Crash Data Fallacies

LTRs know that I have been working with crash data for quite some time now.

I have gone from being confused about the cause of crashes to having a good idea on how crashes occur and back to being confused. I think confused is the right place to be.

To recap, there are only a few parameters which determine whether you will live or die in a bicycle crash.

First is speed, how fast you are going and how fast the cars are going. It you stay below twenty miles per hour, you’ll probably live. If you ride in areas where the average traffic speed is twenty five or below, you’ll probably live.

That’s it. All the other data is gibberish because it does not predict future crash survival.

Deadly collisions occur everywhere and they kill people regardless of skill, lane positioning, and helmets.

Part of the problem, I think is that this is NOT what people want to hear. They want to ride fast AND feel safe.

Because of this, we get the notions of Crash Data Analysis. The idea is to look at crash data in order to determine why and how the crash occurred so you can, hopefully, learn lessons that you can use to prevent yourself from getting into a crash.

On the face of it, this is a good idea. However, there are many problems with it. One of them is that the biggest proponants of this, routinely obsess over smaller dangers while ignoring larger ones.

For example, what’s more likely? A right hook or a left one? What happens more often collisions in the intersections or in the travel lane? What’s more likely to kill you, a dooring or a rear ending?

The answers to these questions depend on how you lump the data together as well as what sources you look at. You can make “edge riding” look more deadly by combing all kinds together, legal (bike lane) and illegal (sidewalk riding). Or you can make “taking the lane” seem safer by cutting the data into sub-catagories based on time and fashion choices while concealing the total.

If you look at the data from the point of view of deciding where and how to ride, you’ll find that you matter where you choose to ride, you can find people who died riding there. This does not make all cycling unsafe but it does tell us that there are limitations to crash data analysis.

Malcolm Gladwell is guilty of making a similar mistake. []

“Yet, like a golf tournament filled with the world’s greatest players, air travel is a marvelous display of perfection: airplanes manage to land millions of times every year with very few accidents.”

The same is true for cycling. Most cyclists, whether they ride on the sidewalk, with or without a helmet, inside or outside the door zone, on a path, on a track, on in the middle of the road do so safely.

If you think about all the dangers, the lack of cycling education, the “conflict points”, the negligent driving, the rapant law breaking (by motorists and cyclists), and the lack of focus (mostly by motorists, but not always), you will wonder how someone can ride a bicycle anywhere safely. But they do. More often than not. A LOT more often than not. And most of us don’t wear helmets, don’t take classes, and don’t like to ride next to high speed cars. But we’re still more likely than not to survive a given bicycle ride.

“Like the golf gallery surrounding an errant ball landed among the trees, we surround and gawk at every minute detail of the latest airplane crash. We run through all kinds of scenarios about what went wrong, and talk about them.”

“I am not an exception; watching a tournament, I also fixate on the golfers’ mistakes. When I see a golfer hitting a poor shot, I take a moment trying to recreate the swing in my mind, trying to see if I could identify what went wrong. I picture the golfer making his approach to the ball; the stance; the back swing; the alignment of the club head when the back swing reaches the top; the down swing; location of the hip during the down swing; the follow-through. Then I think about the path of the ball flight, and try to identify which part of the swing contributed to the deviation from the intended path.”

There is nothing wrong with doing this. But we are only doing so AFTER the fact. The worst part is that we assume that what they were doing: riding with ear phones, sidewalk riding, etc, contributed to the accident. But doing so ignores all those thousands of times when we do those things and we are safe. It also ignores all those times when people do things the so-called RIGHT way, and they still die. This happens far, far more often than people think. And all the safety organizations in the world, who teach behavior modification, can not save a single cyclist from a motorist who’s out of control. There’s no place on the road or even the sidewalk that will make you safe 100% of the time.

But there are ways to make the roads safer. These methods are tested, reliable, and ought to be implemented.


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