Safest day to cycle?

February 19, 2015 Leave a comment

Here’s a count of all cycling fatalities in California from 2001 to 2012, tabulated by year and day of week. The raw data comes from SWITRS.

Monday Tuesday Wednesday Thursday Friday Saturday Sunday
2001 10 17 18 21 20 21 14
2002 16 16 15 19 26 15 13
2003 19 19 15 20 19 18 15
2004 17 11 13 20 12 17 34
2005 16 21 16 18 18 20 23
2006 17 20 22 23 28 22 23
2007 14 21 23 17 15 21 14
2008 16 19 23 16 20 11 26
2009 18 13 18 7 22 15 16
2010 22 8 10 19 18 14 20
2011 21 14 23 15 22 29 18
2012 21 16 23 26 28 22 16
Totals 207 195 219 221 248 225 232

Is there any knowledge to be gleaned here about the safest day to cycle? One of the biggest problems in analyzing SWITRS cycling data comes from the lack of base rates, or overall counts of cyclists for a given period. The single worst day came from the 34 people who died on Sundays in 2004, but without knowing whether many people were cycling on Sundays in 2004, we can’t determine the rate of fatalities, and there’s not much we can derive about safety from these numbers. In a word, then, we don’t know when it’s safest to ride.

Still, my guess is that cycling rates climb on the weekends. If that’s true, we should expect to see higher fatalities overall on Saturdays and Sundays. They don’t show here in the totals for the weekends, which look rather like the rest of the week. The cause could be as simple as less car traffic on the weekends, or as rich and complex as this notion of safety in numbers, the idea that so many people are cycling on the weekends that drivers notice them.

Ultimately, we really need better information about cycling in California. We don’t know much about ourselves, how many of us ride, when we do, how we get into crashes, and why.

Categories: Safety Tags:

Helmets: Are bad stats leading to bad bills?

February 12, 2015 2 comments

California state senator Carol Liu introduced an all-ages bicycle helmet bill yesterday, much to the dismay of many people who know a thing or two about helmet legislation. The early betting has the bill dying quickly in committee or elsewhere, although in a sense it might be productive to have a full and lively hearing about the merits of bicycle helmets. Some of the dismal, even disastrous, examples from places like Australia and New Zealand — where helmet legislation has apparently had no safety effect while also reducing cycling significantly — might kill these ideas for years to come.

Senator Liu’s press release included this statistical “gem” taken from a report by the National Conference of State Legislatures (NCSL): “Ninety-one percent of bicyclists killed in 2009 reportedly were not wearing helmets.” Since she mentioned it, Senator Liu is apparently relying in some part on this number to make her case. Where does it come from? Does it hold up to scrutiny? Does it reflect the California experience?

The underlying NCSL report doesn’t mention sources, but it’s a pretty safe bet that its numbers are coming from FARS, the federal Fatality Analysis Reporting System. FARS, in turn, gets its data directly from state highway data collection systems, which are implemented at the local law enforcement level. In California, the Statewide Integrated Traffic Records System (SWITRS) plays that role, and its data is open to all comers — including me, as it happens.

Over the past few weeks, I’ve been toying with SWITRS data, trying to understand its structure, and looking into what it might reveal about our roads. I’ve only gotten my feet wet with it so far, and I’ve much to learn, but from what I’ve seen, Liu’s “ninety-one percent” number is problematic. Take the year 2009, the year she singles out for mention. FARS shows 628 total cyclists killed in the U.S. that year. SWITRS tells me that 107 California cyclists were killed in the same year; presumably, those 107 are included in the 628 total. How many of those killed California cyclists were wearing helmets? SWITRS tells me there were twenty-two cyclists wearing helmets, sixty-seven who weren’t, and eighteen unknowns. In other words, in California sixty-three percent didn’t wear helmets — not ninety-one percent, as the nationwide number suggests — twenty-one percent wore them, and for seventeen percent of cycling fatalities we have no data.

My point might be small, but it should be in the mix nonetheless: Senator Liu implies that only eight percent of killed cyclists are wearing helmets, but in California that’s just not the case. More than double the cyclists are wearing them, and even more might be, if we knew more about those many unknowns. The hard facts? Lots of Californian cyclists are being killed despite their helmets, just as other studies show. We need to spend time confronting the real factors, like bad road design, high speed limits, and poor cycling infrastructure if we expect to make a real dent in fatalities.

