Paris 0, London 16

I’m not a trained statistician, nor do I hold any transport policy qualifications.  However, I became interested in the numbers of cyclists killed in London after 1992, when Edward Newstead, a working cycle courier, was killed by a left-turning HGV on Oxford Street.  I did some campaigning on the issue of HGV killing cyclists, and to cut a long story short, I ended up in a working group with the Mayor’s Office, TfL, Roadpeace & London Cycling Campaign.

As part of that process, we looked at a lot of numbers. Some of the numbers that we looked at were even leaked and then misrepresented in the media. One thing I have learned, not just from that process, but through reading and listening to the likes of Tim Harford (More Or Less is essential listening for everyone, in my opinion), and other people that use statistics critically, is that when producing raw numbers, particularly road casualty numbers, it is really, really important to give some sort of context, and, the most crucial part, that if you do present seperately collected stats side-by-side, you must compare like with like, otherwise grossly inaccurate conclusions can, and will, be drawn.

For instance, if there is almost no use of powered two-wheelers (scooters and motor-bikes, also known as P2W), then you would expect the numbers of deaths and serious injuries (sometimes called Killed & Seriously Injured, or KSI) to be very low, perhaps even zero.  If this is reported as ‘no motor-cyclists were killed in Carville last year’ without also adding ‘but almost no motorcycles or scooters sold or ridden in Carville last year’, the potential exists for turning a non-story into a very big deal, with the officials of cities that have high rates of P2W KSI being asked by scooter clubs, ‘well, why is Scooterville so dangerous? Why can’t we be more like Carville, the safest place on earth for scooter riders?’  There then might follow questions from the media following up the enquiries of the scooter clubs, questions asked by members of Scooterville’s legislature etc etc, and the general impression given by the fuss is that Carville is somehow safer, whereas Scooterville’s streets are a charnel house of hot, twisted metal and broken limbs, into which no sane rider would venture, which is totally incorrect assumption, not supported by the evidence misrepresented by a not-like-for-like comparison between Carville and Scooterville.

So why am I concocting parables? I have seen various references to an astonishing reported fall in cycling fatalities in Paris.  The Times quoted city officials as saying: “the number of [cycling] deaths [in Ville de Paris] fell from six in 2009 to none last year (2011).”  The Mairie de Paris has some numbers on its web-site for cyclistes décès (that is, cyclists killed) between 2008 and 2010, as follows: 2, 5, 5, 6, 2 (no number given for 2011).  London’s numbers for the same period are: 19, 15, 13, 13, 10.  Looking at these numbers, it would be easy to come up with a headline such as London cyclists more than 8 times likely to be killed than in Paris!  (19, the number for London in 2008, divided by 2, the number reported for Paris).  I have also seen the numbers quoted as London 16, Paris 0 (there were 16 cyclists killed in London last year).

My initial reaction to seeing the numbers was that the reported numbers were wrong.  It seemed implausible that Paris, a city which is still trying to build up a culture of utility cycling (as opposed to cycle sport), should be so much safer than London.  Then I went to Paris over the summer, and I became even more convinced that the numbers were wrong.  Paris has some cycling infrastructure, but not all that much, and is certainly not light-years ahead of London.  Paris also really doesn’t have that many more cyclists than London, based on what I saw.  I would guess that London actually has more regular cyclists than Paris.  I would also say that Paris streets and traffic are about as hostile as London’s to cyclists, if anything, more hostile.  Which is not to say that Paris is all that dangerous for cyclists.

It’s difficult for me to be objective about danger to cyclists in cities, as I was a bicycle messenger for many years, and was (and still am) quite comfortable tackling Hyde Park Corner at speed, or any other street for that matter.  The only place that I ever felt threatened was the Upper Thames Street tunnel.  I used it because it was the quickest way to get from the City to the West End, but I wouldn’t now use it at all, as it’s unpleasant, and, in my opinion, just about the most dangerous road in central London.

Anyway, I didn’t find Paris all that scary (not even La Place de La Concorde, but, like I said above, I am quite happy riding around Hyde Park Corner), but compared to, say, Copenhagen, it’s clearly not as comfortable to cycle in.  By the way, while we’re talking about Copenhagen, let me say here that comparing Copenhagen with London just doesn’t fly.  Copenhagen is not comparable with London.  It is a much, much smaller city.  You can ride across it in less than an hour.  I’m not suggesting that there aren’t lessons to be learned from Copenhagen, but London should be compared with cities of the same size, i.e. metropolises, not small cities. (Copenhagen has a population of under 2 million; London has a population of 8 million, by the most conservative estimate.)

The very long and slightly shorter of it is that, in my opinion, London and Paris offer a fairly similar level of hazard to cyclists.

So, piqued by my own observations, I couldn’t let the number 0 go, after having actually ridden in Paris for a few days.  I emailed a couple of people, including Charlie Lloyd at the LCC, who has done a lot of work on KSI numbers, and knows his stuff.  According to Charlie, the Ville de Paris, from which these numbers are reported, is less than the size of TfL’s Zone 2.  The numbers reported for cycling deaths in Paris are taken from a much, much smaller area, and therefore not really comparing like with like.

So what is the like-for-like comparison?  In the last year, 2 cyclists have been killed in a similar-sized zone to Ville de Paris in central London, according to Charlie, who keeps track of such things. This means that a similar number of cyclists were killed in this area of London as in the Ville de Paris 2009 & 2010.

Also, no-one seems to have to hand the numbers for total km travelled by all cyclists in Ville de Paris.  The number wouldn’t be all that useful for a direct comparison with London, but you could at least get the km / fatality number for a rough comparison, which would be far more useful than simply quoting raw fatality numbers, which in any case, aren’t even directly comparable.

Paris 0 London 16?  Match referred to statisticians for further enquiries.

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5 comments
  1. It’s not easy to figure out the modal share, but this report seems to suggest that greater Paris has a modal share of around 2%. http://www.stif.info/IMG/pdf/Enquete_globale_transport_BD.pdf

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  2. 5 cyclists were killed in Ville de Paris in 2012. http://www.paris.fr/pratique/deplacements-voirie/dossier/prevention-et-securite-routiere/moins-de-deces-en-2012/rub_7096_dossier_55410_port_16333_sheet_23036

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  3. pm said:

    I think almost all the stats that purport to say something about safety based on raw KSI figures are flawed. Because they only tell you about the casualties that occur amongst the unrepresentative self-selected group who actually dare to cycle on roads. They say nothing about what the KSI rate _would be_ if everyone, careless and careful, risk-embracing and risk-averse, alike, were to cycle regularly.

    Unless you are talking about somewhere with Dutch levels of everyday cycling they don’t tell us anything about how safe cycling actually is (or would be) for ‘normal’ people.

    Also, official bodies like Eurostat are not above using rather odd statistics, e.g. here:

    http://epp.eurostat.ec.europa.eu/statistics_explained/index.php?title=File:Number_of_deaths_in_road_traffic_accidents_per_million_inhabitants_by_NUTS_2_regions_2008.PNG&filetimestamp=20101021093238

    What does “road deaths per capita” tell us? Surely what they should tell us are “road deaths per million miles travelled” or “… per motor vehicle”?

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