Collision Data, Displayed Geographically

Cyclist involved collisions in and around the Bike Kitchen in 2008
Cyclist involved collisions in and around the Bike Kitchen in 2008

Have you wished you knew how safe each street is for cycling?  Thanks to Deputy Chief David Doan, Mihai Peteu, Sergeant David Krumer, Paul Bringetto, Tait McCarthy, and Lyke Thompson, Bikeside is proud to bring the community one step closer to that goal.  Above we have displayed all the collision data from 2008 recorded by LAPD (involving cyclists.)  A single red dot represents a collision, and a larger red dot with a 2 or a 3 or a 4 in it represents 2 or 3 or 4 collisions.  As you can see, East Hollywood, the defacto center of bike culture in LA, has plenty of accidents.

As always, the problem is we don’t know how many cyclists ride these streets, so the data does not give relative risk.  Regardless, if you check out the maps for San Fernando Valley, Van Nuys Blvd stands out like a fresh bloodstain.

Collisions in the central Valley in 2008 involving cyclists (click to embiggen)
Collisions in the central Valley in 2008 involving cyclists (click to embiggen)

Where are we getting these maps and how can you view and play with them?  Check back next week!

Alex Thompson

Bikerowave co-founder, Cyclists' Bill of Rights co-author, President of Bikeside, and Math Phd. HULK SMASH straight from Michigan!

9 thoughts on “Collision Data, Displayed Geographically

  1. Unfortunately, localization isn’t a factor in bicycle fatalities. Bike accidents cluster around bicycle infrastructure because of the higher incidence of cyclists. The map demonstrates the locations of cyclists, many of whom get hit, but perhaps not the locations where cyclists are likely to get hit. Bike accidents occur like any other vehicular accidents: we don’t determine a driver’s risk according to where they live, but based on their driving record. Likewise, a collision between a cyclist and a driver is more the result of the parties involved than the locale.

  2. Dear Ele, A couple of responses:

    As far as I understood it, the map doesn’t demonstrate “the locations of cyclists, many of whom get hit” but instead demonstrates where the cyclists were actually hit.

    My insurance company adjusts my auto insurance liability rates according to my zip code. I’m fairly certain that this is standard practice: zip code affects everything from the junk mail you receive to your gas prices. Where you live matters as much as who you are.

    And without getting too overly theoretical, people get in accidents, but not necessarily in circumstances of their own choosing. If we see a cluster of accidents along a short stretch of Van Nuys (which we do), and if Van Nuys tends to have significant numbers of cars driving in excess of 35 mph (which is why the DoT has talked about raising the speed limits), we need to ask if there’s a relationship between the two (and I think that’s what Ubrayj was getting at).

    On a related note, I think it’s dangerous to see all accidents as a result of increased bicycle infrastructure (how much infrastructure is there on Van Nuys?). True, if you assume the rate of accidents are constant all over the city (which the map clearly demonstrates is NOT the case), it’s reasonable to expect that more cyclists will cause more accidents (because, it seems, cyclists are always at fault???). But if you look at any number of cities around the country, it’s clear that more infrastructure does NOT lead to more accidents. If anything, it decreases the incidence.

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