Where does FARS get that huge ninety-one percent number? I’m not sure yet, but it sure looks suspiciously like they are grouping the unknowns in with the nos. That is a big no-no!

Just for completeness, I went back and extracted the numbers for all the years for which we have full SWITRS data (2001-2012):

Year No Helmet Helmet Unknown No helmet Helmet Unknown
2001 76 17 23 116 66% 15% 20%
2002 78 22 15 115 68% 19% 13%
2003 81 27 18 126 64% 21% 14%
2004 74 27 22 123 60% 22% 18%
2005 75 20 37 132 57% 15% 28%
2006 100 34 21 155 65% 22% 14%
2007 76 25 23 124 61% 20% 19%
2008 73 30 27 130 56% 23% 21%
2009 67 22 18 107 63% 21% 17%
2010 67 24 20 111 60% 22% 18%
2011 81 33 26 140 58% 24% 19%
2012 77 49 20 146 53% 34% 14%

As far as I can see, never in the past twelve years of data has any year approached Senator Liu’s number. Whatever comes of Senator Liu’s legistration, we should make sure that incomplete data don’t lead to bad statistics used to justify bad policy enshrined in unhelpful laws.

Categories: Helmets, Law

Do Dutch women have more time to cycle?

October 12, 2014 Leave a comment

In a puzzling October 3 opinion article published in The Guardian, Herbie Huff and Kelcie Ralph argue that Dutch women cycle more because they have more time than U.S. women. The authors say this extra time comes from different Dutch cultural norms and social policies — like generous paternity leave — along with better city planning that makes distances between errands shorter. They conclude that improved cycling and pedestrian mobility in U.S. cities will require deep changes to social policies, ideas with “far-reaching implications and [that] require serious value shifts.”

These are thin arguments with shaky foundations. The paper they cite looks at time use in American households only. They present no equivalent study showing how Dutch households allocate time, and no studies on whether different social policies actually give women more time to cycle. Without such studies, one could invent results out of thin air. Without research to tell us, for example, how Dutch fathers spend their paternity leave, why can we assume they actually use it to help out at home? Maybe, instead, they spend more time on non-family leisure pursuits — like playing more golf. Maybe paternity leave actually changes mothers’ lives hardly at all.

But even if we grant them their assumptions, Huff and Ralph haven’t shown why giving women more disposable time means more cycling. The implicit assumption is head-scratching, that somehow women use extra time riding bicycles instead of doing something else. How can we assume this about any person or culture? Would the opposite hold — would Dutch women ride less if they had less disposable time? Would time-rich U.S. women suddenly opt to cycle? How do we know that cycling is the go-to activity once women gain more time?

Huff and Ralph don’t tackle counterexamples like New York City, where more than half of households don’t own cars and yet somehow find the time to chauffeur their children around town, all without Dutch social policies. They also don’t address why U.S. women in child-free couples, and single women without children — both classes of women presumably with more free time than their child-rearing compatriots — are less likely to cycle than their Dutch counterparts. They discount surveys where women say straight out that they are afraid on the road, effectively belittling women and their opinions. They also don’t tackle the problem of countries with social policies similar to The Netherlands (Norway, Finland) that have low-ish cycling rates.

One of the subtle and insidious assumptions underlying this article is that cycling is primarily a hobby or non-essential activity. In the cited study, cycling comes in for a mild whipping with the unsubstantiated claim that errands are “easiest to do in a private vehicle, and hard to do on a bicycle or public transit.” That is, only those people with extra time on their hands undertake cycling, perhaps because it’s slow. This assumption came under some small scrutiny in a quick Twitter exchange I had with @JennyGoBike, a car-free mother-of-three in Seattle: “Don’t assume cycling harder til you’ve wrangled 3 tots into minivan. Challenges to both.”

The Dutch — in my experience more practical and as time-conscious as any American — have created the infrastructure that turns that assumption on its head. The Dutch don’t cycle because they have extra time; they cycle because they have no time to spare. They cycle because cycling is the fastest way to get around.

The way I see it, Huff and Ralph have worked a little too hard to find a link between Dutch social policies and cycling. It may be the case that such policies are superior to American ones in every possible way, but the essential lesson of Dutch cycling does not come from them. It comes, instead, from the city planning and infrastructure build-out that has elevated cycling to a first-class, time-saving, and normal way to get around.

Categories: Dutch cycling, Planning, Policy

Now that we’ve the three-foot law, what’s next?

