly - Former heavy industrial areas around Manchester, Merseyside, the West Midlands and the Potteries stand out as having quite low accident severities.

* Leafy suburbs, dead bodies - the affluent south-western corner of Greater London suffers quite a lot of serious road accidents. It's so tempting to make a link to all the SUVs...

* Mad Crazy Viking Berserkers - North Yorkshire and the East Riding. One in four road accidents in North Yorkshire has a serious outcome. My father lives there. I'd like him to move away now.

* Wiltshire and Northamptonshire are really dangerous - I live in Wiltshire! Can everybody take more care please?

* Odd pockets of safety - Plymouth wins here, but there are other counties that stand out from their neighbours: Surrey, Rotherham, Newham in London.

Sadly, these statistics aren't broken down by county for Wales and Scotland. However, overall Wales is at a similar level to Southampton and Coventry, with just under 11% of road accidents having a KSI outcome. Scotland is somewhat worse, and with 17% of all road accidents ending in death or serious injury is similar to Essex and East Sussex.

My hope in doing this was that novel insights might reveal themselves if I looked at the accident data in a new way. I wondered if there would be a North/South split, or patterns that follow motorways. Perhaps the most striking thing to emerge here is the suggestion of more serious road accidents in rural areas. (Most notably, wherever there is a city that has separate figures from the county that surrounds it -- Reading in Berkshire, Leicester in Leicestershire, Poole in Dorset -- the city always has a lower accident severity score than the surrounding county.) This seems on the face of it to support the idea that higher levels of road crowding and reduced speeds are good for reducing the severity of road accidents, although we must also consider other factors specific to rural areas such as twistier roads which give poorer visibility, and possibly higher levels of drink-driving. But then we have to explain why Devon and Cornwall -- perhaps the most rural and twisty-roaded counties -- aren't particularly bad.

Like all good data explorations, this raises more questions than it answers, but I think it shows the value of looking at data in novel ways.

Drinking and driving

During a commercial break on television last night I saw two adverts in quick succession. One was for vodka. Vodka is great stuff, but the advertising can't tell me this. It has carefully to ensure that no images or messages are used which might make me see it as enjoyable, because this could make me, as a blubber-minded member of the public, use it irresponsibly. And in case there's any lingering doubt about how much I'm not supposed to enjoy the vodka, the advert is plastered with the slogan "Drink responsibly" and points me to a website where I can learn how to drink less.

This advert was followed by one from Renault, selling a car which plops out noxious pollutants, is built to exceed the legal speed limit and is quite capable of killing innocent people. It was marketed with lots of exciting images of the car being driven wildly and ended with the slogan "Serious Fun". You can watch it, if you like.

Isn't there an inconsistency here? Alcohol: most people people enjoy it but it can cause harm if abused = constant warnings and can't be marketed as making your life more fun. Cars: although some people enjoy them, they cause harm when used normally = no warnings, and the marketing can promise sex and fun in return for using the product.

Surely the time has come for car companies to go where the drink companies have gone? Renault could have an advert which focuses solely on some minor aspect of the product's design -- the shape of the gearstick, for example, with resolutely no mention of how people might feel when driving the car. It would then display warnings like "Please enjoy the Twingo responsibly". Naturally oil companies should carry similar exhortations in their commercials too. And of course, both types of advertiser should direct consumers to websites where they can be helped to spend less money on the the products of the people paying for the adverts. Just a thought.