September 16, 2014 Leave a comment

After years of contention and a rocky path towards passage, California’s three-foot rule finally takes effect today.The law requires drivers to pass cyclists by three feet or more, and penalizes them with a small fine if they fail to comply.

How far is three feet? This will be among the many difficulties of enforcing the new law, and will likely limit its impact. Obviously, if a cyclist actually gets hit, that qualifies as a violation (but then the law won’t have made that cyclist safer); otherwise, it’s a judgment call that any good attorney will turn against the state in court.

How far is three feet? If this new law is to have any teeth, we need to define exactly where the boundary lies. While I’m not a big fan of painted infrastructure, one way to show what three feet means is through “bicycle-priority lanes.” Unlike existing bicycle lanes, which exclude motorized vehicles, bicycle-priority lanes would give first precedence to cyclists and second precedence to all other motorized users. As Peter Furth points out in his paper on the subject, the “magic of lines” comes from the “objective boundary of the bicycle zone” they provide. Drivers would know exactly how far they need to go around cyclists, and cyclists would have a defined place on the road.

Priority lanes are stepping stones towards proper separated bicycle lanes. They may help solve that perpetual chicken-and-egg problem of infrastructure, perhaps inducing a few more cyclists onto the streets, and giving us a few more voices for better facilities.

Categories: Lanes, Los Angeles

Begging for scraps at motordom’s table

September 8, 2014 Leave a comment

David Arditti of Vole O’Speed writes about 1934, the year “it all went wrong for cycling in the U.K.,” quoting Chris Peck of the Cyclists’ Touring Club: “‘We were still very much of the mind that we should try and recapture the roads from the motorists, so the construction of cycle tracks was seen as defeat.'” Perhaps if they had looked a bit west, across the pond, they might have seen the automobile experience in the U.S., where “[b]y 1930 most street users agreed that most streets were chiefly motor thoroughfares” (Fighting Traffic, Kindle loc 93 of 4958). In an ironic twist, the English viewpoint came full turn to a sleepy 1970s Palo Alto, where U.K.-born John Forrester successfully scuttled the city’s proposed separated bikeways as “at least 1,000 times” riskier than the streets, citing the CTC’s experiences. Perhaps if the city council had looked a bit east, across the pond, it might have seen that the British example didn’t work, and that by 1970 cycling usage had declined to about three percent from double-digit post-War highs.

If you’re of a mind to want bicycle paths and cycle tracks, you’ll likely lay much blame for their non-existence at the feet of these cycling pioneers. Their voices, the most powerful of their times, carried the day. It’s also a sobering thought to realize that they were our own, advocates for cycling, who believed the best path forward lay in achieving parity with other road users. They were fighting marginalization and segregation, terms that in most other contexts everyone fights, and they did too. Perhaps they saw the future all too clearly, the increasing and triumphal advance of “progress,” the historically inexorable march towards motorization, and the inevitable domination of the automobile. In this context, it was a positive result that cyclists still had access to the roads. The alternative might have been outright banning.

These men and their organizations “won” our access to the streets. But it was a proverbial pyrrhic victory. Yes, the vehicle code still allows us — and horses (?!) — on the streets, but one can’t help but agree with Arditti that a one-percent modal share proves a banning “more effective than could ever have been achieved by legislation.” In our fight for access, we have missed the bigger picture, that cycling is now damned dangerous and all but impossible except for the brave. In our fight against marginalization in terms of access, we have been marginalized in terms of use.

Last December, Milt Olin was killed by a sheriff driving his patrol car distractedly. Two weeks ago, the Los Angeles District Attorney released a detailed analysis of the incident and declined to press charges. Outraged, Los Angeles cyclists have asked the DA to reconsider by organizing a ride in Olin’s honor and holding a candlelight vigil. [The story continues to develop.] All of these actions are well-intentioned. But I wonder whether we are asking for the right stuff. Is a call for “justice” for the harm and injury that drivers inflict on us really going to make our streets safer? By calling for enforcement of laws, rather than installation of infrastructure, are we asking for the same meager and awful road access our forebears misguidedly demanded? Are we still begging for scraps at the table of motordom?

I think we should really focus whatever political capital we have in the direction that it will do the most good. We can argue the viability of the Olin case to no end. The DA reached one conclusion, you may reach another. It’s a judgment call. Meanwhile, the Olin family will have its day in civil court, perhaps winning millions from a defendant with deep pockets and accountability. That is justice too, and it’s more justice than most injured cyclists and pedestrians are ever able to achieve, in this day of rampant hit-and-run crashes and uninsured motorists.

Unfortunately, the Olin case is not unique. All road users are fallibly human, and this predictable, tragic story will be told again someday with a new cast of characters. We need to ask for stuff that “stops the murder,” to paraphrase the 1970s Dutch protests. Instead of justice, a form of which Olin’s family may get anyway in civil court, why can’t we instead ask for infrastructure? A long stretch of K-rail installed alongside the Mulholland Highway bicycle lane will do a better job of protecting future Milt Olins than all the “justice” we can get. Why not ask for cycle tracks? Why not ask for a meal instead of scraps?

Categories: Policy Tags:

Stuff happens

July 24, 2013 1 comment

A banal right hook, barely avoided, haunts me today, the scenario running through my head, questions of what happened and what lessons I can take from it. In less time than it’ll take you to read this paragraph, the incident came and went. The driver of the gray Prius, headed west on Santa Monica in West Hollywood, decided to make a right turn across my path in the bike lane and into a driveway. I didn’t see a blinker, or I might have been able to brake earlier. As it was, I don’t think I had more than a car’s length of space to react. Somehow, nearly a miracle, I maneuvered right, the driver came to a stop, and only my left shoe kissed the front bumper of the car. Crash avoided, but only just.

As I shook off the willies and continued on towards home, I wondered what the driver of that gray Prius was thinking. Given all the anti-cycling rants I’ve heard and read, there’s as much reason to believe that the driver blamed me for being in the bicycle lane, for “appearing out of nowhere,” as there is to think that he or she realized that his or her careless right turn nearly caused an accident. Was he or she shaken by the incident as I was? Did he or she reassess the actions that lead to it? Or is he or she going to tell his or her friends today about the “idiot cyclist” who nearly hit the car?

I am the lucky one here. It irks me to write those words. If there had been a crash, I would have been the one hurt, sprawled across the hood of a Prius, perhaps just road rash but possibly worse, the victim of just another unfortunate driver decision. We cyclists always lose, fault or not.

Of course, nothing will come of today’s event. I have no video, no witnesses, no tell-tale marks, no road rash, nothing — just a memory of a bad moment that somehow turned out OK. The driver and I each will be back on the road soon, anonymous users of the streets, fighting and clawing for space. Perhaps there is no lesson here. Perhaps there is nothing to say but that stuff happens. May such stuff never happen again.

A certain specious folly

July 17, 2013 1 comment

I’m not exactly sure where we are on the “Ghandi-meter” of change, but Syd Mead’s column on the “specious folly” of bicycle-as-transportation seems to be somewhere between the time when “they laugh at you” and when “they fight you.” The direct comments on the piece address most or all of the practical points he missed, which might be more simply stated that we cyclists have already solved his concerns. Can’t carry a watermelon? Done that. Can’t travel ten miles? Do that all the time. Bike lanes create traffic congestion? Traffic was congested before and getting worse. And so on.

It almost seems too convenient to point out that Mead, a so-called futurist, can’t conceive of a practical future for bicycles in an urban environment. This is even a little ironic. If one looks at the drawings he did in 1988 of Los Angeles in 2013, it’s pretty clear that his idea of the future was a bit different than what we’ve got. His streetscapes include “Metro Rail tubes,” but few sidewalks; futuristic cars, but hardly any traffic; hundreds of buildings, but not a single person in sight. One wonders whether somehow his future is so bleak that people don’t exist anymore, or don’t want to be outside anymore, or won’t enjoy the pleasure of a bike ride.

The column’s biggest flaw? Mead doesn’t provide alternatives. Bicycles go far towards a real solution to at least three problems we face in urban environments: traffic, pollution, and public health. It’s one thing to point out that most people won’t travel twenty miles on a bicycle, it’s another to propose an actual solution to congestion. If he hasn’t noticed, car trips on L.A.’s surface streets now travel at a bicycle pace, rarely exceeding an average of twenty miles-per-hour during business hours. Cars are polluting our environment, and it seems doubtful that his 1970s-era monster “land yacht” would help much. Americans are as fat as they’ve ever been, but somehow it doesn’t seem that anyone would lose weight riding around in one of his “Tron” Light cycles. It’s one thing to snipe at bicycles and their alleged limitations, it’s another to find better ways to replace them.

Maybe he should consider a vacation in the Netherlands. I hear they’re doing some amazing things with bicycles. Stuff that we might be trying to implement here.

Categories: Los Angeles, Planning